TEST BANK for Biology Life on Earth with Physiology. 11th Edition by Audesirk Gerald, Audesirk Teres by welldoneassistant

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Scientific inquiry is based on A) cultural biases or traditions. B) information found in a gossip magazine. C) natural causes. D) stories that are passed down through generations. Answer: C 2) Which of the following is an example of a natural cause? A) Mice arise from discarded garbage. B) Epilepsy is a disease caused by uncontrolled firing of nerve cells in the brain. C) Maggots appear spontaneously on rotting meat. D) If you sneeze, you will die. Answer: B 3) Science cannot answer certain faith-based questions because A) faith-based beliefs are impossible to either prove or disprove. B) there aren't enough variables. C) faith requires deductive reasoning. D) scientists are not able to study human behavior. Answer: A 4) Which of the following is FALSE about scientific theories? A) They can be either supported or modified by new observations. B) They are used to support observations using deductive reasoning. C) They are firmly established and cannot be refuted. D) They are developed by inductivereasoning. E) They have been thoroughly tested. Answer: C 5) Which of these would be an example of a NON-scientific study? A) NASA sends tadpoles up in the space shuttle to see how gravity affects their development. B) People are immunized with different vaccines to determine their relative effectiveness against the flu virus. C) A study determines differences in the species composition in two parks. D) Consumers are asked which tomato variety produces the best-tasting spaghetti sauce. E) A company uses different advertising methods for a product to determine which one produces the most sales. Answer: D 6) The scientific method includes all of the following EXCEPT A) an observation. B) a hypothesis. C) a testabletheory. D) experimentation. E) conclusions. Answer: C

7) We use the scientific method every day. Imagine that your car doesn't start one morning before school. Which of these is a reasonable hypothesis regarding the problem? A) If I put gas in my car, it will start. B) I should change the battery or the starter. C) I should add a quart of oil. D) I should check whether the lights were left on and drained the battery. E) I'm going to be late. Answer: A 8) A scientific theory A) is a general explanation for natural phenomena. B) is less reliable than ahypothesis. C) will never be changed. D) is an educated guess. Answer: A 9) A scientific explanation that is conditional and requires more investigation is called a(n) A) fact. B) hypothesis. C) control. D) observation. E) theory. Answer: B 10) A carefully formulated scientific explanation that is based on extensive observations and is in accord with scientific principles is called a A) postulate. B) theory. C) hypothesis. D) control. E) fact. Answer: B 11) All of the following are features of the scientific method EXCEPT A) repeatable by other scientists. B) deductive reasoning. C) observation and experimentation. D) hypothesis formulation. E) supernatural causes. Answer: E 12) Suppose you are testing a treatment for AIDS patients and find that 75% respond well, whereas 25% show no improvement or a decline in health. You should A) begin work on developing a new drug. B) review the results, modify the drug or the dosage, and repeat the experiment. C) conclude that only 75% of AIDS patients should be treated. D) discontinue experimentation with this treatment because 25% of patients did not improve. E) conclude that you have proven the effectiveness of the drug. Answer: B

13) Alexander Fleming observed a colony of mold that inhibited the growth of nearby bacteria. What was the hypothesis proposed by Fleming to explain this result? A) The bacteria changed their DNA when growing near the mold. B) The mold produced a substance that killed nearby bacteria. C) The mold used all of the nutrients so that the bacteria couldn't grow. D) The mold was dead. Answer: B 14) Imagine that 1 milliliter of an experimental drug diluted in a saline solution is injected into 20 pregnant mice to determine possible side effects. Which of the following is a suitable control for this experiment? A) 20 pregnant mice injected with 1 milliliter ofsaline B) 20 pregnant mice injected with 2 milliliters of thedrug C) 20 non-pregnant mice injected with 1 milliliter of the drug D) 20 male mice injected with 1 milliliter of thedrug E) 20 male mice injected with 1 milliliter of saline Answer: A 15) Which of the following statements is a hypothesis rather than a theory? A) Modern organisms descended from preexisting life-forms. B) Female birds prefer to mate with male birds that have longer tails. C) Matter is composed of atoms. D) Living things are made of cells. Answer: B 16) Which of the following is TRUE regarding faith-basedbeliefs and scientific theories? A) Faith-based beliefs can become scientific theories. B) Both faith-based beliefs and scientific theories can be proven. C) Scientific theories are not modifiable, but faith-based beliefs are. D) Any and all scientific theories can be disproven, but faith-based beliefs cannot. E) Any and all faith-based beliefs can be disproven, but scientific theories cannot. Answer: D 17) Which is the correct sequence of increasing organization? A) Cell, tissue, organ, organ system B) Organ, tissue, cell, molecule C) Organelle, tissue, cell, organ D) Molecule, cell, organelle, organ E) Atom, molecule, tissue, cell Answer: A 18) Which of the following levels of organization is the most inclusive (i.e., includes the most life-forms)? A) Community B) Species C) Biosphere D) Ecosystem E) Population Answer: C

19) The smallest units that still retain the characteristics of an element are called A) atoms. B) tissues. C) organic molecules. D) cells. E) molecules. Answer: A 20) Which of the following is an example of deductive reasoning? A) If an object exhibits all the characteristics of life, it must be living. B) All objects on Earth will fall down when dropped, and none will "fall up." C) Living objects are composed of cells. D) Atoms make up molecules, which make up cells, which make up tissues. Answer: A 21) The experiments of Francesco Redi A) disproved that maggots and flies were related. B) used the scientific method to prove the idea of spontaneous generation. C) determined that fly larvae were present in raw meat, and when left on the counter they turned into flies. D) disproved the idea of spontaneous generation. E) disproved the scientific method. Answer: D 22) Francesco Redi designed an experiment to test the notion of spontaneous generation. He left the first jar of meat open to the air and covered the second jar. The first jar would be called the jar. A) hypothetical B) control C) conclusive D) experimental Answer: B 23) To test the effect of vitamin D on growth, two groups of rats were raised under identical conditions and fed the same diet. One of the groups received daily injections of vitamin D. The other group received injections of saline, which did not contain vitamin D. All the rats were weighed weekly for 2 months. In this experiment, the control was the A) group receiving saline. B) average weight gain of therats. C) 2-month period of time. D) group receiving vitamin D. Answer: A 24) Evolution is sometimes described as the change from preexisting life-forms to modern-day organisms. What actually changes, in every case of evolution, is the A) species' physical appearance. B) rate of reproduction. C) ability of organisms to respond to external stimuli. D) genetic makeup of the species, due to mutations. E) energy and nutritional demands of the organism. Answer: D

25) All of the following are important to the theory of evolution EXCEPT A) variation in traits within an entire population. B) mutations. C) inheritance of traits. D) changes in individuals within theirlifetimes. E) environmental change. Answer: D 26) Which is NOT an example of evolution? A) Flightless birds living on islands without predators B) The development of antibiotic-resistantbacteria C) A dog learning how to open the cabinet where its food is kept D) Annual changes in the flu virus due to mutations E) The 2- to 3-year effectiveness of most commercial pesticides in killing insects Answer: C 27) A mutation can be the cause for A) environmental change. B) growth and development. C) sexual reproduction. D) natural selection. E) sperm and egg formation. Answer: D 28) A mutation is a A) physical deformity, such as the loss of a limb. B) defective egg or sperm cell. C) dose of radiation. D) change in the DNA sequence. Answer: D 29) In a word, "evolution" means A) change. B) selection. C) improvement. D) nature. Answer: A 30) The concept of evolution is based on A) all genetic variation in a population being equally successful in the same environment. B) any type of genetic variation within a population. C) survival and successful reproduction in organisms with favorable variations. D) parents with variations that pass these variations on to their offspring. Answer: C

31) All of the following are examples of adaptations EXCEPT A) insects that resemble twigs. B) larger teeth in beavers for gnawing wood. C) flower coloration that attracts pollinators. D) mice learning a maze to get food. E) different beak shapes for birds that eat seeds or insects. Answer: D 32) Suppose an organism has an enzyme that repairs changes in its DNA. The result is a decrease in mutations. This trait would definitely influence the organism's ability to A) evolve. B) maintain homeostasis. C) move. D) obtain energy. Answer: A 33) The variation among individuals, on which natural selection acts, describes A) random occurrences in the lifetimes of individuals. B) genetic differences. C) physical training and exercise. D) nutritional differences. Answer: B 34) Chromosomes are made of A) proteins. B) cells. C) DNA. D) carbohydrates. E) DNA and proteins. Answer: E 35) A change in the genetic makeup of a species over time is called A) evolution. B) natural causality. C) adaptation. D) mutation. Answer: A 36) Adaptations include all of the following EXCEPT A) reduced heart rate and oxygen consumption in seals that dive deep for long periods of time. B) inborn migratory behavior of young birds born in the Arctic. C) larger body size in male gorillas, which fight over females. D) teaching a pet parrot totalk. Answer: D 37) Dinosaurs are not alive today because they A) evolved adaptations that were beneficial in their constant, unchanging environment. B) did not evolve fast enough to keep up with rapid environmental change. C) did not possess the genetic material that beneficial mutations act on. D) evolved too quickly in response to a changing environment. Answer: B 6

38) Which of the following is a characteristic of living organisms? A) Eat other organisms B) Have membrane-bound organelles C) Have a nucleus D) Maintenance and regulation of internal conditions E) Ability to produceenergy Answer: D 39) All of the following are true of all living organisms EXCEPT that they A) possess either DNA or RNA. B) respond to stimuli. C) are made of cells. D) can grow. E) can reproduce themselves. Answer: A 40) After you drink a glass of acidic lemonade, your body's pH does not change. This is an example of how humans and other organisms A) maintain cellular organization. B) are immune to weak acids. C) maintain precise internal conditions through homeostasis. D) evolve in response to the environment. Answer: C 41) Why do humans born without sweat glands usually not survive? A) Sweating is an important mechanism for maintaining the correct body temperature. B) Sweating is the only way the body eliminates excess water. C) Sweat glands create openings in the skin where gas exchange occurs. D) Sweating is important for eliminating impurities from the body. Answer: A 42) An organism's ability to detect stimuli from either the internal or external environment is called A) mutation. B) DNA. C) evolution. D) natural selection. E) responsiveness. Answer: E 43) You observe a plant on your windowsill that is growing at an angle toward the outside. This is an example of a living thing A) responding to stimuli. B) evolving. C) reproducing. D) maintaining precise internal conditions. Answer: A

44) Using its antennae, the male moth finds female moths by following a trail of airborne chemicals, called pheromones, upwind from the female producing them. This is an example of how living things A) grow. B) detect and respond to stimuli. C) acquire nutrients. D) reproduce. E) maintain precise internal conditions. Answer: B 45) An organism in the domain Eukarya is characterized by all of the following EXCEPT A) being composed of prokaryotic cells. B) the ability to maintain precise internal conditions. C) ingestion of organic matter to acquire nutrients. D) the potential to grow and reproduce. Answer: A 46) Why do heterotrophs require "food" for survival? A) Food provides at least half of the water required by heterotrophs. B) Heterotrophs cannot photosynthesize without the chemicals provided by food. C) Food provides the organic chemicals needed by heterotrophs. D) Food is an alternative source of energy for heterotrophs when sunlight is unavailable. Answer: C 47) The main difference between an autotroph and a heterotroph is A) how they respond to stimuli. B) how they obtain energy. C) how they reproduce. D) their ability tomove. Answer: B

MATCHING. Choose the item in column 2 that best matches each item in column 1. For the following question(s), choose the characteristic of a living organism that best corresponds to each statement. Selections may be used once, more than once, or not at all. 48) A sunflower follows the sun as it moves across the sky during the period of a singleday.

A) Response to stimuli B) Growth

Answer: A C) Evolution 49) A puppy is born weighing 5 pounds and eventually becomes a 75-pound golden retriever.

D) Reproduction

Answer: B 50) At the beginning of the week, a plant is 3 inches tall and at the end of the week, it is 4 inches tall. Answer: B 51) A paramecium moves from direct light toward the dark. Answer: A 52) A bacterium divides into two bacteria that are identical to, but smaller than, the original bacterium. Answer: D 53) Over time, the average neck length of giraffes has increased. Only those giraffes with longer necks survived by eating the leaves high up on the trees, and they were able to reproduce and pass those long-neck genes on to the next generation. Answer: C MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 54) Of the following levels of organization, Archaea have A) molecules only. B) organs only. C) atoms only. D) atoms, molecules, and organs. E) atoms and molecules. Answer: E

55) In evolutionary terms, which of the following cells is considered to be the most primitive? A) Prokaryote B) Eukaryote C) Autotroph D) Heterotroph Answer: A 56) In which kingdom does a multicellular, eukaryotic, photosynthetic organism belong? A) Fungi B) Protists C) Plantae D) Animalia Answer: C 57) A basic difference between a prokaryotic cell and a eukaryotic cell is that the prokaryotic cell A) is considerably larger. B) possesses membrane-bound organelles. C) lacks a nucleus. D) is structurally more complex. E) lacks DNA. Answer: C 58) Which of the following statements about the Bacteria and Eukarya domains is TRUE? A) All members of Bacteria are prokaryotic cells and all members of Eukarya are eukaryotic cells. B) Only members of Eukarya have the ability to grow and reproduce. C) All members of Bacteria are single-celled and all members of Eukarya are multicellular. D) All members of Bacteria acquire nutrients via ingestion and all members of Eukarya acquire nutrients by photosynthesis. Answer: A 59) Which group has prokaryotic individuals? A) Domain Archaea B) Kingdom Fungi C) Kingdom Plantae D) Kingdom Animalia E) Protist kingdoms Answer: A 60) Which kingdom possesses unicellular animal-like species and unicellular plantlike species? A) Fungi B) Plantae C) Protista D) Animalia Answer: C 61) A cell that lacks organelles is a(n) A) animal cell. B) prokaryotic cell. C) eukaryotic cell. D) member of the Kingdom Plantae. Answer: B 10

62) Scientific theories are the same in any part of the world (meaning they do not vary by location). A) True B) False Answer: B 63) Scientific experimentation generally leads to more questions. A) True B) False Answer: A 64) A good experiment should include as many variables as possible at the same time. A) True B) False Answer: B 65) A hypothesis is typically stated as an "If . . . then" statement. A) True B) False Answer: B 66) Variation among organisms is due to mutations. A) True B) False Answer: A 67) Adaptations aid in the survival and reproduction of an organism in a particular environment. A) True B) False Answer: A 68) The energy that sustains life ultimately comes from sunlight. A) True B) False Answer: A 69) Photosynthetic bacteria are examples of autotrophs. A) True B) False Answer: A 70) Prokaryotic cells have a true nucleus and eukaryotic cells do not. A) True B) False Answer: B 71) Biodiversity is the total number of organisms in an ecosystem. A) True B) False Answer: B

SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 72) All scientific study begins with

and the formation of testable hypotheses.

Answer: observations 73) A group of individuals who are able to interbreed, regardless of their geographical location, is defined as a(n) . Answer: species 74) A group of similar, interbreeding individuals that live in the same area is a(n)

Answer: population 75) The basic unit of life is the

Answer: cell 76) Errors or changes in the DNA of an organism are called

Answer: mutations 77) The three natural processes that underlie evolution are genetic variation, inheritance, and

Answer: naturalselection 78) Single-celled organisms that lack a nucleus belong to the domains Bacteria and

Answer: Archaea 79) Cells that contain a nucleus are eukaryotic, and cells without a nucleus are

Answer: prokaryotic 80) Photosynthetic plants are considered "self-feeders," or

Answer: autotrophs 81) Consider the observation that people taking Drug X for headaches also seem to have low blood pressure. Design a simple experiment based on this observation, and include a hypothesis statement and your actual experimental design for the study. Answer: Answers should include a controlled variable, repetition, and a hypothesis statement. 82) The instructions for producing and maintaining life are contained in what molecule? Answer: DNA 83) Evolution is based on adaptations that aid in the survival and reproduction of a species. List three different adaptations. Answer: There are many correct answers. Some acceptable answers are roots of plants that help land plants gain water, fleshy fish fins that allow for movement across a surface, and wings of eagles that aid in hunting. 84) Imagine that in 2020 you are the top biologist at a research station studying biodiversity in Costa Rica. A young scientist brings you a sample from a previously unexplored site. She asks you to look at the sample and determine whether it indeed contains microscopic, living organisms. As you begin your investigations, you must first decide what characteristics distinguish life from nonlife. How would you differentiate a living organism from nonliving matter (including viruses and prions)? Answer: Answers should describe several characteristics of a living organism.

85) Define biodiversity. Answer: Biodiversity is the number of species in a given geographic region. 86) List four characteristics of living things, and give an example to illustrate each. Answer: There are many correct answers. Some acceptable answers are: Living things are both complex and organized (cells have organelles with specific organization); living things respond to stimuli (plants grow toward light); living things maintain homeostasis (the human body maintains its body temperature); living things acquire and use energy (plants use photosynthesis); living things grow (animals grow during their lifetime); living things reproduce (organisms produce offspring); living things have the capacity to evolve (bacteria have evolved antibiotic resistance). 87) Describe at least two cellular-level differences between a photosynthetic prokaryote and a plant. Answer: The prokaryote does not have any membrane-bound organelles (including a nucleus), but the plant (being a eukaryote) does. The prokaryote is unicellular, whereas the plant is multicellular. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 88) Which of the following is NOT a part of the community shown in this figure?

A) Pronghorn antelope B) Snake C) Hawk D) Stream E) Grass Answer: D

89) The "first cells" shown at the bottom of this illustration were most likely

A) fungi. B) protists. C) prokaryotes. D) animals. E) plants. Answer: C 90) A 57-year-old woman was admitted to a hospital with an infected toe, and the infection was spreading rapidly. The damage was being caused by an unknown microorganism that could not be cultured in the lab. Doctors observed that antibiotics, which kill only prokaryotes, were ineffective. They suspected that the microbe was a fungus, so they tried the drug Amphotericin, which targets the ergosterols in fungal cells. Because animal cells contain cholesterols, not ergosterols, they are unaffected by the drug. Shortly after receiving Amphotericin, the patient improved, her infection ceased, and she was released from the hospital. In this scenario, what was the hypothesis? A) Antibiotics will not kill the microbe because it is a fungal species. B) If the infection is caused by an animal, then Amphotericin will cure the patient. C) A microbe that has cholesterol is causing the infection. D) The infection will spread rapidly. E) Why didn't the antibiotics kill the microbe that caused the infection? Answer: A 91) Suppose that a meteorite crashes into Earth and a sample of it is taken to a local research lab for analysis. Embedded several inches within the rocky structure, a microscopic cluster of dormant, spore-like structures is found. The scientists culture some of this material in a standard microbiological nutrient broth, and they are surprised to find many single-celled "organisms" moving around, growing, and reproducing in the broth. The "organisms" behave the same in both daylight and dark conditions, do not require oxygen, and thrive under a wide range of temperatures and pH levels. They stop moving, growing, and reproducing, however, when fewer nutrients are available in themedium. In this scenario, the "organisms" most closely resemble a(n) A) heterotrophic species of Archaea. B) heterotrophic species of Eukarya. C) photosynthetic species of Bacteria. D) nonliving virus. E) autotrophic species of Eukarya. Answer: A

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) A substance with specific properties that cannot be broken down or converted into another substance is called a(n) A) molecule. B) compound. C) mixture. D) ion. E) element. Answer: E 2) If you examined the human body on a chemical composition basis, which of the following combinations of elements would be most common? A) O, C, H, N B) O, C, N, Na C) C, H, Ca, Cl D) C, N, Ca, S E) O, C, P, S Answer: A 3) The atomic number of an atom is defined as the A) total number of electrons andneutrons. B) total number of energy shells. C) number of protons in the atomic nucleus. D) number of neutrons in the atomic nucleus. E) number of electrons in the outermost energy level. Answer: C 4) Phosphorus has an atomic number of 15, so what is the distribution of its electrons? A) The first, second, and third energy levels have 5 electrons each. B) The first energy level has 8 and the second has 7. C) The first energy level has 2, the second has 8, and the third has 5. D) The first energy level has 2 and the second has 13. E) The electron arrangement cannot be determined from the atomic number alone. Answer: C 5) Which four elements make up approximately 96% of living matter? A) Carbon, hydrogen, nitrogen, oxygen B) Carbon, oxygen, calcium, sulfur C) Carbon, sodium, chlorine, magnesium D) Carbon, phosphorus, hydrogen, sulfur E) Oxygen, hydrogen, calcium, sodium Answer: A 6) Imagine that you have been hired as a chemist and your first task is to examine a newly discovered atom. The paperwork you are given states that its atomic number is 110. What does this mean? A) The atom contains 55 protons and 55 neutrons. B) The atom contains 55 electrons. C) The atom is an isotope. D) The atom contains 110 protons. Answer: D

7) Iron is an important element in human body cells. If iron has an atomic number of 26, what does this tell you about this element? A) An iron atom has 26 protons. B) An iron atom is unable to become an isotope. C) An iron atom has 13 electrons and 13 protons. D) An iron atom has 13 protons and 13 neutrons. Answer: A 8) Carbon-14 is often used for carbon dating, where scientists measure the rate of carbon-14 decay to determine the age of items. Carbon-14 contains six protons and eight neutrons. During the process of carbon-14 decay, one of its eight neutrons becomes a proton and an electron is emitted. Which of the following is the best explanation of what has occurred? A) The resulting atom is still carbon-14. B) The resulting atom has a more stable nucleus. C) An ionic bond has formed. D) The resulting atom is now a different element because the number of protons has changed. Answer: D 9) Radioactive isotopes are biological tools that are often used to A) detect brain tumors and other important medical technologies. B) build up a store of calcium in a cell. C) increase the pH of blood. D) measure the size of fossils. Answer: A 10) For an atom to achieve maximum stability and become chemically inert, what must occur? A) Ionization occurs. B) Its outermost energy shell must be completely filled with electrons. C) Electron pairs are shared. D) The number of electrons must equal the number of protons. Answer: B 11) An atom's nucleus is composed of A) neutrons and electrons. B) protons only. C) protons and electrons. D) protonsandneutrons. E) neutrons only. Answer: D 12) The formation of ions involves the A) sharing of protons. B) gain or loss of protons. C) sharing of electrons. D) gain or loss of neutrons. E) gain or loss of electrons. Answer: E

13) If a certain atom has a tendency to lose two electrons, that atom can then become a(n) A) polar molecule. B) ion. C) isotope. D) water molecule. Answer: B 14) The formation of sodium chloride (NaCl) is the result of A) attraction between opposite charges. B) chemical unreactivity. C) covalent bonding. D) repelling between the same charges. Answer: A 15) Atoms or molecules that have gained or lost electrons are called A) bases. B) ions. C) acids. D) buffers. E) covalent. Answer: B 16) Most biological molecules are joinedby A) ionic bonds. B) peptide bonds. C) covalent bonds. D) hydrogen bonds. E) disulfide bonds. Answer: C 17) Sulfur is an essential element in the human body, and studying its characteristics is important in understanding human physiology. Sulfur atoms have six electrons in their outer shell. Based on this information, which of the following is TRUE? A) Sulfur has eight electrons in its outer shell. B) Sulfur is inert. C) Sulfur is an important isotope of hydrogen. D) Sulfur can form important molecules using covalent bonds. Answer: D 18) Free radicals contain unpaired electrons in their outermost energy shell, so they react readily with other atoms or molecules to reach a more stable state. Which of the following could potentially be a free radical? A) Helium (atomic number 2) B) Magnesium (atomic number 12) C) Neon (atomic number 10) D) Fluorine (atomic number 9) Answer: D

19) Free radicals are considered dangerous because they A) emit dangerous radiation. B) damage oxygen and cause it to become an antioxidant. C) steal electrons from other atoms, causing those atoms to become unstable. D) attack the atomicnucleus. Answer: C 20) Scientists recommend a diet rich in antioxidants to stay healthy. What occurs at the atomic level to explain this recommendation? A) Antioxidants cause an increase in pH, which is necessary for neutrality in cells. B) Antioxidants are inert and do not interact with free radicals. C) Antioxidants prevent free radicals from attacking other atoms or molecules. D) Antioxidants steal electrons, which gives cells extra energy. Answer: C 21) Which of the following best explains why a particular atom may not form compounds easily? A) The atom has seven electrons in its outer shell. B) The atom has no electrons. C) The atom has an uneven number of protons. D) The atom's outer energy shells are completely full. Answer: D 22) The element carbon has atomic number 6. Carbon most likely A) forms ionic bonds with otheratoms. B) forms four covalent bonds. C) donates two electrons to anotheratom. D) shares two electrons with another atom. Answer: B 23) Sodium (Na), atomic number 11, has a tendency to lose an electron in the presence of chlorine. After losing the electron, Na has protons in its nucleus. A) 11 B) 10 C) 12 D) 21 E) 22 Answer: A 24) Carbon has atomic number 6. Carbon most likely A) shares protons. B) loses protons. C) loses electrons. D) shares neutrons. E) shares electrons. Answer: E

25) What does H-O-H represent? A) Mixture including water B) Molecule of water C) Atom of water D) Ionic bonding of water Answer: B 26) The atomic number of hydrogen is 1. Based on this fact, all of the following must be true of hydrogen gas (H2) EXCEPT that it A) uses covalent bonds to form the molecule. B) is a stable molecule. C) isa polar molecule. D) shares one pair of electrons between the two hydrogen atoms. Answer: C 27) Polar covalent bonds form when A) an acid and a base are combined. B) electrons are sharedunequally between atoms. C) atoms from two molecules are repelling each other. D) more than one pair of electrons is shared. E) ions are formed. Answer: B 28) Which of the following represents a molecule characterized by polar covalent bonding? A) H2 B) H2O C) O2 D) CH4 E) NaCl Answer: B 29) What type of bond is easily disrupted in aqueous solutions (one in which the solvent is water)? A) Covalent B) Ionic C) Polar covalent Answer: B 30) If sulfur has an atomic number of 16, how many covalent bonds can it form with other atoms? A) Eight B) Four C) Zero D) Two E) Six Answer: D

31) The part of the atom that has the greatest biological interest and interactions with other atoms is the A) innermost electron shell. B) neutron. C) proton. D) electron. Answer: D 32) Which of the following pairs has the most similar chemical properties to each other? A) 1H and 2He B) 12C and28Si C) 12C and 14C D) 16O and 32S E) 1H and 22Na Answer: C 33) A single covalent chemical bond represents the sharing of how many electrons? A) Three B) Two C) One D) Four E) Six Answer: B 34) Polar molecules A) have an overall positive electric charge. B) have an overall negative electric charge. C) are always ions. D) have an unequal distribution of electric charge. E) have an equal distribution of electric charge. Answer: D 35) The hydrogen bond between two water molecules forms because water is A) a large molecule. B) polar. C) nonpolar. D) hydrophobic. E) a small molecule. Answer: B 36) Hydrogen bonding can take place between a hydrogen atom and what other atom? A) Hydrogen B) Oxygen C) Nitrogen D) Nitrogen, oxygen, and fluorine E) Fluorine Answer: B

37) Which statement is an accurate description of water molecules? A) They are uncharged and nonpolar. B) They are slightly charged andpolar. C) They are ionically bonded. D) They are charged and nonpolar. Answer: B 38) Which of the following is an example of hydrogen bonding? A) The bond between the H of a water molecule and H of a hydrogen molecule B) The bond between H of one water molecule and H of a separate water molecule C) The bond between O of one water molecule and H of a separate water molecule D) The bond between O and H in a single molecule of water E) The bond between O of one water molecule and O of a separate water molecule Answer: C 39) Which of the following results from a transfer of electron(s) between atoms (e.g., NaCl)? A) Nonpolar covalent bond B) Polar covalent bond C) Ionic bond D) Hydrogen bond E) Electron-proton interaction Answer: C 40) Which of the following results from an unequal sharing of electrons between atoms? A) Nonpolar covalent bond B) Polar covalent bond C) Ionic bond D) Hydrogen bond E) Electron-proton interaction Answer: B 41) Which of the following best explains the attraction of water molecules to each other? A) Nonpolar covalent bond B) Polar covalent bond C) Ionic bond D) Hydrogen bond E) Electron-proton interaction Answer: D 42) Which of the following is LEAST affected by the presence of water? A) Nonpolar covalent bond B) Polar covalent bond C) Ionic bond D) Hydrogen bond E) Electron-proton interaction Answer: A

43) What happens when hydrochloric acid (HCl) dissociates in pure water? A) The concentration of OH- ions increases. B) The HCl molecules separate into H+ and Cl- ions. C) The pH of the solutionincreases. D) The water has a decrease of H+ ions. E) The HCl molecules float on top of the water. Answer: B 44) An atom of nitrogen attracts electrons more strongly than an atom of hydrogen. In an ammonia molecule (NH3), which of the following best describes the electrical charge of the individual atoms? A) The nitrogen is slightly positive. B) The nitrogen is slightly morenegative. C) The nitrogen becomes neutral. D) The hydrogens are strongly negative. E) Charges balance out and none of the atoms has any charge. Answer: B 45) If a substance measures 7 on the pH scale, that substance A) has equal concentrations of H+ and OH- ions. B) has a higher concentration of OH- than H+ ions. C) may be lemon juice. D) probably lacks OH- ions. E) is basic. Answer: A 46) A neutral solution A) has equal amounts of H+and OH-. B) has no H+. C) is hydrophobic. D) has a pH of 0. E) has no OH-. Answer: A 47) How do buffers work? A) They soak up extra acid and base. B) They monitor the blood pH. C) They accept and release H+. D) They accept and release OH-. E) They convert H+ and OH-to water. Answer: C 48) The human body must maintain a constant pH. In the blood, bicarbonate serves as a(n) maintain the necessary pH. A) buffer B) base C) acid D) solvent Answer: A

to help

49) Milk of magnesia is often used to treat stomach upset. It has a pH of 10. Based on this information, milk of magnesia A) is an acid. B) is a base. C) has the same pH as stomach acid. D) is hydrophobic. Answer: B 50) What is meant by the statement that water has a high specific heat? A) It grows hot quickly. B) The boiling point of water is low. C) It can absorb a lot of energy without changing temperature. D) Water can heat up to only a certain temperature. E) Water freezes easily. Answer: C 51) Which of the following properties of water enable(s) it to function as a regulator of temperature for living organisms? (Hint: Think about what happens when you are sunbathing.) A) High specific heat B) High specific heat and high heat of vaporization C) Low specific heat D) High specific heat and low heat of vaporization E) High heat of vaporization Answer: D 52) The fact that salt dissolves in water is best explained by the A) hydrophobic nature of salt. B) ionic nature of water molecules. C) hydrophobic nature of the water. D) slightly charged nature of water molecules. E) polar nature of water molecules. Answer: E 53) Hydrophilic molecules A) readily dissolve in water. B) do not readily dissolve inwater. C) are repelled by water. D) form hydrogen bonds among themselves. E) are neutral and nonpolar. Answer: A 54) Water moves through a plant because of the property of A) high heat of vaporization. B) high heat of fusion. C) cohesion. D) high specific heat. Answer: C

55) Water molecules are cohesive becausethey A) are repelled by nonpolar molecules. B) contain protons. C) form hydrogen bonds. D) make up 60% to 90% of an organism's body weight. E) stick to other polar molecules. Answer: C 56) When the acidic level of human blood increases, how is the proper balance of hydrogen ions (H+) restored? A) H+ ion-donor levels increase. B) Carbonic acid eats up the extra OH- ions. C) Bicarbonate (HCO3-) accepts H+ ions and forms carbonic acid. D) Bicarbonate (HCO3-) releases H+ ions that combine with excess OH- ions to form H2O. Answer: C 57) For ice to melt, it has to A) become less dense. B) increase its heat ofvaporization. C) increase its property of cohesion. D) absorb heat from its surroundings. Answer: D 58) What determines the cohesiveness of water molecules? A) Ionic bonds B) Hydrophobic interactions C) Covalent bonds D) Hydrogen bonds Answer: D 59) If you place a paper towel in a dish of water, the water will A) move up the towel because water molecules move quickly as it vaporizes. B) dissolve the towel because water is a good solvent. C) move up the towel as the water adheres to the paper towel while the cohesive water molecules stay bound to each other. D) separate into H+ and OH- ions, which will react with the paper towel molecules. E) move away from the towel because water molecules have hydrophobic interactions. Answer: C 60) Sweating is a useful cooling mechanism for humans because water A) can exist in two states at temperatures common on Earth. B) is an outstanding solvent. C) takes up a great deal of heat in changing from its solid state to its liquid state. D) ionizes readily. E) takes up a great deal of heat in changing from its liquid state to its gaseous state. Answer: E

61) In general, a substance that carries an electric charge can dissolve in water. Given this fact, which of the following would most likely NOT dissolve in water? A) Nonpolar molecules B) Polar covalent molecules C) Ionic compounds D) NaCl Answer: A 62) If you place a feather on the surface of a bowl of water, the feather remains suspended on the surface due to the A) surface tension of the water. B) polarity of the water. C) density of the water. D) fact that water is a good solvent. Answer: A 63) The specific heat of water is 10 times greater than that of iron. You place a metal pot full of water on the stove to heat it up. You touch the metal handle of the pot when the water is still only lukewarm. Which of the following best describes what happens? A) You burn your finger and pull your hand away from the hot metal handle. B) You find that the handle is cooler than the water in the pot. C) You find that both the water and the handle are the same temperature. D) You determine that metal pots full of water produce acids and bases. Answer: A 64) You drop a handful of common table salt into a glass of water. Which of the following best describes what is happening inside the glass at the molecular level? A) Water and sodium form a covalent bond. B) Sodium and chloride ions form a covalent bond. C) The positively charged hydrogen ends of the water molecules are attracted to sodium ions. D) The positively charged hydrogen ends of the water molecules are attracted to chloride ions. Answer: D 65) Your friend does a belly flop into a swimming pool. The stinging pain he feels is most likely due to the A) hydrophobic nature of your friend's skin. B) fact that water is a good solvent. C) surface tension of water (caused by the large number of hydrogen bonds that form between water molecules). D) pH of the water. Answer: C 66) Which of the following is the densest? A) Steam B) Liquid water C) Ice Answer: B

67) Unlike a rock, a reptile can sit in the hot sunshine without its body temperature soaring quickly. This is because the water in its body A) has a low specific heat. B) is a good solvent. C) has a high specific heat. D) is a poor solvent. Answer: C 68) Isotopes are atoms of the same element that have different numbers of protons. A) True B) False Answer: B 69) Every atom of the same element has an equal number of electrons and protons. A) True B) False Answer: A 70) Acids have pH values below 7, whereas bases have pH values above 7. A) True B) False Answer: A 71) The attractive force that holds two or more water molecules together is an example of an ionic bond. A) True B) False Answer: B 72) When water freezes, stable hydrogen bonds form between the water molecules that create an open, six-sided (hexagonal) arrangement. A) True B) False Answer: A 73) Water surface tension is a result of the cohesive nature of water molecules. A) True B) False Answer: A 74) To maintain a constant pH, buffers act to either accept or release H+. A) True B) False Answer: A 75) Most liquids become less dense upon solidification, but water is different in that it becomes denser when it solidifies. A) True B) False Answer: B

SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 76) The chemical properties of an element are determined by the number of

in its outermost energy shell.

Answer: electrons 77) Isotopes are atoms of the same element that have different numbers of

Answer: neutrons 78) The second electron shell is considered to be full when it contains

electrons.

Answer: eight 79) A basilisk lizard can run across the surface of a pond due to a property of water called

Answer: surfacetension 80) Ions and polar molecules that are electrically attracted to water molecules are

Answer: hydrophilic 81) What is the difference between covalent and ionic bonds? Answer: Covalent bonds are the sharing of electrons between atoms, whereas ionic bonds are the electric charge attraction between two ions (typically a metal and a non-metal). 82) more stable than a hydrogen atom (atomic number 1)? Answer: Two electrons completely fill the outermost electron shell of helium, but hydrogen must accept an electron before its outermost shell is filled. 83) What type of bonding exists between the slight positive charge of a hydrogen atom and the slight negative charge of a nearby oxygenatom? Answer: hydrogen bonding 84) What property of water, in which water molecules stick to each other, is responsible for the ability of plants to get water from their roots up to their leaves? Answer: cohesion 85) How does a base differ from an acid? Answer: A base is a solution with a concentration of OH- that is higher than the concentration of H+ (pH greater than 7). An acid has a H+ concentration that exceeds its OH- concentration (pH less than 7). 86) Imagine that you are trying to make a homemade salad dressing and place several drops of olive oil into a container of water. You stir the solution, but the oil doesn't readily mix. Instead, you observe a glistening clump of oil floating on the surface. Explain what is happening at the molecular level. (Your answer should include the term hydrophobic.) Answer: When oil molecules are together in water, their nonpolar surfaces are hydrophobic and nestle together. They are surrounded by water molecules that form hydrogen bonds with one another but not with the oil.

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 87) Which of these atoms would become inert if it accepted three electrons?

A) Carbon B) Phosphorus C) Oxygen D) Calcium Answer: B 88) Which of the following is attracted to the hydrogen "end" of a water molecule, as depicted in this figure?

A) ClB) NaCl C) H D) Na+ Answer: A

89) Different types of living matter often have different forms of the same elements in their bodies. For example, the nitrogen in an animal often has a slightly different atomic structure than the nitrogen in a plant. Recently, nutritionists have discovered how to deduce the diets of various animal species by examining the type of nitrogen (and other elements) inside their bodies. What is the chemical basis behind this scenario? A) Antioxidants buffer the potential damage that free radicals do to cells. B) Covalent bonds result when two atoms share electrons. C) Radioactive elements can be used to trace the paths of molecules through the body. D) Isotopes of the same element have the same atomic number but different atomic masses. E) Hydrophobic interactions keep water molecules from forming bonds with fats and oils. Answer: D 90) All animals need oxygen gas (O2) for their primary cellular-level functioning. Inside the cell, O2 is split apart into oxygen atoms. Eventually, electrons that are flowing through the cell will be "received" by this oxygen. But first, the electrons combine with protons present in the cell to form a basic element that has a single proton and a single electron. Then this element combines with the oxygen to form a certain chemical compound. In this scenario, what chemical compound is produced when this element combines with oxygen? A) Water (H2O) B) Bicarbonate (HCO3) C) Carbon dioxide (CO2) D) Ozone (O3) Answer: A

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Prions are known to cause A) sickle cell anemia. B) herpes. C) mad cow disease. D) the common cold. Answer: C 2) Which of the following is NOT an organicmolecule? A) Protein B) Carbon monoxide C) Monosaccharide D) Lipid E) Nucleic acid Answer: B 3) You are telling your friend that organic molecules are all made up of carbon backbones with hydrogens. She doesn't understand how there can be so many different organic molecules if they all are made up of the same basic components. You explain that organic molecules A) vary because they possess different isotopes of carbon. B) are different because of the different types of hydrogen bonds that form. C) actually all have the same structure but differ in the number of electrons. D) vary because they possess different functional groups. Answer: D 4) Which of the following best explains the molecular complexity of living organisms? A) Each organism has its own unique set of monomers for use in constructing polymers. B) The large number of different monomers allows for the construction of many polymers. C) Although there are not many biological molecules in cells, each one has many different functions. D) A small number of monomers can be assembled into large polymers with many different combinations/sequences. E) Condensation reactions can create different polymers because they can combine virtually any molecules in the cell. Answer: D 5) Large biological molecules are synthesized by removing A) covalent bonds. B) carbon. C) oxygen. D) peptides. E) water. Answer: E 6) What type of chemical reaction results in the breakdown of organic polymers into their respective subunits? A) Condensation B) Oxidation C) Ionization D) Hydrolysis Answer: D

7) Which of the following reactions is an example of dehydration synthesis? A) Fat → fatty acids + glycerol B) Glucose + galactose → lactose C) Cellulose → glucose D) Peptide → alanine + glycine E) Glycogen → glucose subunits Answer: B 8) Which of the following best summarizes the relationship between dehydration reactions and hydrolysis? A) Dehydration reactions assemble polymers, and hydrolysis breaks them down. B) Dehydration reactions can occur only after hydrolysis. C) Hydrolysis creates polysaccharides, and dehydration creates monosaccharides. D) Hydrolysis creates monomers, and dehydration reactions destroy them. E) Dehydration reactions occur only in animals, and hydrolysis reactions occur only in plants. Answer: A 9) In dehydration synthesis, the atoms that make up a water molecule come from A) both of the reactants. B) enzymes. C) only one of the reactants. D) carbohydrates. E) oxygen. Answer: A 10) If digestion is , then synthesis is A) organic; inorganic B) dehydration synthesis; hydrolysis C) hydrolysis; dehydration synthesis D) inorganic; organic

Answer: C 11) Hydrolysis may be correctly described as the A) removal of water from a polymer. B) breaking of a compound into its subunits by using water to break the bond between monomers. C) constant removal of hydrogen atoms from a carbohydrate. D) heating of a compound in order to drive off its excess water and to concentrate its volume. Answer: B 12) Keratin and silk are examples of A) carbohydrates; proteins B) proteins; carbohydrates C) proteins; lipids D) nucleic acids; lipids

, whereas glucose and maltose are examples of

Answer: B 13) Dehydration synthesis involves the removal of a hydrogen ion and a hydroxyl ion. What happens next? A) The hydrogen and hydroxyl ions combine to form water. B) A large polymer is split apart into small monomers. C) A polysaccharide is released from a monosaccharide. D) The hydrogen ion becomes an isotope. Answer: A 2

14) Which molecule is a disaccharide? A) Lactose B) Fructose C) Glucose D) Water Answer: A 15) The carbohydrate in DNA is A) glucose. B) ribose. C) cellulose. D) phosphate. E) deoxyribose. Answer: E 16) Maltose is made from A) glucose and galactose. B) two glucose molecules. C) glucose and fructose. D) two peptides. Answer: B 17) The fiber in your diet is actually A) starch. B) cellulose. C) ATP. D) protein. E) glycogen. Answer: B 18) Chitin is an example of a A) nucleic acid. B) peptide. C) polysaccharide. D) triglyceride. E) monomer. Answer: C 19) Where is glycogen stored in vertebrate animals? A) Liver and muscles B) Pancreas and blood C) Fat cells D) Teeth and bones E) Brain and kidneys Answer: A

20) An example of a structural polysaccharide is A) cellulose. B) maltose. C) glucose. D) glycogen. E) starch. Answer: A 21) Which of the following provides long-term energy storage for plants? A) Cellulose B) ATP C) Starch D) Glucose E) Glycogen Answer: C 22) Lactose is a disaccharide of glucose and galactose, and its digestion requires the actions of the enzyme lactase. If lactose is eaten as part of the diet but is not digested by lactase, this sugar is then metabolized by bacteria in the intestine, leading to the symptoms of lactose intolerance. Lactose intolerance, therefore, results from a(n) A) lack of dehydration synthesis of lactose. B) low blood lactose level. C) inability of the body to produce lactose. D) lack of hydrolysis of lactose. Answer: D 23) In humans, dental cavities form when Streptococcus mutans bacteria in the mouth hydrolyze sucrose. Which of the following is (are) the products of this reaction? A) Glucose and galactose B) Glucose and fructose C) Glycogen D) Starch Answer: B 24) Which of the following can serve as an energy source and as structural support in plant cells? A) Lipids B) Carbohydrates C) Proteins D) Nucleic acids Answer: B 25) Which of the following categories includes monosaccharide monomers? A) Proteins B) Nucleic acids C) Carbohydrates D) Lipids Answer: C

26) When the level of glucose in your blood is high, your body is able to store excess glucose in the liver by forming glycogen. When blood glucose levels fall, this stored glucose can be released. Based on this information, which of the following is TRUE? A) Glucose is a polysaccharide that can join to form the monosaccharide glycogen. B) Glycogen is a polysaccharide formed by joining excess monosaccharides of glucose. C) Glycogen is a highly branched functional group that forms a larger glucose polymer. D) Glucose is not an organic molecule, but glycogen is an organic molecule. Answer: B 27) Which type of lipid is most important in biological membranes? A) Fat B) Wax C) Steroid D) Oil E) Phospholipid Answer: E 28) Which of the following is insoluble in water? A) Salt B) Olive oil C) DNA D) Amino acids E) Sucrose Answer: B 29) Cholesterol, testosterone, and estrogen are examples of A) nucleic acids. B) waxes. C) steroids. D) fatty acids. E) proteins. Answer: C 30) Triglycerides are A) made from glycerol and fattyacids. B) always composed of carbon rings. C) polymers of amino acids. D) a main component of cellularmembranes. E) hydrophilic. Answer: A 31) When 1 gram of each of these food sources is consumed, which yields the greatest amount of energy in calories? A) Polypeptide B) Glucose C) Fat D) Sucrose E) Phenylalanine Answer: C

32) Fats and oils are madeof A) three fatty acids and oneglycerol. B) three glycerols and three fatty acids. C) one glycogen and two phospholipids. D) three amino acids and oneglycerol. E) two fatty acids and one carboxyl acid. Answer: A 33) What property of phospholipids makes them important in cell membranes? A) They are an important energy carrier molecule. B) They are part of DNA. C) They have a polar end and a nonpolar end. D) They contain nucleic acids. E) They are found only in animals. Answer: C 34) Lard is a solid fat at room temperature. What does this tell you about the triglycerides in lard? A) Lard is composed of unsaturatedfats. B) The fats in lard are mostly phospholipids. C) The fats in lard are not organic molecules. D) Lard is composed of saturated fats. Answer: D 35) New government regulations require that foods containing trans fats be labeled appropriately. A trans fat is formed when food manufacturers turn liquid oils into solid fats by adding hydrogen to vegetable oils. This hydrogenation process produces a solid fat because adding the hydrogen A) forms a wax molecule. B) causes a phospholipid to form. C) allows fats to form tertiary and quaternary structures. D) allows the fatty acid chains to pack together more tightly. Answer: D 36) All of the following lipids or lipid components are hydrophobic EXCEPT A) unsaturated fats. B) fatty acid tails. C) waxes. D) fatty acid heads. E) saturated fats. Answer: D 37) The fat substitute Olestra contains a sucrose backbone with six to eight fatty acids attached. How is this different from a naturally occurring fat? A) It isn't; Olestra and natural fats have the same structure, just different tastes. B) Naturally occurring fats contain a glycerol, two fatty acids, and a phosphate group. C) Naturally occurring fats contain a sucrose backbone and three fatty acid chains. D) Naturally occurring fats contain a glycerol and three fatty acids. Answer: D

38) Two categories of organic compounds typically provide energy for living systems. Representatives of these two classes are A) lipids and proteins. B) carbohydrates and lipids. C) carbohydrates and proteins. D) proteins and nucleic acids. E) carbohydrates and nucleic acids. Answer: C 39) Imagine that you have isolated a mysterious liquid from a sample of food. You add the liquid to a beaker of water and shake vigorously. After a few minutes, the water and the other liquid separate into two layers. To which class of biological molecules does the unknown liquid most likely belong? A) Carbohydrates B) Nucleic acids C) Enzymes D) Lipids E) Proteins Answer: D 40) Cell membranes are an example of a lipid bilayer. In this lipid bilayer, both the outside of the cell and the inside of the cell are in nature. A) charged B) polar C) hydrophilic D) watery E) hydrophobic Answer: E 41) Which of the following biological molecules possess large nonpolar regions, making them insoluble in water? A) Proteins B) Nucleic acids C) Carbohydrates D) Lipids Answer: D 42) Which of the following groups is crucial to the structure and function of the sex hormones estrogen and testosterone? A) Carbohydrates B) Nucleic acids C) Lipids D) Proteins Answer: C 43) Which of the following is TRUE aboutwaxes? A) They are saturated fats and are solid at normal outdoor temperatures. B) They are unsaturated and most similar to proteins. C) They are a type of complex carbohydrate. D) They are an important food source, and most animals have enzymes for breaking them down. Answer: A

44) Which of the following statements about lipids is incorrect? A) They are used for energystorage. B) They are primary component of cell membranes. C) They are hydrophobic and waterinsoluble. D) They are short chains of polar hydrocarbons. E) They are large chains of nonpolar hydrocarbons. Answer: D 45) HDL and LDL are different types of cholesterol found in the blood. These compounds are A) carbohydrates. B) nucleic acids. C) lipids. D) proteins. Answer: C 46) The group of biological molecules that are most diverse in function is A) lipids. B) nucleic acids. C) proteins. D) carbohydrates. Answer: C 47) Enzymes are specialized A) carbohydrates B) lipids C) nucleic acids D) proteins

that catalyze chemical reactions within the body.

Answer: D 48) Proteins are constructed using how many different amino acids? A) 4 B) 1,000 C) 100 D) 20 E) More than 5,000 Answer: D 49) The specific function of a protein is determined by the A) hydrophilic head attached to the hydrophobic tail. B) number of peptide bonds itcontains. C) fatty acids that are joined together in the polypeptide. D) number of disulfide bonds. E) exact sequence of amino acids. Answer: E 50) What do carbohydrates, lipids, and proteins have in common? A) All are important enzymes that function within the cell. B) All are inorganic molecules. C) Covalent bonding holds these molecules together. D) Polymers of these organic molecules form monomers via dehydration synthesis reactions. Answer: C 8

51) A peptide bond forms between which of these groups? A) Carboxyl and amino B) Hydroxyl and carboxyl C) Carboxyl and aldehyde D) Phosphate and hydroxyl E) Amino and aldehyde Answer: A 52) All of the following are polysaccharides EXCEPT A) glycogen. B) chitin. C) starch. D) glucose. Answer: D 53) What maintains the secondary structure of a protein? A) Peptide bonds B) Hydrogen bonds C) Ionic bonds D) Disulfide bonds Answer: B 54) Complex, three-dimensional, tertiary structures of proteins result from A) hydrogen and disulfide bonds. B) ionic bonds. C) hydrogen bonds. D) ionic and hydrogen bonds E) disulfide bonds. Answer: A 55) The four polypeptides that are joined together to make functional hemoglobin represent which level of protein organization? A) Quaternary structure B) Primary structure C) Secondary structure D) Tertiary structure Answer: A 56) Which of the following is an example of a protein? A) Cellulose B) Estrogen C) Keratin D) ATP Answer: C

57) Which type of molecule is most abundant in a typical cell? A) Water B) Lipid C) Carbohydrate D) Nucleic acids E) Protein Answer: A 58) Which of the following refers to the amino acid sequence of proteins? A) Primary B) Secondary C) Tertiary D) Quaternary Answer: A 59) The bonding of two amino acid molecules to form a larger molecule requires which of the following? A) Formation of a hydrogen bond B) Both removal of a water molecule and formation of a hydrogen bond C) Removal of a water molecule D) Formation of a glycosidic bond E) Addition of a water molecule Answer: C 60) A denatured protein differs from a normal protein because it A) has lost its usual secondary and tertiary structures. B) does not contain amino acids. C) is composed of nucleotides. D) contains many disulfide bonds. Answer: A 61) Which of the following biological molecules are composed of amino acid subunits? A) Proteins B) Nucleic acids C) Lipids D) Carbohydrates Answer: A 62) Which of the following may possess primary, secondary, tertiary, and quaternary structures? A) Nucleic acids B) Carbohydrates C) Proteins D) Lipids Answer: C 63) Your classmate is trying to keep all the facts about biological molecules straight. He asks you to explain how amino acids and proteins are related. What do you tell him? A) Proteins are a portion of an amino acid. B) Amino acids are formed by joining together many proteins. C) Proteins are chains of carbohydrates, and amino acids are a type of lipid. D) Proteins are made up of chains of amino acids. Answer: D 10

64) Your friend is trying to learn about how to kill bacteria. She reads that preservatives such as citric acid are added to foods because the acidic environment kills bacteria by denaturing their proteins. She thinks this sounds like a lot of scientific jargon and asks you what it means. How can you explain it in simpler terms? A) Denaturing refers to the fact that the bacterial cells divide too quickly and die. B) Denaturing means that the proteins of the bacteria lose their structure and can't function, so the bacteria die. C) Denaturing their proteins means that the proteins in bacteria are converted into carbohydrates. D) The acid causes the cells to swell and burst open, also known as denaturation. Answer: B 65) Scientists consider prions to be "puzzling" proteins. Which of the following is TRUE about prions? A) Prions are noninfectious proteins. B) Prions are proteins that cause nearby proteins to change shape and become infectious. C) Prions are infectious proteins that cannot be denatured by any amount of heat. D) Prions are proteins that are denatured more easily than most proteins. Answer: B 66) Which of the following correctly matches an organic polymer with its monomers, respectively? A) Hydrocarbon; monosaccharides B) DNA; ATP C) Carbohydrate; polysaccharides D) Lipid; steroids E) Protein; amino acids Answer: E 67) The "backbone" of a nucleic acid molecule is made of A) sugar and phosphate groups. B) ATP molecules. C) lipids. D) NAD+ and FAD. E) amino acids. Answer: A 68) DNA carries genetic information inits A) sugar groups. B) tertiary structure. C) sequence of bases. D) helical form. E) phosphate groups. Answer: C 69) How many hydrogen bonds exist between a G-C base pair? A) 1 B) 2 C) 3 D) 4 Answer: C

70) Adenosine triphosphate (ATP) is an example of a(n) A) inorganic molecule. B) nucleotide. C) lipid. D) carbohydrate. E) protein. Answer: B 71) A nucleotide is made ofa A) phospholipid, sugar, and protein. B) phospholipid, sugar, and nitrogenous base. C) phosphate, protein, and nitrogenous base. D) phosphate, sugar, and nitrogenous base. Answer: D 72) Which of these is NOT a nucleic acid or nucleotide? A) LDL B) ATP C) DNA D) RNA Answer: A 73) Suppose you have discovered a new virus and have isolated its nucleic acids. What feature could you look for to determine whether the nucleic acids of this virus are RNA or DNA? A) If it is RNA, it will containribose. B) If it is RNA, there will be no adenine. C) If is RNA, it will contain deoxyribose. D) If it is DNA, the virus will not contain proteins. Answer: A 74) Which of the following biological molecules are composed of monomer units containing a sugar, a phosphate group, and a nitrogen-containing base? A) Proteins B) Nucleic acids C) Carbohydrates D) Lipids Answer: B 75) Which of these biological molecules contain genetic information? A) Carbohydrates B) Nucleic acids C) Proteins D) Lipids Answer: B 76) Functional groups determine the characteristics and chemical reactivity of organic molecules. A) True B) False Answer: A

77) Phospholipids have hydrophilic tail regions and hydrophobic head regions. A) True B) False Answer: B SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 78) Carbon provides a backbone for a variety of biological molecules. Carbon can typically form bonds.

covalent

Answer: four 79) Important biological molecules that have a carbon backbone bonded to hydrogen atoms are considered to be . Answer: organic 80) Many biological molecules are formed by the joining of monomer units in a(n) water); the reverse process is called .

reaction (removalof

Answer: dehydration synthesis; hydrolysis 81) Fatty acids thatcontaindouble-bonded carbonatoms are called

Answer: unsaturated 82) The linear arrangement of amino acids in a polypeptide chain is referred to as the protein.

structure of the

Answer: primary 83) Proteins are formed by joining amino acids together into a polymer. A one amino acid with the carboxyl end of another.

bond joins the amino end of

Answer: peptide 84) RNA differs from DNA in that RNA contains the sugar

Answer: ribose 85) What are the four major types of biological molecules? Answer: carbohydrates, lipids, proteins, and nucleic acids 86) Why can cows break down cellulose into glucose subunits, but humans cannot? Answer: Cows lack the ability to break down cellulose, but they have special microbes in their digestive tracts that break down cellulose for them; humans do not. 87) What are the two main functions of carbohydrates in a living system? Give an example of each. Answer: energy storage (glucose, starch, glycogen) and structural support (chitin, cellulose) 88) Why is it an advantage for animals that migrate long distances to store energy as lipids rather than carbohydrates? Answer: Lipids (fats) store more than twice as much energy as carbohydrates.

89) Describe the differences between saturated and unsaturated fatty acids. Which is most likely to be solid at room temperature? Why? Answer: Saturated fats have only single C-C bonds, whereas unsaturated fats have at least one double C-C bond. The saturated fatty acids are most likely to be solid at room temperature because the fatty acid chains can be packed together more tightly. 90) Explain how a saturated fat is structurally different from an unsaturated fat. Answer: A saturated fat has three fatty acids that are saturated with hydrogens, and the tails are able to be straight and packed closely together. Unsaturated fats are not fully saturated with hydrogens and contain bonds that cause bends or kinks in the fatty acid chains, so they cannot pack tightly together. 91) How do two amino acids, such as lysine and methionine, differ from each other? Answer: They have different functional (or "R") groups. 92) You have curly hair, and your brother has straight hair. Describe how the proteins of your curly hair are different from the proteins of his straight hair. Answer: The keratin proteins in your curly hair have disulfide bonds in certain locations that cause the keratin to have bends or curls. The disulfide bonds in your brother's straight hair are in locations that don't cause bends in the keratin, so there are no curls. 93) Which nucleotide molecule functions as an energy carrier in the cell? Answer: ATP 94) What are some of the similarities and differences between DNA and RNA? Answer: DNA uses the nucleotides A-T-G-C, and RNA uses the nucleotides A-U-G-C. DNA uses a deoxyribose sugar, and RNA uses a ribose sugar. DNA is usually double-stranded, and RNA is usually single-stranded.

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 95) As shown in this figure, the top triglyceride (a) has

, whereas the bottom triglyceride (b) has

A) no double bonds and is unsaturated; double and/or triple bonds and is saturated B) no double bonds and is saturated; double and/or triple bonds and is unsaturated C) double bonds and is saturated; no double and/or triple bonds and is unsaturated D) double bonds and is unsaturated; no double and/or triple bonds and is saturated Answer: B

96) As shown in this figure, the valine and lysine in this protein are linked by covalent bonds within the structure, whereas the hydrogen bonds hold together molecules within the helical structure.

A) primary; tertiary B) secondary; quaternary C) tertiary; quaternary D) primary; secondary E) secondary; tertiary Answer: D Soap and detergent molecules have a long, hydrophobic tail and a polar, hydrophilic head. They are sometimes referred to as bridge molecules because they allow oils and fats to be suspended and dissolved in water (which they otherwise would not be able to do). Imagine that you are using soap to wash away dirt that is being held against your skin in an oily film. 97) In this scenario, what is the most likely procedure beer makers use to produce alcohol from starchy grains? A) The starch is converted into glycogen, which is easier for the yeast to digest. B) The starch is converted into a polymer of many glucose molecules before being used. C) Water is used to break the bonds between glucose subunits in the starch, in a form of dehydration synthesis. D) The starch is broken down into mono- and/or disaccharides by hydrolysis before use. Answer: D

98) In this scenario, how are the soap, dirt/oil, and water arranged at the molecular level? A) The soap molecules encase the dirt/oil within a small droplet that has a hydrophobic exterior and a hydrophilic interior. B) The soap is converted into a lipid that binds to the dirt/oil while repelling the water. C) The soap molecules encase the dirt/oil within a small droplet that has a hydrophilic exterior and a hydrophobic interior. D) Water and dirt/oil form covalent bonds inside a small droplet that has a soap-based outer membrane. Answer: C

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Which type of microscope has the best resolution? A) An electron microscope B) Hooke's microscope C) Leeuwenhoek's microscope D) A modern light microscope Answer: A 2) Which of the following statements does NOT agree with the cell theory? A) A balanced diet is important for good health. B) Paramecium comes from Paramecium. C) The smallest living organisms are single cells. D) Spontaneous generation of cells cannot occur. E) Insects are composed of cells. Answer: A 3) Which of the following components is NOT part of the modern cell theory? A) The smallest living organisms are single cells. B) All cells arise from preexisting cells. C) Cells are the functional units of multicellular organisms. D) Bacteria are examples of eukaryotic cells. E) All living organisms are made up of one or more cells. Answer: D 4) What is NOT a feature of a prokaryotic cell? A) A plasma membrane B) Enzymes C) A nuclear membrane D) DNA E) Ribosomes Answer: C 5) Of the items listed, which is the smallest that you can see with the unaided eye? A) DNA molecule B) Human skin cell C) Virus D) Ribosomes E) Frog embryo Answer: E 6) Phospholipids are A) made on the ribosomes. B) completely hydrophobic. C) found in cell membranes. D) completely hydrophilic. Answer: C

7) All cells possess all of the following components EXCEPT A) ribosomes. B) cytoplasm. C) a nuclear membrane. D) a plasma cell membrane. E) genetic material (DNA or RNA). Answer: C 8) The cytoplasm of eukaryotic cells contains all of the following EXCEPT A) water. B) chromosomes. C) organelles. D) enzymes. E) dissolved nutrients. Answer: B 9) The phospholipids that make up the plasma membrane have A) prokaryotic; eukaryotic B) eukaryotic; prokaryotic C) hydrophobic; hydrophilic D) hydrophilic; hydrophobic E) cytoplasmic; phagocytic

heads and

Answer: D 10) The major histocompatibility complex (MHC) is an example of a(n) A) organelle. B) polysaccharide. C) phospholipid. D) glycoprotein. Answer: D 11) Which of the following is the smallest? A) Virus B) Mitochondrion C) Prokaryotic cell D) Eukaryotic cell Answer: A 12) Which of the following is so small, it is visible only with an electron microscope? A) Prokaryotic cell B) Mitochondrion C) DNA D) Eukaryotic cell Answer: C 13) Flagellated cells can A) divide more quickly than nonflagellatedcells. B) move the cell through fluid. C) attach to surfaces more effectively because of theflagella. D) move internal organelles more efficiently than nonflagellated cells. Answer: B 2

tails.

14) Membrane proteins are synthesized on ribosomes that are located A) on the Golgi apparatus. B) in the cytoplasm. C) in the nucleus. D) on the smooth endoplasmic reticulum. E) on the rough endoplasmic reticulum. Answer: E 15) A mutant plant cell with no chloroplasts would A) synthesize new chloroplasts in thenucleus. B) appear green in color. C) still be able to use carbohydrates as an energy source for a short period of time. D) still be able to capture energy as sunlight. Answer: C 16) Plastids are found in A) plant B) fungal C) bacterial D) animal

cells.

Answer: A 17) Which of the following is NOT a function of plastids? A) Extracting energy from food and converting it to ATP B) Storing pigments C) Storing photosynthetic products D) Carrying out photosynthesis Answer: A 18) Of the following cell components, which is composed of protein fibers that provide shape and organization to eukaryotic cells? A) Golgi complex B) Cytoskeleton C) Mitochondria D) DNA E) Chromatin Answer: B 19) What primarily determines the shape of animal cells, which lack cell walls? A) Cytoskeleton B) Cytoplasm C) Nucleus D) Ribosomes E) Endoplasmic reticulum Answer: A

20) All the following are important functions of the cytoskeleton EXCEPT A) assistance during cell division. B) storage of food molecules. C) movement of organelles. D) maintenance of organization in the cell. E) maintenance of shape. Answer: B 21) Fibers of the cytoskeleton are composed of primarily A) ER. B) nucleic acids. C) proteins. D) lipids. E) polysaccharides. Answer: C 22) Which of the following does NOT possess a double membrane? A) Nuclear envelope B) Chloroplast C) Ribosome D) Mitochondrion E) Plastid Answer: C 23) Which organelle is most abundant in cardiac muscle cells? A) Smooth ER B) Mitochondria C) Lysosomes D) Plastids E) Golgi complexes Answer: B 24) A nucleolus is A) an area where the nucleus is synthesized. B) an extra nucleus in thecell. C) an area in the nucleus of eukaryotic cells where ribosomes are synthesized and assembled. D) a membrane-bound organelle. E) the area in a prokaryote where DNA is concentrated. Answer: C 25) The nucleus of a eukaryotic cell is characterized by A) a triple-layer membrane. B) a nonporous membrane. C) a double membrane. D) a single-layered membrane. Answer: C

26) Choose the correct pathway of information flow in the cell. A) ER → DNA → Golgi → protein B) ER → DNA → RNA → protein C) DNA → RNA → protein D) RNA → DNA → protein Answer: C 27) What is the difference between free and attached ribosomes? A) Free ribosomes are located in the cytoplasm, whereas attached ribosomes are embedded on the endoplasmic reticulum. B) Free ribosomes produce proteins that are exported from the cell, whereas attached ribosomes make proteins for mitochondria and chloroplasts. C) Free ribosomes produce proteins, whereas attached ribosomes produce carbohydrates. D) Free ribosomes are readily "used up" by the cell and are replaced frequently, whereas attached ribosomes remain functional for the lifetime of the cell. Answer: A 28) If all of the lysosomes within a cell suddenly ruptured and released their contents, what could occur? A) The DNA within the mitochondria would begin to degrade. B) The number of proteins in the cell would begin to increase. C) The biological molecules in the cell would begin to degrade. D) The mitochondria and chloroplasts would begin to divide. E) There would be no change in the normal function of the cell. Answer: C 29) If a cell contains large amounts of rough endoplasmic reticulum (ER), then A) large amounts of protein hormones could be produced and exported by the cell. B) membrane lipids could be produced by that cell. C) membrane proteins and phospholipids are lacking in the cell. D) few, if any, enzymes for biochemical processes are manufactured by that cell. E) digestive enzymes cannot be manufactured by that cell. Answer: A 30) Cells that primarily produce steroid hormones, such as testosterone and estrogen, have large quantities of A) enzymes. B) smooth endoplasmic reticulum. C) DNA. D) cytoplasmic ribosomes. E) plasma membranes. Answer: B 31) Ribosomes are the site of A) protein B) nucleoli C) DNA D) RNA E) glucose

synthesis.

Answer: A

32) Which of the following is associated with rough ER? A) Plasma membrane B) Ribosomes C) Chlorophyll D) DNA E) Lipid synthesis Answer: B 33) The Golgi apparatus packagesmaterials into A) vesicles B) vacuoles C) nucleoli D) plastids E) organelles

for transport or export.

Answer: A 34) Which cellular organelle packages enzymes and forms lysosomes? A) Mitochondrion B) Smooth ER C) Golgi apparatus D) Rough ER Answer: C 35) How does a cell rid itself of defective or malfunctioning organelles? A) Defective organelles accumulate until the cell itself dies. B) The organelles are exported byphagocytosis. C) Lysosomes assist in the removal of defective organelles by digesting them. D) The organelles are engulfed by plastids and stored. E) Ribosomes remove malfunctioning organelles by degrading the parts. Answer: C 36) Which statement most accurately describes the interactions among ER, ribosomes, and Golgi bodies in exporting protein from the cell? A) Golgi bodies manufacture proteins, which travel through the ER to be packaged by the ribosomes for export. B) Ribosomes make proteins that travel through the Golgi bodies to the ER, which exports them. C) ER manufactures proteins, which are carried by ribosomes to the Golgi bodies for export. D) ER manufactures proteins, which are carried by the Golgi bodies to the ribosomes for export. E) Ribosomes manufacture proteins, which travel through the ER and are packaged by the Golgi bodies for export. Answer: E 37) Which of the following "buds off" of the Golgi complex? A) Cytoskeleton B) Ribosomes C) Nuclei D) Vesicles E) Cells Answer: D

38) A cell with a large number of lysosomes would most likely be very active in A) phagocytosis. B) movement. C) lipid synthesis. D) cell division. Answer: A 39) Researchers have been able to study the pathway of a secreted protein by "tagging" it with a fluorescent marker. Using this method, you would observe fluorescence moving from the ER to which organelle? A) Lysosome B) Mitochondria C) Plasma membrane D) Golgi apparatus E) Nuclear membrane Answer: D 40) What is the function of a plant cell vacuole? A) Replicates chromosomes B) Initiates division of the cell C) Stores water D) Packages proteins forexport Answer: C 41) A plant cell adapted for waste storage would probably contain a large number of A) ER. B) mitochondria. C) ribosomes. D) nuclei. E) vacuoles. Answer: E 42) All of the following cells contain mitochondria EXCEPT A) prokaryotic cells. B) plant cells. C) animal cells. D) eukaryotic cells. Answer: A 43) Which of the following provides evidence that mitochondria and chloroplasts were once free-living prokaryotic organisms? A) They capture the energy of sunlight to make ATP. B) They contain nucleoids. C) They produce digestive enzymes on their rough ER. D) They contain their own DNA, independent of the nucleus. Answer: D

44) All of the following are characteristics of mitochondria and chloroplasts EXCEPT A) both synthesize ATP. B) both can capture the energy of sunlight. C) both likely evolved from prokaryoticbacteria. D) both are surrounded by a double membrane. E) both possess their own DNA, independent of the nucleus. Answer: B 45) Which pair of organelles is responsible for supplying energy (in the form of ATP) to eukaryotic cells? A) Chloroplasts and mitochondria B) Mitochondria and lysosomes C) Chloroplasts and ribosomes D) Golgi apparatus and ribosomes E) Ribosomes andmitochondria Answer: A 46) The organelle that extracts energy in food to produce ATP energy is the A) mitochondrion. B) cytoplasm. C) chloroplast. D) nucleus. E) ribosome. Answer: A 47) Which of the following is capable of converting solar energy into chemical energy? A) Golgi apparatus B) Mitochondria C) Vesicles D) Chloroplasts E) Vacuoles Answer: D 48) Which of the following relationships is FALSE? A) Mitochondria-formation of ATP B) Ribosomes-site of protein synthesis C) Nucleus-genetic information D) Cell wall-support and protection E) Chloroplasts-chief site of lipid synthesis Answer: E 49) Which of the following is the thinnest? A) A microtubule B) A flagellum C) A microfilament D) An intermediate filament Answer: C

50) A particular cell has the following molecules and structures: enzymes, DNA, ribosomes, plasma membrane, and mitochondria. It couldbe a(n) cell. A) animal, but not a plant B) plant, but not an animal C) plant or bacterial D) plant or animal E) bacterial Answer: D 51) A cell from a wheat plant contains all of the following EXCEPT a A) flagellum. B) chloroplast. C) cell wall. D) cytoskeleton. E) mitochondrion. Answer: A 52) All of the following are dependent on cilia EXCEPT the A) gills of oysters. B) oviduct in mammals. C) sperm of animals. D) respiratory tract ofvertebrates. Answer: C MATCHING. Choose the item in column 2 that best matches each item in column 1. For the following question(s), select the organelle that is the most appropriate match for each description. Selections may be used once, more than once, or not at all. 53) Digests damaged organelles

A) Smooth endoplasmic reticulum

Answer: D B) Rough endoplasmic reticulum 54) Sorts proteins and sends them to their proper destination

C) Mitochondrion

Answer: E D) Lysosome 55) Site of protein synthesis Answer: B

E) Golgi apparatus

56) Makes steroid hormones Answer: A 57) Responsible for most of a muscle cell's ATP generation Answer: C

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 58) Both prokaryotic and eukaryotic cellspossess A) a nucleus. B) mitochondria. C) chloroplasts. D) ribosomes. Answer: D 59) Which is a difference between prokaryotes and eukaryotes? A) Prokaryotes have a nucleus, whereas eukaryotes have a nucleoid. B) Prokaryotes have DNA, whereas eukaryotes have RNA. C) Prokaryotes have a nucleoid, whereas eukaryotes have a nucleus. D) Prokaryotes have RNA, whereas eukaryotes have DNA. E) Prokaryotes have a cell wall, but eukaryotes do not. Answer: C 60) Which of the following cell structures is NOT found in a bacterial cell? A) Ribosomes B) Plasma membrane C) Cell wall D) DNA E) Central vacuole Answer: E 61) If you removed the sex pili from a bacterial cell, then the A) bacterium could no longer exchange DNA with other cells. B) bacterium could no longer swim. C) shape of the bacterium wouldchange. D) bacterium would dry out. E) bacterium could no longer regulate the movement of molecules into and out of the cell. Answer: A 62) Prokaryotes that are rod-shaped arecalled A) spirilla. B) bacilli. C) cocci. D) eukaryotes. Answer: B 63) Prokaryotic cells do NOT have A) genes. B) ribosomes. C) flagella. D) cilia. E) cytoplasm. Answer: D

64) The small, circular loops of DNA in prokaryotic cells that are separate from the main chromosome and may carry genes associated with antibiotic resistance are called A) pili. B) ribosomes. C) plasmids. D) cristae. E) plastids. Answer: C 65) Which of the following is a FALSE statement about prokaryotes? A) Prokaryotes are so small that they can be seen only with a high-power electron microscope. B) Prokaryotic cells contain ribosomes. C) Prokaryotes have a plasma membrane, similar to that of eukaryotes. D) Prokaryotes may contain extra genes in plasmids. Answer: A 66) Prokaryotic cells do not have mitochondria, so they cannot make ATP energy. A) True B) False Answer: B SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 67) The fluid portion of the cytoplasm of a cell is the

Answer: cytosol 68) Cells that have a nucleus are referred to as cells.

cells; those that lack a membrane-bound nucleus are called

Answer: eukaryotic; prokaryotic 69) A cell that contains a large number of ribosomes would produce a large number of

molecules.

Answer: protein 70) RNA carries information for protein synthesis from the DNA in the nucleus to the ribosomes in the cytoplasm. To get from the nucleus to the cytoplasm, RNA must pass through a in the nuclear membrane. Answer: nuclear pore 71) The is an organelle that extracts energy from food molecules and converts it into ATP; the an organelle that captures solar energy and converts it into food energy. Answer: mitochondrion; chloroplast 72) The is an organelle in which some of the proteins synthesized on ribosomes and rough ER are modified and packaged. Answer: Golgi apparatus 73) Some bacteria, including many that cause disease, attach to surfaces using external and/or hair-like protein strands called attachment . Answer: capsules; layers; pili

or slime

74) The DNA in a prokaryotic cell is in the

region of the cytoplasm.

Answer: nucleoid 75) What are the three main components of modern cell theory? Answer: All living organisms are composed of one or more cells, the cell is the smallest functional unit of life, and all cells come from preexistingcells. 76) What size, in diameter, are most single cells? Answer: From 1 to 100 micrometers (millionths of a meter) 77) What components do all cellspossess? Answer: DNA (at some point in their life cycle), a cell membrane, ribosomes, and cytoplasm 78) Describe the main functions of the plasma membrane. Answer: The plasma membrane isolates the cell's internal environment from the external environment, regulates the flow of materials into and out of the cell, and allows for interaction with other cells. 79) Why are cells generally small? Answer: Cells need sufficient surface area for the exchange of nutrients and wastes with the external environment. 80) Imagine that a protein molecule is to be exported from a cell. Describe the pathway that the protein takes from the point of synthesis toexport. Answer: A protein to be exported is synthesized by a ribosome on the rough endoplasmic reticulum. From there it travels via transport vesicle to the Golgi apparatus for processing. From the Golgi apparatus it travels, again via vesicle, to the plasma membrane for release outside the cell. 81) When a cell grows, it must produce more plasma membrane material. How does the cell do this? Answer: An ER vesicle is sent off to the Golgi apparatus. The Golgi apparatus repackages the contents and sends a new vesicle to fuse with the plasma membrane, which helps to create more plasma membrane. 82) How is the vacuole involved in the support of the non-woody parts of the plant? Answer: The vacuole allows for the buildup of turgor pressure in plant cells, which prevents wilting. 83) Why is the cytoskeleton such an important structural component of cells? Answer: The cytoskeleton maintains cell shape, facilitates cell and organelle movement, and is involved in cell division. 84) Briefly describe the similarities and differences between cilia and flagella. Answer: Both are slender extensions of the cell membrane. Flagella are longer than cilia and usually fewer in number. Both are made from an array of microtubules, and both arise from centrioles that move to the plasma membrane to form basal bodies. Cilia provide a force that is parallel to the plasma membrane. They function in moving substances across the surface of the cell and sometimes in movement of the entire cell. Flagella exert a force perpendicular to the plasma membrane and are involved in movement of the entire cell. 85) Compare and contrast plant and animal cell structure. Include at least two similarities and two differences. Answer: See Table 4.1 in the text for a listing of the differences. The answer should include some of the following characteristics: plant cells have chloroplasts, a cell wall, and a central vacuole; animal cells have lysosomes; both types of cell have rough and smooth ER, a nucleus, ribosomes, and mitochondria.

86) Describe the differences among the nucleolus, nucleus, and nucleoid regions in cells. Answer: In eukaryotes, the nucleus contains the DNA, and the nucleolus region in the nucleus is the site of ribosome synthesis. The nucleoid region is the site in prokaryotic cells where the single circular chromosome is contained in the cytoplasm. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 87) The food particles shown in this figure are being ingested by

A) endocytosis and digested with enzymes produced at the lysosomes. B) endocytosis and digested with enzymes produced at the ribosomes. C) exocytosis and digested with enzymes produced at the ribosomes. D) exocytosis and digested with enzymes produced at the lysosomes. Answer: A

88) The cell shown in this figure must be

A) an exception to the celltheory. B) a prokaryote. C) from a plant. D) from a eukaryote. Answer: D 89) Treponema pallidum is the organism that causes syphilis, a sexually transmitted disease. This organism moves around freely, making it well adapted to traveling within bodily fluids and being spread from host to host during intimate contact. It possesses a single chromosome and has relatively few genes. The overall shape of this single-celled organism is similar to a corkscrew, with many twists and turns along its length. Based on this information, Treponema is most likely what type of cell? A) A prokaryotic spirillum B) A flagellated eukaryote C) A ciliated eukaryote D) A prokaryotic bacillus E) A prokaryotic coccus Answer: A

90) The ribosomes in eukaryotic cells are larger than the ribosomes in prokaryotic cells. Furthermore, eukaryotic ribosomes are not affected by some chemicals that affect prokaryotic ribosomes, a fact that can be put to good use by microbiologists seeking new antimicrobial drugs. An example of this is the antibiotic erythromycin, which prevents protein synthesis by prokaryotic ribosomes but does not affect eukaryotic ribosomes at all. Thus, erythromycin kills bacteria but does not affect humans or other animals. Using this information, which of the following would be expected and would support the endosymbiont hypothesis? A) Mitochondrial ribosomes will be larger than prokaryotic ribosomes. B) Mitochondrial ribosomes will be smaller than prokaryotic ribosomes. C) The ribosomes in chloroplasts will be sensitive to erythromycin. D) Mitochondria and chloroplasts will not have ribosomes. Answer: C

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) The substances in cell membranes that form a barrier to the movement of materials across the membrane are A) internal proteins. B) carbohydrates. C) external proteins. D) lipids. E) nucleic acids. Answer: D 2) The portion of the cell membrane is responsible for the isolating function of the membrane, whereas the portion regulates exchange and communication with the environment. A) cholesterol; lipid B) carbohydrate; lipid C) lipid; protein D) protein; cholesterol E) nucleic acid; lipid Answer: C 3) When a mouse cell and a human cell are fused, the membrane proteins of the two cells become uniformly distributed over the surface of the hybrid cell. This occurs because A) all proteins are anchored within the membrane. B) all proteins in the plasma membrane come from a membrane other than the human or the mouse. C) many proteins can move around within the bilayer. D) different membranes contain different proteins. E) proteins are asymmetrically distributed within the membrane. Answer: C 4) Phospholipids spontaneously form a bilayer in an aqueous solution. Why do the heads of the phospholipids point out and the tails point toward one another? A) The tails are nonpolar and form hydrogen bonds with one another. B) The heads are repelled by the water inside and outside the cell. C) The tails are repelled by the aqueous environment, and the heads will directly interact with the aqueous solution. Answer: C 5) Plasma membranes are best described as a A) double layer of phospholipids with hydrophilic heads facing away from one another. B) single layer of phospholipids with tails pointed toward the inside of the cell. C) double layer of phospholipids with hydrophobic tails facing toward one another. D) single layer of phospholipids with water molecules attached along one side. E) double layer of phospholipids with hydrophobic tails facing away from each other (toward the cytoplasm of the cell and the extracellular solution). Answer: C 6) The hydrophobic tails of a phospholipid bilayer are oriented toward the A) cytoplasm of the cell. B) extracellular fluid surrounding the cell. C) interstitial fluid. D) interior of the plasma membrane (i.e., toward one another). E) both the extracellular fluid and cytoplasm. Answer: D

7) Which of the following accounts for the fluid aspect of the fluid mosaic model of plasma membranes? A) The plasma membrane is "fluid" because of the movement of substances across the membrane. B) The individual phospholipid molecules are not bonded to one another, so the movement of certain proteins and lipids is possible within and through the bilayer. C) The bilayer permits diffusion of certain lipid-soluble substances. D) One of the components of the membrane is water. E) The membrane is watersoluble. Answer: B 8) According to the fluid mosaic model of cell membranes, which of the following is a TRUE statement about membrane phospholipids? A) They have hydrophilic tails in the interior of the membrane. B) They occur in an uninterrupted bilayer, with membrane proteins strictly anchored to the surface of the membrane. C) They are free to depart from the membrane and are dissolved in the surrounding solution. D) They form a viscous fluid through which proteins shift and flow. E) They frequently flip-flop from one side of the membrane to the other. Answer: D 9)

In biological membranes, the phospholipids are arranged in a A) bilayer, with the fatty acids pointing toward one another. B) bilayer, with the phosphorus groups in the interior of the membrane. C) single layer, with the phosphorus-containing region facing the interior of the cell. D) bilayer, with the fatty acids facing outward (facing the interior and exterior of the cell). E) single layer, with the fatty acids facing the interior of the cell. Answer: A 10) The hydrophilic regions of a membrane protein are most likely to be found A) exposed on the surface of the cell membrane. B) in the interior of the membrane. C) only in muscle cell membranes. D) associated with the fatty acid region of the lipids. E) attached to carbohydrates and facing the interior of a cell. Answer: A 11) Suppose that plasma membranes were single layers of phospholipids rather than double layers, and the heads faced the extracellular fluid. The interior of this hypothetical cell would have to be A) hydrophobic only. B) nonpolar only. C) polar only. D) hydrophilic only. E) hydrophobic and nonpolar. Answer: E 12) What would happen if the plasma membrane were composed solely of phospholipids and no proteins? A) Simple diffusion and osmosis would continue to occur. B) Immune reactions would not beaffected. C) Only water would be able to pass through the membrane. D) The movement of molecules across the membrane would not be affected. E) All movement of molecules across the membrane would cease. Answer: A

13) ISO membranes are inside-out membrane vesicles used by researchers in membrane studies. As a molecule diffuses into the vesicle, it will encounter the layers of the membrane in the following order A) head-tail-head-tail. B) head-tail-tail-head. C) tail-head-head-tail. D) tail-head-tail-head. E) head-head-tail-tail. Answer: B 14) What structure in the membrane causes plasma membranes to resist freezing? A) Saturated fatty acid tails B) Nonpolar heads of the phospholipids C) Channel proteins D) Unsaturated fatty acid tails E) Cholesterol Answer: D 15) Within the fluid mosaic of a plasma membrane, what is the role of transport and channel proteins? A) They identify the cell. B) They may set off cellular changes such as cell division or hormone secretion. C) They are cell-surface connection sites. D) They permit ions and water molecules to move through the plasma membrane. E) They prevent the passage of amino acids. Answer: D 16) Recognition proteins are most importantfor A) maintaining membrane fluidity. B) active transport of molecules. C) facilitated diffusion of molecules. D) distinguishing foreign cells from "self" cells. E) maintaining membrane integrity. Answer: D 17) In general, which of the following is (are) largely responsible for moving substances across the plasma membrane, communicating with other cells, and identifying the cell? A) Nucleic acids B) Phospholipids C) Proteins D) Carbohydrates E) Cytoskeleton Answer: C 18) What prevents your immune system from attacking your own cells? A) Inadequate enzymes B) Cholesterol C) Receptor proteins D) Recognition proteins E) Fever Answer: D

19) The main lipids found in cell membranes are A) steroids. B) triglycerides. C) waxes. D) glycerol. E) phospholipids. Answer: E 20) Which of the following groups includes carrier and channel proteins? A) Receptor proteins B) Transport proteins C) Connection proteins D) Recognition proteins Answer: B 21) Recognition proteins, such as those embedded on the surface of red blood cells, are composed of A) nucleic acids. B) glycoproteins. C) phospholipases. D) steroids. Answer: B 22) Which of the following would NOT be found in a membrane? A) Channel protein B) Cellulose C) Phospholipid D) Receptor protein E) Cholesterol Answer: B 23) Cell membranes do all of the following EXCEPT A) regulate the movement of substances between the cytoplasm of the cell and the extracellular fluid. B) provide an energy source for the cell. C) isolate the cell's contents from the external environment. D) allow communication between cells. E) provide attachments between cells. Answer: B 24) Which of the following types of membrane proteins are responsible for facilitated diffusion? A) Transport proteins B) Enzymes C) Connection proteins D) Receptor proteins E) Recognition proteins Answer: A

25) Which of the following types of membrane proteins are responsible for maintaining cell shape by linking the membrane protein with the cytoskeleton? A) Enzymes B) Connection proteins C) Transport proteins D) Receptor proteins E) Recognition proteins Answer: B 26) Which of the following types of membrane proteins are responsible for conveying external messages such as those sent by a hormonesignal? A) Enzymes B) Receptor proteins C) Transport proteins D) Connection proteins E) Recognition proteins Answer: B 27) The net movement of molecules from a high concentration to a low concentration is best described by which of the following? A) Passive transport B) Active transport C) Osmosis D) Exocytosis E) Endocytosis Answer: A 28) For diffusion to occur, there must be A) ATP. B) a gradient. C) a membrane. D) water. Answer: B 29) The bacterium Vibrio cholerae releases a toxin that blocks a channel protein in the membranes of cells that line the intestine. This toxin prevents the movement of sodium ions from the inside of the intestine into cells. If the sodium ions could not move into the cells, how would this affect the movement of water between the inside of the intestine and the cells? A) Water would leave the cells and enter the intestines by osmosis. B) The movement of water would not be affected. C) Water would leave the cells and enter the intestines by facilitated diffusion. D) Water would leave the intestines and enter the cells by facilitated diffusion. E) Water would leave the intestines and enter the cells by osmosis. Answer: A 30) Which of the following is an energy-requiring mode of transport that brings substances into a cell? A) Active transport B) Simple diffusion C) Osmosis D) Facilitateddiffusion Answer: A

31) In reference to diffusion, passive really means A) no energy required. B) in the air. C) very slowly. D) no gradient. E) without a membrane. Answer: A 32) Imagine that you fill a shallow tray with water and place a drop of red ink in one end of the tray and a drop of green ink in the other end. Which of the following is TRUE at equilibrium? A) The red and green ink do not mix at all. B) The concentration of each ink is higher at one end of the tray than at the other end. C) The red and green inks are both uniformly distributed throughout the tray. D) No predictions can be made without knowing the size of the ink molecules. E) The red ink is uniformly distributed in one half of the tray, and the green ink is uniformly distributed in the other half of thetray. Answer: C 33) Carbon dioxide crosses the plasma membrane by simple diffusion. The rate at which carbon dioxide enters the cell is determined by the A) amount of transport protein in themembrane. B) amount of oxygen being exported from the cell. C) concentration of carbon dioxide on each side of the membrane. D) amount of carbon dioxide outside of the cell. E) amount of energy being produced by the cell. Answer: C 34) What is active transport? A) Movement of molecules into or out of a cell against a concentration gradient B) Rapid movement of molecules in a solution C) Diffusion of molecules within a cell D) Movement of molecules into or out of a cell down a concentration gradient E) Movement of molecules into or out of a cell using special proteins and not requiring an expenditure of energy Answer: A 35) When substances move across a plasma membrane and down concentration gradients, this is called A) exocytosis. B) pinocytosis. C) passive transport. D) active transport. Answer: C 36) To say that a cell is "selectively permeable" means A) it is permeable to different substances than other cells. B) sometimes water passes through, and sometimes it can't. C) it has different-sized perforations in the membrane. D) permeability depends on gradient differences. E) only certain molecules can pass through. Answer: E

37) What happens when diffusion moves molecules across the plasma membrane? A) Energy input is required to transport molecules. B) The rate of diffusion cannot be influenced by the cell. C) The cell gains needed materials and gets rid of excess materials very quickly. D) Most molecules are capable of crossing the phospholipid bilayer at any location and at basically the same rate. E) The process is relatively slow and is driven by concentration gradients. Answer: E 38) All of the following may influence the rate of simple diffusion across a selectively permeable membrane EXCEPT the A) size of the molecule. B) temperature. C) lipid solubility of the molecule. D) concentration gradient. E) size of the cell. Answer: E 39) Molecules that permeate a plasma membrane by facilitated diffusion A) require energy. B) require the aid of transport proteins. C) do so much more quickly than those crossing by simple diffusion. D) move from an area of low concentration to an area of high concentration. Answer: B 40) Which of the following occurs as an enzyme produced by a cell is secreted from the cell? A) Exocytosis B) Pinocytosis C) Receptor-mediated endocytosis D) Endocytosis E) Phagocytosis Answer: A 41) Molecules assisted by carrier proteins may cross a selectively permeable membrane by A) simple diffusion. B) facilitated diffusion. C) endocytosis. D) osmosis. E) active transport. Answer: B 42) The diffusion of water molecules across a selectively permeable membrane is called A) osmosis. B) active transport. C) exocytosis. D) facilitated diffusion. E) hydrolysis. Answer: A

43) If red blood cells are taken from the body and placed in a hypertonic solution, what happens to the cells? A) The cells shrivel up because water leaves them. B) The cells remain unchanged due to equal solute concentrations inside and outside the cells. C) The cells swell and burst because water moves into them. D) They become white blood cells. E) The cells remain unchanged due to equal water concentrations inside and outside the cells. Answer: A 44) Imagine an artificial cell made with a selectively permeable membrane that allows water to pass through but does not allow sugar to pass. If the artificial cell contains a 1% sugar solution and then you place the cell in a 2% sugar solution, what happens? A) Water leaves the cell because the solution is hypertonic to the cell. B) Sugar diffuses in and water diffuses out until equilibrium is reached. C) There is no movement ofwater. D) Water enters the cell because the solution is hypotonic to the cell. Answer: A 45) A freshwater protozoan, such as Paramecium, tends to A) gain water; isotonic B) gain water; hypotonic C) lose water; hypertonic D) gain water; hypertonic E) lose water; hypotonic

because it livesin a

environment.

Answer: B 46) Solutions that cause water to enter cells by osmosis are called A) hypotonic. B) hypertonic. C) isotonic. D) permeable. E) hydrophilic. Answer: A 47) The blood plasma of a man who drinks salt water will become blood cells will be to the blood plasma. A) hypotonic; hypertonic B) isotonic; isotonic C) hypertonic; hypotonic D) isotonic; hypertonic E) hypertonic; isotonic Answer: C 48) The slowest rate of diffusion of dye particles in water will occur at A) 60°C. B) 10°C. C) 30°C. D) 20°C. Answer: B

to his red blood cells, whereas the red

49) Suppose you have two glucose solutions separated by a selectively permeable membrane. If there is a concentration gradient of glucose across the membrane, then the solutions cannot be relative to each other. A) isotonic B) hypertonic C) hypotonic Answer: A 50) Imagine that beaker A has a 10% sucrose solution, and beaker B has an 8% sucrose solution. This means that A) beaker A is hypotonic relative to beaker B. B) beaker A is hypertonic relative to beaker B. C) beaker A is isotonic relative to beaker B. Answer: B 51) More than half a century ago, two cell biologists published details of their research involving isolated membrane vesicles from chloroplasts. Normally, the fluid inside these vesicles is near neutral. In an experiment, these membrane vesicles were soaked in an acidic solution (pH 4) until the inside of the vesicle also became pH 4. Based on the details provided in this scenario, by what mechanism could hydrogen ions have crossed the vesicle membrane, and what do you think happened at the molecular level? A) Osmosis; water moved from inside the vesicle to outside. B) Pinocytosis; water moved from outside the vesicle to inside. C) Facilitated diffusion; hydrogen ions moved into the vesicle through a channel protein. D) Active transport; hydrogen ions moved out of the vesicle with the help of ATP energy. E) Simple diffusion; hydrogen ions moved into the vesicle through a channel protein. Answer: C 52) The secretion of excess water via a contractile vesicle of a Paramecium cell is an example of A) osmosis. B) active transport. C) exocytosis. D) simple diffusion. E) facilitated diffusion. Answer: C 53) Two aqueous solutions are separated by a selectively permeable membrane that allows water to pass through but does not allow starch to pass through. Solution A is 10% starch and solution B is 5% starch. What will occur? A) Starch will diffuse from solution A to solution B. B) Water will diffuse from solution A to solution B. C) Both water and starch will diffuse from solution B to solution A. D) Water will diffuse from solution B to solution A. E) Starch will diffuse from solution B to solution A. Answer: D

54) The rate of facilitated diffusion of a molecule across a membrane will increase as the concentration gradient of the molecule across the membrane increases to a certain point. Eventually, an increase in the concentration of the molecule will not cause any further increase in facilitated diffusion. Thus, there is a maximal rate of facilitated diffusion. This isbecause A) the increased concentration gradient causes a situation far from equilibrium. B) there are a limited number of carrier proteins in the membrane. C) facilitated diffusion requires ATP energy. D) as the concentration gradient increases, molecules interfere with one another. E) the diffusion constant depends on the concentration gradient. Answer: B 55) Osmosis moves water from a region of A) high solute concentration to a region of low solute concentration. B) hypertonic solution to a region of hypotonic solution. C) negative osmotic potential to a region of positive osmotic potential. D) low concentration of water to a region of high concentration of water. E) low solute concentration of to a region of high solute concentration. Answer: E 56) Glucose is a six-carbon sugar that diffuses slowly through artificial phospholipid bilayers. The cells lining the small intestine, however, rapidly move large quantities of glucose from the glucose-rich food into their glucosepoor cytoplasm. Given this information, which transport mechanism is most probably functioning in the intestinal cells? A) Osmosis B) Exocytosis C) Simple diffusion D) Aquaporin transport E) Facilitated diffusion Answer: E 57) Two similar-sized animal cells are placed in a 0.5% sucrose solution. Cell A enlarges for a while and then stops; cell B continues to enlarge and finally ruptures. Which of the following must have been TRUE at the beginning of the experiment? A) Cell B has a higher concentration of sucrose than cell A. B) Cell A has a higher concentration of sucrose than cell B. C) Cell A was hypertonic to the solution, and cell B was hypotonic. D) Cell A was hypotonic to the solution, and cell B was hypertonic. E) Cells A and B were isotonic to each other. Answer: A 58) The cytoplasm of a certain cell, such as a neuron, already has a high concentration of K+ ions. How can K+ ions continue to enter the cell? A) Infusion B) Active transport C) Exocytosis D) Facilitated diffusion E) Osmosis Answer: B

59) The gases O2 and CO2 enter or leave a plant cell by A) facilitated transport. B) active transport. C) simple diffusion. D) osmosis. E) facilitated diffusion. Answer: C 60) Active transport requires all of the following EXCEPT A) ATP. B) transport proteins. C) aquaporins. D) a membrane. E) a gradient. Answer: C 61) The process in which white blood cells engulf bacteria is termed A) pinocytosis. B) recognition. C) phagocytosis. D) reception. E) exocytosis. Answer: C 62) Which process accounts for the movement of solid particles (such as food) into some animal cells? A) Facilitated diffusion B) Osmosis C) Phagocytosis D) Simple diffusion E) Active transport Answer: C 63) Cells use exocytosis to A) pump hydrogen molecules across themembrane. B) release substances from the cell. C) move away from danger. D) create new cells. E) ingest nutrients. Answer: B 64) If you forget to water your favorite plant, all of the following will occur at a cellular level EXCEPT A) the plasma membrane will shrink away from the cell wall. B) osmosis will occur. C) turgor pressure will build up in the cell. D) water will move out of the vacuoles by osmosis. E) water will move out of the cytosol by osmosis. Answer: C

65) If a frog egg cell is placed into a hypotonic solution, it will A) swell via osmosis. B) swell via facilitated diffusion. C) shrivel via osmosis. D) shrivel via facilitated diffusion. E) shrivel via activetransport. Answer: A 66) Which of the following requires adenosine triphosphate? A) Active transport B) Simple diffusion C) Facilitated diffusion D) Osmosis Answer: A 67) Specialized cell junctions include all of the following EXCEPT A) desmosomes. B) tight junctions. C) gap junctions. D) phospholipases. Answer: D 68) The electrical signal for a muscle to contract passes rapidly from one cell to the next via A) plasmodesmata. B) tight junctions. C) gap junctions. D) desmosomes. E) internal proteins. Answer: C 69) Adhesion of cells within animal tissues is accomplished by cell-to-cell junctions called A) desmosomes. B) tight junctions. C) gap junctions. D) plasmodesmata. Answer: A 70) The urinary bladder is protected from leaking by cell-to-cell junctions called A) desmosomes. B) tight junctions. C) gap junctions. D) plasmodesmata. Answer: B 71) Protein channels that provide passage for hormones and nutrients between animal cells are termed A) desmosomes. B) tight junctions. C) gap junctions. D) plasmodesmata. Answer: C

72) You observe a cell under a microscope and you can clearly see a cell wall, a vacuole, and cytoplasmic connections. These cytoplasmic connections must be A) gap junctions. B) plasmodesmata. C) tight junctions. D) osmotic channels. E) desmosomes. Answer: B 73) Carrier molecules in the plasma membrane are required only for active transport. A) True B) False Answer: B 74) Osmosis is the diffusion of water molecules across selectively permeable membranes. A) True B) False Answer: A 75) After a dye diffuses uniformly throughout a glass of water, the dye molecules are no longer moving. A) True B) False Answer: B SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 76) The most common lipids in biological membranes are

Answer: phospholipids 77) Phospholipids contain two different parts: a

head and a pair of

tails.

Answer: polar and/or hydrophilic; nonpolar and/or hydrophobic 78) The movement of molecules across a cell membrane via a transport protein in which no energy is required is called diffusion, and the movement of molecules across a cell membrane via a protein in which energy (i.e., ATP) is required is called transport. Answer: facilitated; active 79) Facilitated diffusion and active transport both require membrane.

for the movement of molecules across the

Answer: transport proteins 80)

is used by white blood cells to consume large particles such as bacteria. Answer: Phagocytosis

81) Communication between cells occurs via

in plant cells and via

in animal cells.

Answer: plasmodesmata; gap junctions 82) The cells of the bladder are joined to one another by cells of this tissue. Answer: tight junctions

that prevent substances from passing between the

83) The antibiotic polymyxin B attaches itself to the phospholipids in the phospholipid bilayer and increases the permeability of the membrane. Describe what will occur as a result. Answer: The plasma membrane will lose its ability to be a selectively permeable barrier. Substances will leak out of the cell, and some previously excluded substances may enter. Eventually, the cell will die. 84) How does the cell membrane act as a "gatekeeper" for the cell? Answer: It separates the internal and external cell environments, it regulates the exchange of substances between the external environment and the cytoplasm, and it allows for communication between cells. 85) Compare and contrast facilitated diffusion and active transport. Answer: Both require membrane transport proteins. However, facilitated diffusion does not require energy and moves substances down a concentration gradient. Active transport requires energy and moves substances against a concentration gradient. 86) Compare and contrast osmosis and simple diffusion. Answer: Both are passive processes. However, osmosis refers to the movement of water down its concentration gradient across a selectively permeable membrane. No membrane or membrane protein is required for simple diffusion. 87) Why is the biological membrane said to be selectively permeable? Answer: It allows only some molecules to pass through while barring others. 88) Suppose a bag made of a selectively permeable membrane was filled with a 5% solution of glucose and sealed. What would happen if the bag was placed in pure water or in a 10% glucose solution? Answer: In pure water, the bag would swell as water moves in. In the glucose solution, the bag would shrink as water moves out. 89) Why does the cell perform endocytosis in addition to active and passive transport? Answer: Endocytosis is required for the transport of proteins, microbes, extracellular fluid, and specific molecules that are all larger than the molecule size transported by active and passive transport. 90) Distinguish among the three types of endocytosis: pinocytosis, receptor-mediated endocytosis, and phagocytosis. Answer: Pinocytosis is for fluid intake, receptor-mediated endocytosis is for the uptake of specific molecules, and phagocytosis is used to move large particles into the cell. 91) Both plant cells and animal cells will swell if placed in a hypotonic solution. However, only the animal cell will burst. Why? Answer: Water will enter both cells due to osmosis. In the animal cell, water will continue to enter as long as the extracellular solution is hypotonic, causing the pliable animal cell membrane to eventually break and the cell to burst. The stiff cell wall found in plant cells but not animal cells will not expand indefinitely. At some point, as the cytoplasm of the plant cell expands, the cell wall will exert a back pressure on the cell. Further water uptake will be prevented and the plant cell will not burst. 92) When very small viruses infect a plant cell by crossing its membrane, the viruses often spread rapidly throughout the entire plant without crossing additional membranes. Explain how this occurs. Answer: The viruses travel cell to cell via the plasmodesmata junctions.

93) Compare and contrast the intercellular junctions that allow communication between plant and animal cells. Answer: Gap junctions in animal cells and plasmodesmata in plant cells are both involved in coordinating the actions of adjacent cells. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 94) Based on these four illustrations of diffusion, which mode would most likely be used to transport oxidized zinc (which has a charge of +2) through the cell membrane?

A) Simple diffusion through the bilayer B) Osmosis through aquaporins C) Facilitated diffusion through carrier proteins D) Facilitated diffusion through channel proteins Answer: D 95) If the radius of one cell were twice as large as the radius of another cell, how much higher or lower would its surface-area-to-volume ratio be?

A) 2 timeslower B) 2 times higher C) 10 times higher D) 1/2 lower Answer: D

96) Cystic fibrosis is a genetic disease that leads to the production of excessive, thick mucus in the respiratory tract, causing frequent and serious respiratory infections. The defect is due to the production of a faulty membrane protein for the transport of the chloride ion. The protein exists in membranes, but it doesn't function normally. Based on this scenario, what is occurring at the molecular level in a person with cystic fibrosis? A) A carrier protein is being adversely affected. B) A receptor protein is being adversely affected. C) Protein filaments in the cytoplasm are being adversely affected. D) A recognition protein is being adversely affected. E) A channel protein is being adversely affected. Answer: E

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Which of the following has the greatest amount of kinetic energy? A) A tank of gasoline B) An unlit firecracker C) The cool air surrounding the car engine D) A moving car E) A hot carengine Answer: D 2) Which of the following does NOT have much potential energy? A) A diver on a springboard B) A glucose molecule C) A water droplet at the top of a waterfall D) A ball that has rolled downhill and stopped E) A 9-volt battery Answer: D 3) All of the following statements are true of the first law of thermodynamics EXCEPT A) the first law of thermodynamics is often called the law of the conservation of energy. B) the total amount of energy within a closed system remains the same. C) one form of energy may be converted to a different form of energy. D) the amount of useful energy decreases when energy is converted from one form to another. Answer: D 4) In an isolated system, all of the following are true of the second law of thermodynamics EXCEPT A) reactions cause energy to be converted from more useful to less useful forms. B) there is a natural tendency toward greater disorder in the organization of matter (increase in entropy). C) all chemical reactions release more energy than they consume. D) the amount of useful energy decreases. Answer: C 5) Entropy is a measure of an increase in A) kinetic energy. B) randomness. C) potential energy. D) high-level energy. E) organization. Answer: B 6) How is your body able to work against the effects of entropy? A) Eating a balanced diet and proper nourishment B) Regular work C) Regular exercise D) Sunbathing Answer: A

7) Each of the following requires 12 carbon atoms. Which of the arrangements of carbon atoms has the greatest entropy? A) 1 molecule of the disaccharide maltose, C12H22O11 B) 12 molecules of carbon dioxide, CO2 C) 4 molecules of the monosaccharide pyruvate, C3H4O3 D) 2 molecules of the monosaccharide glucose, C6H12O6 Answer: B 8) Energy that is not converted to useful energy is usually given off as A) light. B) electricity. C) heat. D) radioactivity. E) entropy. Answer: C 9) During photosynthesis, plants convert light energy to chemical energy. This is an example of A) a spontaneous reaction. B) increasing entropy. C) chemical equilibrium. D) the second law of thermodynamics. E) the first law of thermodynamics. Answer: E 10) Similar to a car, a human body is about A) 1% B) 95% C) 75% D) 25%

efficient in converting chemical energy to movement.

Answer: D 11) Which of the following is part of the first law of thermodynamics? A) Kinetic energy is stored energy. B) Energy cannot be created or destroyed. C) Exergonic reactions are coupled with endergonic reactions. D) Potential energy equals kinetic energy in a reaction. E) Energy cannot be transferred or transformed. Answer: B 12) How is it possible for living organisms to comply with the second law of thermodynamics? A) Chemical reactions inside cells mostly cause an increase in high-level energy. B) Living organisms are totally isolated systems that are not subject to the laws of physics. C) Organisms are able to function efficiently on heat energy alone. D) Living organisms are unique in that they do not require energy for survival. E) Sunlight functions as an ultimate source of energy for most forms of life on Earth. Answer: E

13) What is the ultimate source of energy for almost all forms of life on Earth? A) Thermal energy B) Chemical energy C) Solar energy D) Nuclear energy E) Heat energy Answer: C 14) In exergonic chemical reactions, A) energy is stored by the reactions. B) the reactants have more energy than do the products. C) the reactants and products have equal amounts of energy. D) the reactants have less energy than do the products. Answer: B 15) When solid sodium hydroxide is added to water, the solution gets hot. This is an example of a(n) A) release of activation energy. B) exergonic process. C) endergonic process. D) enzyme-catalyzed process. E) conversion of kinetic energy to potential energy. Answer: B 16) Why is photosynthesis considered an endergonic reaction? A) Sugar has less energy than does the sun. B) Low-energy reactants are converted to high-energy products. C) Photosynthesis does not comply with the physical laws of the universe. D) Activation energy is not required. E) Protein catalysts are not needed. Answer: B 17) Activation energy is necessary for all A) endergonic B) chemical C) exergonic D) coupled

reactions.

Answer: B 18) When, if ever, do molecules stop moving? A) At absolute zero (-273.15°C) B) At the freezing point (0°C) C) At the boiling point (100°C) D) Never Answer: A

19) A(n) chemical reaction releases energy, whereas a(n) A) exergonic; endergonic B) enzymatic; endergonic C) endergonic; enzymatic D) equilibrium; exergonic E) endergonic; exergonic

reaction requires an input ofenergy.

Answer: A 20) In the liver, the polysaccharide glycogen is broken down into glucose monomers. The glucose molecules are then released into the blood when blood sugar levels need to be raised. This process is an example of a(n) reaction. A) exergonic B) kinetic C) endergonic D) potential Answer: A 21) Imagine that you are conducting an experiment on a yeast enzyme known as sucrase. This enzyme is used by yeast cells to break down the disaccharide sucrose into the monosaccharides glucose and fructose. What type of reaction is this? A) Endergonic B) Spontaneous C) Exergonic D) Metergonic Answer: C 22) Which of the following is the best description of a coupled reaction? A) Reactions that occur during sexualreproduction B) Two reactions that occur simultaneously C) Two reactions that occur in the same organelle D) Two reactions, where the product of the first reaction is the reactant of the second reaction E) A reaction that occurs right after another reaction Answer: D 23) Why is photosynthesis a coupledreaction? A) An exergonic reaction occurs in the sunlight, and an endergonic reaction occurs in the plant. B) The exergonic reaction occurs in the plant, and the endergonic reaction occurs in the soil. C) Sunlight energy enters a plant and is ultimately lost as heat. D) The exergonic reaction occurs in the plant, and the endergonic reaction occurs in the sunlight. E) Photosynthesis requires two reactants: carbon dioxide and water. Answer: A 24) The most common energy carrier molecule in living organisms is A) ATP. B) glucose. C) NADPH. D) ADP. E) DNA. Answer: A

25) A "high-energy" bond in an ATP molecule is located between A) ribose and the first phosphategroup. B) two phosphate groups. C) adenine and ribose. D) adenine and the first phosphate group. Answer: B 26) When a muscle cell demands energy to perform its work of contraction, ATP A) manufactures more ATP. B) is phosphorylated. C) catalyzes the reaction. D) enters a metabolic pathway. E) is broken down and liberates energy. Answer: E 27) Which of the following is NOT a commonly used energy carrier in the cell? A) FAD B) NAD C) H2O D) ATP Answer: C 28) When a high-energy bond in ATP is broken, what primarily happens to the released energy? A) It provides the energy needed to drive endergonic reactions in the cell. B) It polarizes the cell. C) It functions as a second messenger. D) It is lost aslight energy. E) It converts inorganic phosphates to energy-carrier molecules. Answer: A 29) Which molecule stores energy for just a short period of time? A) Steroids B) Phospholipids C) ATP D) Glycogen E) Protein Answer: C 30) ATP is an energy carrier. Where is the energy actually located? A) Inside the phosphate B) Attached to the nucleotide C) Between the sugar and thephosphate D) In the bonds between phosphategroups E) Attached to the phosphate group Answer: D

31) FADH2 is an example of a(n) A) enzyme. B) active site. C) protein. D) enzyme-substrate complex. E) electron carrier molecule. Answer: E 32) Most reactions in the body occur too slowly to sustain life. This is because A) many reactions require large inputs of activation energy. B) there is not enough ATP in body cells. C) most biological catalysts are not active at body temperature (37°C). D) all reactions in the body are endergonic. E) no catalysts are present in body cells. Answer: A 33) Which of the following lowers the activation energy of a biochemical reaction? A) Altering pH to 7 B) Presence of a catalyst C) Low concentration of reactants D) High temperature E) High concentration ofproducts Answer: B 34) All of the following statements about catalysts are true EXCEPT A) catalysts increase the reaction rate. B) catalysts are not permanently altered during reaction. C) biological catalysts are specific enzymes. D) catalysts can be used repeatedly. E) catalysts increase activation energy requirements. Answer: E 35) The reactant in an enzyme-catalyzed reaction is the A) product. B) allosteric inhibitor. C) activation energy. D) substrate. E) active site. Answer: D 36) Enzymes are important because they A) allow reactions to occur at body temperature. B) can enable organisms to evade the laws of thermodynamics. C) are structural proteins that make up bodily tissues. D) increase the body temperature oforganisms. E) bind irreversibly tosubstrates. Answer: A

37) Place these steps of enzyme catalysis in the correct order: 1. The substrate and enzyme changeshape. 2. The substrate enters the activesite. 3. The enzyme reverts to its original configuration. 4. The product is expelled. A) 2, 3, 1, 4 B) 1, 3, 4, 2 C) 2, 1, 4, 3 D) 1, 2, 3, 4 E) 2, 1, 3, 4 Answer: C 38) Which of the following statements regarding enzymes is FALSE? A) Enzymes provide energy for the reactions they catalyze. B) An enzyme may be used many times for the same specific reaction. C) The activity of enzymes can be regulated by factors in their environment. D) Enzymes are proteins that function as biological catalysts. E) Enzymes are highly specific for the molecules to which they attach. Answer: A 39) Which of the following functions as a biological catalyst? A) Steroid B) Amino acid C) Energy-carrier molecule D) Enzyme E) Substrate Answer: D 40) Which statement best describes the relationship between an enzyme and a reactant? A) The relationship is temporary. B) One enzyme typically has many reactants with which it will associate. C) Covalent chemical bonds stabilize therelationship. D) The resultant product and the enzyme are permanently bonded together. E) The enzyme and the reactant molecule are both permanently changed. Answer: A 41) Animals have enzymes that break apart starch molecules but not cellulose, despite the fact that both are made up of glucose subunits. Which enzyme characteristic best explains this? A) Enzymes are not permanently changed by the reactions they promote. B) Enzyme activity is regulated. C) Enzymes usually speed up chemical reactions. D) Enzymes are highly specific. E) All enzymes are proteins. Answer: D 42) All of the following are examples of noncompetitive inhibitors EXCEPT A) nerve gas. B) arsenic. C) lead. D) mercury. Answer: A

43) To say that an enzyme has been denatured means that A) the enzyme is working at its maximal rate. B) an inhibitor has bound the enzyme at the active site. C) its three-dimensional structure has changed and the enzyme can no longer function properly. D) the enzyme is working at an optimal temperature. Answer: C 44) All of the following are ways in which enzymes are regulated by the cell EXCEPT A) a heavy metal (such as lead) may block the enzymes non-active site. B) by feedback inhibition. C) by first synthesizing the enzyme in an inactive form. D) a gene coding for the enzyme may be turned off. Answer: A 45) The hydrolysis of sucrose to glucose and fructose is a spontaneous reaction inside our bodies. However, if you dissolve sucrose in water and keep the solution overnight at room temperature, there is no detectable conversion to glucose and fructose. Why not? A) The reaction is at equilibrium. B) The reaction requires a catalyst. C) The activation energy of the reaction decreases. D) The energy of the products is higher than that of the energy of the reactants. E) The reaction is endergonic. Answer: B 46) The end product of a biosynthetic pathway often acts to block the initial step in that pathway. This phenomenon is called A) allosteric activation. B) irreversible inhibition. C) substrate activation. D) denaturation. E) feedback inhibition. Answer: E 47) Competitive and noncompetitive enzyme inhibitors differ with respect to A) their pH. B) their energies of activation. C) the temperature at which they work best. D) the precise location on the enzyme to which they bind. Answer: D 48) Which of the following will bind to the active site of an enzyme? A) Allosteric inhibitor only B) Noncompetitive inhibitor only C) Substrate only D) Both substrate and competitive inhibitor E) Competitive inhibitor only Answer: D

49) The optimum reaction rate of a particular enzyme occurs at pH 7.3 at 37°C. This reaction would probably proceed faster by A) decreasing the pH and increasing the temperature. B) increasing the pH and maintaining the temperature at 37°C. C) increasing both temperature and pH. D) increasing the temperature to 38°C and keeping the pH at 7.3. Answer: D 50) For many enzymes, the rate of product formation increases as the concentration of the substrate increases. Eventually the rate of the reaction reaches a maximum at which further increases in the concentration of the substrate have no effect. Why? A) The enzyme is no longer specific for the substrate. B) At high concentrations of substrate, the reaction is endergonic. C) At high concentrations of substrate, all of the enzyme active sites are being occupied by substrate molecules. D) At high concentrations of substrate, the activation energy of the reaction decreases. E) At high concentrations of substrate, the activation energy of the reaction increases. Answer: C 51) The addition of a competitive inhibitor slows down a particular reaction. What could be done to increase the rate of the reaction, even in the presence of the inhibitor? A) Add a coenzyme. B) Add more inhibitor. C) Allow the reaction to reachequilibrium. D) Add more substrate. E) Lower the temperature of the reaction. Answer: D 52) Sulfa antibiotics damage bacteria by affecting a certain bacterial enzyme. The sulfa antibiotic looks similar to a substrate normally required by the bacterial cells to live. The sulfa antibiotic occupies the active site of the required enzyme and blocks entry of its normal substrate. This prevents the bacteria from making nucleotides that are required for their reproduction and survival. Based on this information, the action of sulfa antibiotics is an example of A) activation energy. B) denaturing of proteins. C) competitiveinhibition. D) electron carriers. Answer: C 53) Preservatives such as citric acid are added to foods to interfere with bacterial growth. This creates an acidic pH in the food. Why does this affect the bacteria that are present? A) An acidic environment causes bacterial enzymes to fail or work less efficiently. B) An acidic environment causes the bacteria to grow more rapidly. C) An acidic environment increases the activation energy more quickly in bacteria. D) An acidic environment encourages endergonic reactions in the bacterial cells. Answer: A

54) Triclosan is a broad-spectrum antibacterial agent used in many household products. It is structurally similar to polychlorobiphenylol, a substrate that binds to the active site of the enzyme sulfotransferase. Based on these facts, you can conclude that triclosan most likely A) is a competitive inhibitor. B) acts as a noncompetitive inhibitor. C) functions as an enzyme when sulfotransferase is absent. D) lowers the activation energy of chemical reactions. Answer: A 55) The law of conservation of energy states that although the form of energy used remains the same, the total amount of energy changes. A) True B) False Answer: B 56) Energy is defined as the capacity to do work. A) True B) False Answer: A 57) Kinetic energy is like sitting at the top of a hill, and potential energy is like coasting down that hill on your bike. A) True B) False Answer: B 58) The photosynthetic reaction is considered an endergonic reaction. A) True B) False Answer: A 59) The burning of sugar is an example of an endergonic reaction, and photosynthesis is an example of an exergonic reaction. A) True B) False Answer: B 60) In cells, endergonic reactions are often coupled with exergonic reactions that store energy. A) True B) False Answer: B 61) AMP stores energy in its chemical bonds and is able to use that energy for work in the cell. A) True B) False Answer: B 62) Activation energy can be provided by the kinetic energy of moving molecules. A) True B) False Answer: A

63) The metabolism of a cell is the sum of all of its chemical reactions. A) True B) False Answer: A SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 64) The second law of thermodynamics states that the increasing.

, or disorder, of the universe is constantly

Answer: entropy 65) Energy transformations are not 100% efficient. Often, energy is released in the form of agreement with the second law of thermodynamics.

, which is in

Answer: heat 66) The energy of movement is referred to as

energy, and stored energy is referred to as

energy.

Answer: kinetic; potential 67) Sitting at the top of a slide, a child has

energy; sliding down, she is using

energy.

Answer: potential; kinetic 68) In chemicalreactions, the

are converted into products.

Answer: reactants 69) In chemical reactions,

reactions release energy and

reactions require an input of energy.

Answer: exergonic; endergonic 70) The burning of sugars as fuels for runners is an example of a(n) production of sugars during photosynthesis is an example of a(n)

chemical reaction, whereas the chemical reaction.

Answer: exergonic; endergonic 71) The molecule

is the major energy carrier in cells.

Answer: ATP 72) ATP is considered a short-term form of energy for the cell, whereas stable, long-term energy stores.

represent more

Answer: carbohydrates (sucrose, glycogen); fats 73) Special molecules such as NADH and FADH2 transport the cell.

in cells, which can then be used as energy in

Answer: electrons 74)

arebiological catalysts. Answer: Enzymes

75) The enzyme phosphoglucoisomerase catalyzes the conversion of glucose-6-phosphate to fructose-6-phosphate. The region on phosphoglucoisomerase where glucose-6-phosphate binds is called the . Answer: active site

76) Briefly describe the difference between kinetic energy and potential energy, and give an example of each. Answer: Kinetic energy is the energy of motion (examples include heat, light, electricity, a car moving), and potential energy is stored energy (examples include energy in chemical bonds, batteries, child sitting at the top of aslide). 77) Briefly explain the two laws of thermodynamics. Answer: The law of the conservation of energy states that although the form of energy changes, the total amount remains the same. The second law states that as energy changes from one form to another, the amount of useful energy decreases. 78) What is a simple definition of energy, from a biological perspective? Give some examples of how energy is used in a cell. Answer: Energy is the ability of a cell to do work. The cell uses energy to synthesize molecules, move objects, and generate heat (other examples could be used). 79) Compare endergonic and exergonic chemical reactions using an analogy from everyday life. Answer: There are many possible examples: Rolling a boulder up a hill requires an input of energy (an endergonic process), whereas the same boulder, once given a push, rolls down the hill spontaneously (an exergonic process). 80) Briefly describe how ATP acts as an energy carrier in cells. Answer: ATP stores energy in its chemical bonds and releases the energy when needed with the breaking of the third phosphate bond (forming ADP and phosphate). 81) Describe the molecular difference between ATP and ADP. Answer: Both ATP and ADP contain an adenosine and a sugar. In ATP, three phosphate groups are attached, whereas in ADP, only two phosphate groups are attached. 82) Coupled reactions are important components of human physiology. Describe an example of a coupled reaction in the human body. Answer: A coupled reaction is when an exergonic reaction provides the energy needed to drive an endergonic reaction. One example is when the chemical breakdown of sugars in the human body (exergonic reactions) is used to fuel essential endergonic reactions such as muscle contractions. 83) Explain how enzymes decrease the activation energy required for biological processes in our bodies. Answer: Enzymes decrease the activation energy by a combination of factors, including substrate orientation, formation of temporary chemical bonds, electrostatic interactions, and bond distortion. 84) Describe the biochemical properties of a biological catalyst. Answer: Catalysts (enzymes) speed up only those reactions that would occur spontaneously anyway. They are not consumed in the reaction, nor are they permanently changed after the reaction is completed. 85) Why does increasing the temperature of a chemical reaction generally increase the rate of the reaction? Answer: Increasing the temperature increases the kinetic energy of the reactants, causing the molecules to interact more frequently and with sufficient speed to overcome the activation energy of the reaction. 86) Normally, a certain enzyme has maximum activity at 37°C, but once it has been heated to 100°C and then cooled back down to 37°C, the enzyme is no longer active. Why? Answer: The enzyme's three-dimensional shape has been distorted, and the active site is no longer able to bind the appropriate substrates in thereaction. 12

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 87) This figure shows the metabolism of glucose and oxygen to CO2 and H2O. From what molecule do the carbon in CO2 and the hydrogen in H2O come from?

A) The catalyst B) Glucose C) O2 D) The product Answer: B SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 88) Which of the enzymes shown in the figure is active in the stomach of the human digestive tract?

Answer: pepsin

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 89) When certain molecules are pumped across biological membranes against a concentration gradient via active transport, ATP is used. In the cells of our bodies, for example, sugars are actively transported and metabolized within the membrane-enclosed mitochondria. Prokaryotes, in contrast, lack mitochondria but are nonetheless able to metabolize the same sugars. Based on the details provided in this scenario, which of the following statements is expected to be TRUE? A) Sugar metabolism in prokaryotes is exergonic, whereas in eukaryotes it is endergonic. B) The sugar-digesting enzymes in eukaryotic cells, such as sucrase, are not the same sugar-digesting enzymes found in prokaryotic cells. C) Prokaryotes and eukaryotes should have the same metabolic efficiency when digesting the same sugars, assuming their enzymes are the same. D) Overall, prokaryotes will gain more ATP per sugar molecule metabolized than will eukaryotes. Answer: D 90) Imagine that you are conducting an experiment on an enzyme known as sucrase. This enzyme is synthesized and used by yeast cells to break down the disaccharide sucrose (table sugar) into the monosaccharides glucose and fructose. You decide to conduct an experiment to test whether the sucrase enzyme can break down the artificial sweetener sucralose. Sucralose (a "chlorinated" carbohydrate) has some chemical similarity to sucrose, but is different in that three of its hydroxyl groups are missing and replaced with chlorine atoms instead. Based on the details provided in this scenario, do you think the sucrase enzyme will be able to interact with sucralose? A) No; sucralose is an ion and not a true carbohydrate. B) No; all enzymes are highly specific and can react with only a specific substrate. C) Yes; enzymes such as sucrase are not specific for their substrate. D) Yes; the enzymes in human cells can interact with artificial sweeteners as if they were sugars. Answer: B

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Before photosynthesis evolved, A) H2O B) N2 C) CO2 D) air E) O2

was rare in Earth's atmosphere.

Answer: E 2) The products of photosynthesis are A) glucose and water. B) glucose and carbon dioxide. C) carbon dioxide, water, and energy. D) carbon dioxide, chlorophyll, and oxygen. E) glucose, water, and oxygen. Answer: E 3) What structural feature of a leaf enables it to obtain CO2 from the air? A) Chloroplast B) Cuticle C) Epidermis D) Stomata E) Mesophyll Answer: D 4) The vast majority of chloroplasts found in a leaf are in the A) stroma. B) epidermis. C) mesophyll. D) vascular bundles. E) cuticle. Answer: C 5) Specifically, molecules of chlorophyll are located in the membranes of sacs called A) grana. B) stroma. C) thylakoids. D) vesicles. E) stoma. Answer: C 6) All of the following factors influence the rate of photosynthesis EXCEPT A) light intensity. B) atmospheric CO2 levels. C) water availability. D) temperature. E) atmospheric N2 levels. Answer: E

7) All of the following compounds are necessary components for photosynthesis EXCEPT A) carbon dioxide. B) oxygen. C) water. D) ATP. E) NADP. Answer: B 8) The cellular organelle that utilizes sunlight to convert carbon dioxide and water into sugar and oxygen is the A) chloroplast. B) mitochondrion. C) thylakoid. D) cristae. E) endoplasmic reticulum. Answer: A 9) Imagine that a scientist discovers a mutant plant seedling that appears to lack stomata. What would be the effect of this? A) Glucose would not be able to enter the plant as a reactant for photosynthesis. B) CO2 would not be able to enter the plant as a reactant for photosynthesis. C) Visible wavelengths of light would be unable to reach the chloroplasts. D) Additional ATP would be produced by the seedling, and the plant would grow taller. Answer: B 10) Imagine that a plant in your garden doesn't receive an adequate amount of water. Which of the following would be most affected by this? A) Both the light reactions and the Calvin cycle of photosynthesis B) The Calvin cycle of photosynthesis only C) The light reactions of photosynthesisonly D) Neither the light reactions nor the Calvin cycle of photosynthesis Answer: A 11) Albino corn has no chlorophyll. You would expect albino corn seedlings to A) use accessory pigments such as carotenoids to capture light. B) synthesize glucose indefinitely, using stored ATP and NADPH. C) capture light energy in the white end of the visible light spectrum. D) fail to thrive because they cannot capture light energy. E) switch from the C4 pathway to the crassulacean acid metabolism (CAM) pathway. Answer: D 12) The energy required for photosynthesis to occur is A) glucose. B) ultraviolet light. C) oxygen. D) visible light. E) air. Answer: D

13) In the chloroplast, energy in sunlight is passed around different chlorophyll molecules until it reaches a specific chlorophyll molecule that can transfer energy in sunlight to an energized electron. This chlorophyll molecule is called the A) electron-carrier molecule. B) reaction center. C) photoelectricpoint. D) accessory pigment. E) nucleus. Answer: B 14) Carotenoid pigments are found inthe A) nucleus. B) mitochondria. C) stroma of the chloroplasts. D) thylakoid membranes of the chloroplasts. Answer: D 15) Pigments that absorb light energy to drive photosynthesis include A) chlorophyll and carotenoids. B) chlorophyllonly. C) carotenoids only. D) carotenoids and anthocyanins. E) anthocyanins only. Answer: A 16) A pigment that absorbs red and blue light and reflects green light is A) carotenoid. B) phycocyanin. C) melanin. D) xanthophyll. E) chlorophyll. Answer: E 17) Which of the following is NOT true of chlorophyll? A) It is found in the thylakoid membrane. B) It absorbs light at the red and blue ends of the spectrum. C) It reflects green wavelengthsof light. D) It is found in mitochondria. E) It is the main photosynthetic pigment in plants. Answer: D 18) Suppose that you are experimenting with different types of lighting for your indoor green plants. Which of the following colors of light will be most effective? A) Red and green B) Black C) Orange and yellow D) Red and blue E) Green Answer: D 3

19) Which of the following statements is TRUE regarding the light reactions? A) Without photosystem I, photosystem II could not occur. B) They rely on energy provided by glucose synthesis. C) ATP and NADPH are needed. D) Without water, the system would shut down. E) Oxygen is required. Answer: D 20) The replacement electrons for the reaction center of photosystem II come from A) H2O. B) glucose. C) O2. D) photosystem I. E) NADPH. Answer: A 21) Which sequence accurately describes the flow of electrons in photosynthesis? A) Photosystem II → photosystem I → NADP → H2O B) Photosystem I → photosystem II → H2O → NADP C) Photosystem I → photosystem II → NADP → H2O D) H2O → photosystem I → photosystem II → NADP E) H2O → photosystem II → photosystem I → NADP Answer: E 22) The ATP and NADPH synthesized during the light reactions are A) dissolved in the cytoplasm. B) moved to the stroma. C) transported into the nucleus. D) pumped into a compartment within the thylakoid membrane. E) transported to the mitochondria. Answer: B 23) What is produced in the electron transport system associated with photosystem II? A) O2 B) Glucose C) ATP D) CO2 E) NADPH Answer: C 24) Light reactions produce A) glucose, ATP, and O2. B) ATP, NADPH, and H2O. C) glucose, ATP, and CO2. D) ATP, NADPH, and O2. E) ATP, NADPH, and CO2. Answer: D

25) From where does the O2 released during the light reactions of photosynthesis come? A) RuBP B) H2O C) C6H12O6 D) ATP E) CO2 Answer: B 26) During the process of photosynthesis, solar energy is converted to A) mechanical energy. B) nuclear energy. C) thermal energy. D) chemical energy. E) heat energy. Answer: D 27) The light reactions of photosynthesis result in which of the following? A) Oxidation of glucose B) Production of ATP C) Reduction of H2O D) Oxidation of CO2 E) Oxidation of chlorophyll Answer: B 28) The role of water in photosynthesis is to A) provide H2. B) provide electrons. C) maintain turgor pressure. D) provide oxygen. Answer: B 29) Which of the following is a source of electrons that plants use for reduction reactions during photosynthesis? A) Glucose B) RuBP C) O2 D) CO2 E) H2O Answer: E 30) Hydrogen ions cross the thylakoid membranes from the stroma by A) osmosis. B) active transport. C) simple diffusion. D) synthesis. E) facilitated diffusion. Answer: B

31) The energy of the movement of electrons down a concentration gradient via electron transport within chloroplasts and mitochondria is used to generate A) glucose. B) O2. C) ATP. D) H2O. E) CO2. Answer: C 32) The energy of the movement of electrons down a concentration gradient via electron transport within the thylakoid membrane is used togenerate A) glucose. B) ATP. C) H2O. D) O2. E) CO2. Answer: B 33) Which process of photosynthesis is directly linked to the production of ATP? A) Splitting of a water molecule B) Fixing of carbon C) Synthesis of O2 D) Photosystem II E) Generation of NADPH Answer: D 34) Suppose you are studying photosynthesis in a research lab. You grow your plants in a chamber with a source of water that has a radioactively labeled oxygen atom. What photosynthetic product will be radioactive? A) Glucose B) ATP C) O2 gas D) NADPH E) CO2 gas Answer: C 35) Which of the following statements is TRUE about the light reactions? A) NADPH and ATP are both synthesized from the light reactions within photosystem I. B) ATP is the final electron acceptor. C) Photosystem II generates ATP, whereas photosystem I generates NADPH. D) Photosystem I generates ATP, whereas photosystem II generates NADPH. Answer: C 36) Which of the following statements about the light reactions of photosynthesis is FALSE? A) Chlorophyll (and other pigments) absorbs light energy, which excites electrons. B) An electron transport chain is used to create a proton gradient. C) The splitting of water molecules provides a source of electrons. D) NADPH becomes oxidized to NADP+. E) ATP is formed. Answer: D 6

37) The NADPH required for carbon dioxide fixation during the Calvin cycle is formed A) during the light reactions. B) by the reduction ofoxygen. C) in the mitochondria. D) only in C4 plants. E) by the hydrolysis of ATP. Answer: A 38) The primary function of the light reactions of photosynthesis is to A) produce energy-rich ATP and NADPH. B) use ATP to make glucose. C) convert light energy to the chemical energy of lipids. D) produce energy-rich glucose from carbon dioxide and water. E) produce NADPH used in respiration. Answer: A 39) You are carrying out an experiment on several aquatic plants in your fish tank. You decide to expose two of the plants to green light and two to blue light. You want to determine which type of light is best for the light reactions, so to reach your conclusions, you decide to record the amount of oxygen bubbles produced. Which of the following results would be expected? A) There would be more bubbles from the plants in blue light than from those in green light. B) No bubbles would be produced in either green light or blue light. C) There would be the same number of bubbles from plants in blue or green light. D) There would be more bubbles from the plants in green light than from those in blue light. Answer: A 40) Which of the following provides O2 as an end product? A) Cellular respiration B) Light reactions C) Light-independent reactions D) Glycolysis E) Synthesis Answer: B 41) What condition(s) must be met for glucose to be produced during photosynthesis? A) The products of light-dependent reactions must be available. B) NADH and FADH are available. C) The concentration of O2 must be significantly higher than that of CO2. D) Mitochondria must convert light energy to ATP. Answer: A 42) The term cycle is used to describe the Calvin cycle because A) glucose is synthesized during theprocess. B) CO2 is fixed. C) the reactions occur only once in a 24-hour period. D) the metabolic pathway begins and ends with RuBP. E) the process depends on products from the light reactions. Answer: D

43) Where is glucose synthesized duringphotosynthesis? A) Cytoplasm B) Matrix C) Thylakoids D) Membrane proteins E) Stroma Answer: E 44) What is the correct order for the reactions of the Calvin cycle? A) Synthesis of G3P, carbon fixation, regeneration of RuBP B) Carbon fixation, regeneration of RuBP, synthesis of G3P C) Regeneration of RuBP, carbon fixation, synthesis of G3P D) Carbon fixation, synthesis of G3P, regeneration of RuBP E) Synthesis of G3P, regeneration of RuBP, carbon fixation Answer: D 45) Which of the following occurs during the Calvin cycle of photosynthesis? A) Nothing occurs because the plant rests in the dark. B) Chlorophyll acts as an enzyme, but only in the dark. C) Carbon dioxide is converted to chemicals that can be used to make sugars. D) Water is converted to its most basic elements, hydrogen and water. Answer: C 46) All of the following are part of the Calvin cycle EXCEPT A) synthesis of G3P. B) carbon fixation. C) generation of ATP. D) regeneration of RuBP. Answer: C 47) What happens to CO2 when it moves into the stroma? A) The CO2 splits into C and O2. B) It is converted to water. C) It gets incorporated into the Calvin cycle and goes toward the formation of glucose. D) The CO2 becomes a by-product of cellular respiration. E) It immediately passes on to the thylakoids. Answer: C 48) In green plants, the primary function of the Calvin cycle is to A) split water and release oxygen. B) construct the building blocks of simple sugars from carbon dioxide. C) transport glucose out of thechloroplast. D) use NADPH to release carbondioxide. E) use ATP to release carbon dioxide. Answer: B

49) Glucose is made during which of the following reactions? A) The light reactions only B) The Calvin cycle only C) Both the light reactions and the Calvin cycle D) Neither the light reactions nor the Calvin cycle Answer: B 50) During photosynthesis, when is CO2 utilized? A) During the light reactions only B) During the Calvin cycle only C) During both the light reactions and the Calvin cycle D) During neither the light reactions nor the Calvin cycle Answer: B 51) NADPH is a reactant required during which of the following reactions? A) The light reactions only B) The Calvin cycle only C) Both the light reactions and the Calvin cycle D) Neither the light reactions nor the Calvin cycle Answer: B 52) Enzymes are required during which of the following reactions? A) The light reactions only B) The Calvin cycle only C) Both the light reactions and the Calvin cycle D) Neither the light reactions nor the Calvin cycle Answer: C 53) Water is required to drive which of the following reactions? A) The light reactions only B) The Calvin cycle only C) Both the light reactions and the Calvin cycle D) Neither the light reactions nor the Calvin cycle Answer: C 54) NADPH is synthesized during which of the following reactions? A) The light reactions only B) The Calvin cycle only C) Both the light reactions and the Calvin cycle D) Neither the light reactions nor the Calvin cycle Answer: A 55) In the C3 pathway, where does the carbon come from to form glucose? A) Enzymes B) Chlorophyll C) Atmospheric CO2 D) ATP and NADPH E) Water Answer: C 9

56) In the reduction of CO2 during C4 photosynthesis, which of the following initially combines with CO2? A) RuBP B) PEP C) PGA D) NADH E) PGAL Answer: B 57) Where do the reactions of a C4 pathway occur in a plant such as corn? A) Mesophyll cells only B) Bundle sheath cells only C) Mesophyll and bundle sheath cells D) Epidermal cells only E) Bundle sheath and epidermal cells Answer: C 58) In the C4 pathway, what is the source of carbon? A) Water B) NADPH C) Glucose D) Carbon dioxide E) ATP Answer: D 59) What kind of habitat does a C4-pathway plant favor? A) Totally aquatic B) Hot and dry C) Wet and cloudy D) Cool and dry E) Cool and moist Answer: B 60) Photorespiration is detrimental for a plant because A) CO2 is synthesized. B) no glucose is produced. C) O2 is required. D) RuBP is degraded. E) glucose is synthesized. Answer: B 61) Where does the C4 cycle get its name? A) Only four carbons are used in the cycle. B) PEP is a four-carbon molecule. C) The first product in the cycle has four carbons. D) Four CO2 molecules are released. E) It is a four-stepprocess. Answer: C

62) If C4 photosynthesis prevents photorespiration, why haven't all plants evolved to use the C4 pathway? A) All plants will evolve to be C4 in time. B) C4 is advantageous only in high-oxygenhabitats. C) Only some plants use C4 photosynthesis. D) C4 is not advantageous in allclimates. E) C4 produces some toxicby-products. Answer: D 63) C3 plants are adapted to conditions. A) wet; dry B) drought; rainy C) dry; wet D) temperate; cool and rainy E) high-light; low-light

environmental conditions, whereas C4 plants are adaptedto

Answer: A 64) In C3 photosynthesis, what fixes thecarbon? A) ATP B) PGAL C) PGA D) PEP E) RuBP Answer: E 65) In C4 photosynthesis, where does the carbon in newly synthesized glucose come from? A) Atmospheric CO2 B) ATP and NADPH C) Water D) Enzymes E) Chlorophyll Answer: A 66) All of the following are true of biofuels EXCEPT A) these are fuels such as methane produced from renewable biological resources such as soybeans and corn. B) demand for biofuels has placed demands on rain-forest lands. C) there is concern that using food products as a fuel source will reduce the global food supply and increase food prices. D) biofuels are the only solution to our growing need for fuels in the future. E) the goal of their use is to reduce harmful carbon dioxide emissions. Answer: D 67) The stacked grana are disk-shaped, interconnected membranous sacs embedded in the membrane of the stroma. A) True B) False Answer: A

68) The majority of the leaf's chloroplasts are found in the mesophyll cells. A) True B) False Answer: A 69) The photosystems are involved in the light reactions of photosynthesis. A) True B) False Answer: A 70) Carbon dioxide is required in the light reactions of photosynthesis. A) True B) False Answer: B 71) The carotenoids and other accessory pigments in the chloroplast help capture light into the reaction center's chlorophyll molecules. A) True B) False Answer: A 72) Under dry conditions, a C4 plant is more efficient at photosynthesis than that of a C3 plant. A) True B) False Answer: A SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 73) Light reactions occurin the mesophyll leaf cell.

, and the Calvin cycle occurs in the

of the chloroplast of a typical

Answer: thylakoids; stroma 74) The cells in the

layer of the leaf contain the majority of a leaf's chloroplasts.

Answer: mesophyll 75) The process of photosynthesis converts solar energy to

energy stored in the bonds of glucose.

Answer: chemical bond 76) Many plants have evolved leaves that have adjustable pores, called water loss.

, which allow for gas exchange and

Answer: stomata 77)

is the main light-capturing molecule in chloroplasts and is responsible for giving leaves their characteristic green color. Answer: Chlorophyll

78) In the process of photosynthesis, and Calvin cycle to reduce carbon dioxide to glucose.

formed during the light reactions are required in the

Answer: ATP; NADPH

79) During the light reactions of photosynthesis, the synthesis of

is coupled to the diffusion of protons.

Answer: ATP 80) Light-harvesting pigments in the chloroplast include chlorophyll and the yellowish accessory pigments called . Answer: carotenoids 81) A(n) system.

is composed of a light-harvesting complex of chlorophyll pigments and an electron transport

Answer: photosystem 82) Photosystem II generates light reactions.

, and photosystem I generates

, both of which are required by the

Answer: ATP; NADPH 83) During the Calvin cycle, the combination of oxygen with RuBP rather than carbon dioxide is called

Answer: photorespiration 84) Some plants, called the

plants, have evolved a way to reduce photorespiration.

Answer: C4 85) During the process of

, RuBP combines with oxygen instead of carbon dioxide.

Answer: photorespiration 86) In C3 plants, the Calvin cycle occurs in the chloroplasts of occurs in the cells.

cells, but in C4 plants, the Calvin cycle

Answer: mesophyll; bundle sheath 87) Give the simplest chemical equation for photosynthesis. For each reactant, indicate where the plant acquires it. For each product, note during what part of photosynthesis it is produced. Answer: The chemical equation for photosynthesis is 6 CO2 + 6 H2O + light energy → C6H12O6 + 6 O2 CO2 comes through the stomata, water comes from the vascular bundles (or veins) to the mesophyll cells, and chlorophyll molecules embedded in the thylakoid membrane of the chloroplast absorb sunlight. The glucose is produced immediately following the Calvin cycle, and the oxygen is produced during the light reactions. 88) Explain how the leaf is adapted for capturing energy from sunlight and for acquiring carbon dioxide and water. Answer: CO2 comes through adjustable pores, or stomata, and water comes from the vascular bundles (or veins) to the mesophyll cells. Leaves are broad and flat to provide a large surface area to the sun. Chlorophyll molecules embedded in the thylakoid membrane of the chloroplast absorb sunlight. 89) What is the role of the green pigment chlorophyll in photosynthesis? Answer: Chlorophyll is critical in light reactions to harness light energy and begin the flow of electrons, which in turn creates the proton gradient allowing for ATP formation, which is required for the Calvin cycle.

90) Describe the two major components of a photosystem. What is the function of each? Answer: The light-harvesting complex absorbs light and passes the energy to a specific chlorophyll molecule called the reaction center. The electron transport system is a series of electron-carrier molecules that are responsible for directly donating electrons to the electron carrier molecule NADP+ and indirectly driving the synthesis of ATP. 91) Imagine you are conducting a photosynthesis experiment on a plant in the lab. You block any light from reaching the plant. Explain the specific effect this will have on the light reactions. Answer: Light will not be present to hit the chlorophyll and electrons will not be excited. Therefore, the light reactions will not occur and no energy will be produced to be used in the Calvin cycle. 92) Is glucose a direct product of the Calvin cycle? Explain. Answer: No; G3P is the carbohydrate produced, and two of these molecules must combine to form one molecule of glucose. 93) Which component of the Calvin cycle is recycled, and why is this important for the Calvin cycle? Answer: The RuBP molecule is recycled. This is essential to maintain the cyclical nature of the process. 94) How are the light reactions and the Calvin cycle related to each other? Answer: The light reactions produce the ATP and NADPH required to drive the Calvin cycle, which results in the synthesis of sugar (glucose). 95) What happens to the photosynthetic reactions when no sunlight is present? Answer: ATP and NADPH levels from the light reactions become limiting, and that in turn can lead to a decrease in sugar production following the Calvin cycle. 96) Why does photorespiration reduce photosynthesis efficiency? Answer: Photorespiration does not produce any useful cellular energy, and it prevents the synthesis of glucose in C3 plants. 97) What is photorespiration? Describe how C4 plants have evolved the ability to reduce photorespiration. Answer: Photorespiration occurs when RuBP combines with O2 rather than CO2, so the plant is not allowed to fix carbon and produce glucose. C4 plants use a two-stage carbon-fixation pathway where PEP is used instead of RuBP, which specifically reacts with CO2 and not O2. The CO2 is then shuttled to the bundle sheath cells and creates a high CO2 concentration that favors the regular C3 cycle reactions without competition from O2.

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 98) Based on the information provided in this figure, where does the oxygen gas produced by a leaf come from?

A) NADPH B) C6H12O6 C) H2O D) CO2 Answer: C 99) Based on this graph, which wavelengths of light would result in the highest rates of ATP production during photosynthesis?

A) 700-750 nanometers B) 600-650 nanometers C) 550-600 nanometers D) 450-500 nanometers Answer: D 15

100) Based on the information provided in this figure, what event contributes directly to the creation of a proton gradient across the thylakoid membrane?

A) The creation of ATP B) The splitting of H2O C) The creation of C6H12O6 D) The flow of electrons through electron transport chain II E) The flow of electrons through photosystem I Answer: D SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 101) Imagine that, similar to events that occurred 65 million years ago, a huge meteorite were to hit Earth tomorrow, spewing cloudy debris into the atmosphere and blocking a large proportion of sunlight. Because plants rely on sunlight, global rates of photosynthesis would be greatly reduced, and many of the animals that depend on photosynthetic plants (such as herbivores and the predators that feed on those herbivores) would starve or go extinct. In this scenario, why can't the plants continue to produce sugars and survive if the sugar-producing reactions in photosynthesis are considered 'light independent"? Answer: The Calvin cycle, used to drive the synthesis of glucose, requires ATP and NADPH produced during the light reactions.

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 102) Consider the scenario of two scientists conducting an experiment to track what happens to the carbon atoms from CO2 molecules used during the Calvin cycle of photosynthesis. They add a radioactive "tag" to the carbon atoms of the CO2 reactants and then collect the products following the reactions. They analyze the products for their level of radioactivity. Which product(s) would you expect to be radioactive? A) Both water and glucose B) Glucose only C) Both ATP and water D) ATP only E) Water only Answer: B

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) At the end of glycolysis, the original carbons of the glucose molecule form A) two molecules of pyruvate. B) six molecules of carbon dioxide. C) two molecules of citric acid. D) two molecules of fructose. E) two molecules of NADH. Answer: A 2) The anaerobic breakdown of glucose is called A) the Krebs cycle. B) fermentation. C) phosphorylation. D) cellular respiration. E) chemiosmosis. Answer: B 3) If glucose is metabolized under completely anaerobic conditions, pyruvate A) is converted by fermentation to lactate or CO2 + ethanol. B) immediately enters the Krebs cycle. C) is converted to NADH. D) is converted back to fructose until the concentration of oxygen increases. E) leaves the fluid portion of the cytoplasm and enters the mitochondrial matrix. Answer: A 4) All of the following are true statements about ATP EXCEPT that it is A) the molecule that all living cells rely on to do work. B) a short-term energy-storage compound. C) the cell's principal compound for energy transfers. D) synthesized only within mitochondria. Answer: D 5) Which of the following statements is TRUE of glycolysis? A) It produces a net gain of ATP. B) It produces more ATP than does aerobic respiration. C) It produces a net gain of FADH. D) It only takes place under anaerobic conditions. E) It can be performed only by bacteria. Answer: A 6) The main function of cellular respiration is to produce A) ATP. B) glucose. C) CO2. D) NADH and FADH2. Answer: A

7) During aerobic respiration in cells, about of the chemical energy in a metabolized glucose molecule is used for ATP production and the rest is released as heat. A) more than 90% B) 40% C) less than 1% D) 25% Answer: B 8) If no oxygen is available to a cell, then the net ATP production resulting from the metabolism of a single glucose molecule is A) 2 ATP molecules. B) 36 ATP molecules. C) 32 ATP molecules. D) 1 ATP molecule. E) no ATP. Answer: A 9) Which event occurs in the fluid portion of the cytoplasm of a cell undergoing glucose metabolism? A) Krebs cycle B) Glycolysis C) Electron transport D) Chemiosmosis E) Acetyl CoAformation Answer: B 10) Where does the production of pyruvate occur during glycolysis? A) Inner membrane B) Ribosomes C) Intermembrane compartment D) Mitochondrial matrix E) Cytoplasmic fluid Answer: E 11) During glycolysis, what is the net gain of ATP molecules produced from one glucose molecule? A) 2 B) 36 C) 4 D) 34 E) No ATP molecules are produced during glycolysis. Answer: A 12) What molecule is common to both C3 photosynthesis and the process of glycolysis? A) NADPH B) G3P C) Fructose D) Acetyl CoA E) Pyruvate Answer: B

13) Which kind of metabolic poison would interfere with the glycolysis stage of cellular respiration? A) An agent that reacts with oxygen and depletes its concentration in the cell B) An agent that binds to lactate and inactivates it C) An agent that inhibits the formation of acetyl CoA D) An agent that reacts with FADH2 and oxidizes FAD+ E) An agent that closely mimics the structure of glucose but is not capable of being metabolized and broken down Answer: E 14) The end product of glycolysis is A) two citric acid molecules. B) one lactate molecule. C) one G3P molecule. D) two pyruvate molecules. E) two NAD+molecules. Answer: D 15) During glycolysis in the energy-investing stage, two ATP molecules are "spent" to convert glucose to the highly reactive molecule A) pyruvate. B) FADH2. C) glyceraldehyde 3-phosphate. D) fructose bisphosphate. E) NADH. Answer: D 16) In the glucose activation stage of glycolysis, glucose receives a phosphate group from ATP. This reaction is A) fermentation. B) exergonic. C) respiration. D) endergonic. Answer: D 17) For bacteria to continue growing rapidly when they shift from an aerobic environment to an anaerobic environment, they must A) increase the rate of glycolysis. B) produce more ATP per molecule of glucose during glycolysis. C) increase the rate of the Krebs cycle. D) produce ATP using NADH. E) increase the rate of glucose production. Answer: A 18) During the glucose activation stage of glycolysis A) there is a net gain of four ATP molecules. B) there is a conversion of two G3P molecules to two pyruvate molecules. C) there is a net gain of two ATP molecules. D) two ATP molecules are used to make one fructose bisphosphate molecule. E) fructose bisphosphate is split into two G3P molecules. Answer: D

19) The overall products of glycolysis are A) ATP and pyruvate only. B) ATP, NADH, and acetyl CoA. C) ATP, NADH, FADH2, and CO2. D) ATP, NADH, pyruvate, and FADH2. E) ATP, NADH, and pyruvate. Answer: E 20) During cellular respiration, the pyruvate produced in glycolysis is A) converted to lactate or ethanol. B) transported out of the mitochondria. C) the source of electrons for NADH and FADH2. D) broken down to O2 and hydrogen. Answer: C 21) During which step of aerobic respiration is oxygen used? A) Krebs cycle B) Conversion of pyruvate to acetyl CoA C) Electron transport chain (ETC) D) Fermentation E) Glycolysis Answer: C 22) We breathe more heavily during exercise because our cells A) need more glucose to be broken down. B) need more ADP to be converted to ATP. C) are producing more CO2 and need to get rid of it. Answer: C 23) Some of the CO2 that is exhaled during breathing is created during A) the reduction of oxygen in the ETC. B) the conversion of pyruvate to acetyl CoA. C) chemiosmosis. D) fermentation. E) glycolysis. Answer: B 24) The metabolic breakdown of one molecule of glucose generates the greatest amount of ATP energy during A) the Krebs cycle. B) mitochondrial matrix reactions. C) ETC. D) fermentation. E) glycolysis. Answer: C

25) How many CO2 molecules are generated from each pyruvate molecule that enters the mitochondrial matrix? A) One B) Two C) Three D) Four E) Five Answer: C 26) To be able to continue, each turn of the Krebs cycle must regenerate which of the following as a final product? A) Pyruvate B) ATP C) Oxaloacetate D) Acetyl CoA E) NADH and FADH2 Answer: C 27) Which of the following is an example of an electron-carrier molecule? A) Citric acid B) ATP C) CO2 D) NADH E) Acetyl CoA Answer: D 28) In aerobic cellular respiration, the ETC receives electrons directly from A) NADH and ATP. B) NADH only. C) NADH and FADH2. D) ATP only. E) FADH2 only. Answer: C 29) In the mitochondrial matrix reactions, the original carbons in pyruvate A) are incorporated into molecules of NADH and FADH2. B) form glucose. C) form the backbone chain of citric acid. D) end up in molecules ofCO2. E) form the ring structure of oxaloacetic acid. Answer: D 30) Chemiosmosis in mitochondria directly results in the synthesis of A) ATP. B) NADH. C) FADH2. D) H2O. E) acetyl CoA. Answer: A

31) What is the final electron acceptor in cellular respiration? A) NADH B) Oxygen C) ATP D) Carbon dioxide E) FADH2 Answer: B 32) During the final events of cellular respiration, oxygen combines with A) hydrogen ions only; water B) energy-depleted electrons only; water C) energy-depleted electrons and hydrogen ions; water D) carbon only; CO2 E) energy-depleted electrons and carbon; CO2

to form

Answer: C 33) From the beginning of glycolysis to the end of the Krebs cycle (excluding the ETC), what has the cell gained from the breakdown of each molecule of glucose? A) 2 molecules of pyruvate B) 2 molecules of ATP, 4 of NADH, and 2 of FADH2 C) 2 molecules of ATP, lactate, and NAD+ D) 2 molecules of ATP and 6 of NADH E) 4 molecules of ATP, 10 of NADH, and 2 of FADH2 Answer: E 34) Oxygen is necessary for cellular respiration because oxygen A) combines with electrons and hydrogen ions to form water. B) reduces glucose to form carbon dioxide and water. C) combines with electrons to form CO2. D) combines with carbon dioxide and water to form glucose. E) combines with carbon to form carbon dioxide. Answer: A 35) The step in aerobic respiration that produces the most ATP per molecule of glucose is A) alcohol fermentation. B) glycolysis. C) lactate fermentation. D) the ETC. E) the citric acid cycle. Answer: D 36) Which of the following parts of the mitochondria is (are) directly involved in the synthesis of ATP during chemiosmosis? A) Matrix only B) Matrix and inner membrane C) Inner membrane only D) Outer membrane only E) Inner and outer membranes Answer: B

37) If ATP is made in the mitochondria, how does it provide energy for reactions in the cytoplasm of the cell? A) ATP is used to make glucose, which is transported to the cytoplasm. B) The energy in ATP is converted to NADH, which travels to the cytoplasm. C) ATP is pumped out from the intermembrane space of the mitochondria to the cytoplasm. D) ATP diffuses into the cytoplasm through large pores in the outer membrane of the mitochondria out. E) ATP is converted to ADP, which is transported to the cytoplasm and converted back to ATP. Answer: D 38) Which of the following most closely matches the correct order of the main events of aerobic cellular respiration? A) Glycolysis, Krebs cycle, ETC, major ATPproduction B) Krebs cycle, ETC, major ATP production, glycolysis C) Major ATP production, pyruvate enters the mitochondrion, Krebs cycle, ETC D) Glycolysis, major ATP production, pyruvate enters the mitochondrion, ETC, Krebs cycle E) Glycolysis, pyruvate enters the mitochondrion, Krebs cycle, major ATP production, ETC Answer: A 39) The products of the Krebs cycle include A) carbon dioxide only. B) ATP only. C) ATP, carbon dioxide, and energy carriers. D) carbon dioxide and energy carriersonly. E) energy carriers only. Answer: C 40) The part of a mitochondrion that is analogous to the stroma of a chloroplast is the A) grana. B) matrix. C) thylakoids. D) outer membrane. E) inner membrane. Answer: B 41) The inner membrane of the mitochondria can be compared functionally to the thylakoid membranes of the chloroplast because both contain a system for A) enzyme synthesis. B) anaerobic respiration. C) pyruvate production. D) glucose synthesis. E) electron transport. Answer: E 42) Which step produces the most ATP? A) Glycolysis B) The Krebs cycle C) The ETC Answer: C

43) Which of the following processes occurs in the cytoplasm? A) Glycolysis B) The Krebs cycle C) The ETC Answer: A 44) Which of the following processes occurs across the mitochondrial membrane? A) Glycolysis B) The Krebs cycle C) The ETC Answer: C 45) Which of the following processes involves hydrogen ions moving through ATP synthase channels, generating ATP molecules? A) Glycolysis B) The Krebs cycle C) The ETC Answer: C 46) The term chemiosmosis is associated with which process? A) Fermentation B) The ETC C) The Krebs cycle D) Glycolysis Answer: B 47) During which of the following processes is CO2 produced? A) The Krebs cycle B) Glycolysis C) The ETC Answer: A 48) Which of the following processes involves citricacid? A) The ETC B) Glycolysis C) The Krebs cycle Answer: C 49) When oxygen is present A) most animal cells carry on fermentation and produce lactate. B) most bacteria and yeasts carry on fermentation. C) two ATP molecules are produced for each glucose molecule. D) most animal cells utilize aerobic cellular respiration. E) most animals convert CO2 to glucose. Answer: D

50) Suppose an organism can alternate between aerobic and anaerobic respiration. If it had to use anaerobic respiration exclusively, how many glucose molecules must it break down to generate the same ATP as it would in aerobic respiration? A) 38 B) 14 C) 19 D) 1 E) 6 Answer: C 51) As a bicyclist pedals up a hill to the finish line of a race and "feels the burn" in his leg muscles, those muscle cells are most likely utilizing A) both cellular respiration and oxygen for maximum ATP production. B) only cellular respiration for maximum ATP production. C) only oxygen for maximum ATP production. D) some lactate fermentation and lactic starting to build up in his muscle tissue causing a cramp. Answer: D 52) Which of the following is common to both fermentation and cellular respiration? A) Krebs cycle B) Electron transport C) Reduction of pyruvate to lactate D) Conversion of pyruvate to acetyl CoA E) Glycolysis Answer: E 53) During which of the following processes is ATP NOT produced? A) Cellular respiration by itself B) Glycolysis by itself C) Fermentation by itself Answer: C 54) Which of the following processes requires oxygen? A) The ETC B) Glycolysis C) Fermentation D) The Krebs cycle Answer: A 55) Within a cell undergoing anaerobic metabolism of glucose, fermentation occurs in the A) phospholipid bilayer of the cellmembrane. B) mitochondrial matrix. C) stroma of the chloroplast. D) nucleus. E) fluid portion of the cytoplasm. Answer: E

56) During the fermentation of one molecule of glucose, the net production of ATP is A) six molecules. B) three molecules. C) eightmolecules. D) two molecules. E) one molecule. Answer: D 57) After fermentation in human cells, lactate is converted to pyruvate in the A) bloodstream. B) bone marrow. C) heart. D) lungs. E) muscles. Answer: E 58) What is the significance of the conversion of pyruvate to lactate during fermentation? A) The oxidation of pyruvate becomespossible. B) NAD+ is regenerated for use in glycolysis. C) Pyruvate becomes available to enter mitochondrial matrix reactions. D) The citric acid cycle is initiated. E) ATP is produced at a higher rate. Answer: B 59) In the absence of oxygen, suppose a single yeast cell undergoes fermentation and uses 100 molecules of glucose. How many molecules of ATP will be generated? A) 36 B) 100 C) 300 D) 400 E) 200 Answer: E 60) In vertebrate animal cells, where does the synthesis of lactate occur? A) Fluid portion of the cytoplasm B) Nucleus C) Mitochondrial inner membranes D) Mitochondrial matrix E) Surface of ribosomes Answer: A 61) How does one account for the bubbles in a glass of beer or champagne? A) Bubbles of CO2 were formed by the yeast cells during glycolysis. B) Bubbles of CO2 were produced by yeast during anaerobic metabolism and were trapped in the bottle. C) Lactate fermentation accounts for thebubbles. D) Bubbles of CO2, produced by aerobic respiration in yeast cells, were trapped in the beverage at bottling. E) The bubbles are simply air bubbles resulting from the brewing process. Answer: B

62) How do fatigued human muscle cells repay an "oxygen debt"? A) The cells convert glucose topyruvate. B) The cells produce more oxygen. C) The cells increase productionof ATP. D) The cells decrease CO2 production. E) The cells convert lactate back to pyruvate. Answer: E 63) In human muscle cells, fermentation (by itself) produces A) water. B) pyruvate. C) adenosine triphosphate. D) lactate. Answer: D 64) End products of the different fermentation processes include all of the following EXCEPT A) lactate. B) ethanol. C) carbon dioxide. D) water. Answer: D 65) Human muscle cells can perform A) lactic acid fermentation and aerobic cellular respiration. B) lactic acid fermentation. C) aerobic cellular respiration. D) alcoholic fermentation, lactic acid fermentation, and aerobic cellular respiration. E) alcoholic fermentation. Answer: A 66) At the end of aerobic cellular respiration, how many total carbon dioxide molecules are produced for each glucose metabolized? A) 36 B) 6 C) 2 D) 32 E) 4 Answer: B 67) Some plans for weight loss include eating a low-carbohydrate diet. In the absence of a lot of glucose in the diet, what other food molecules can be used to extract energy for cellular respiration? A) Fats only B) Protein only C) Protein and fats Answer: C

68) The reason bread dough "rises" is due to the production of A) oxygen gas. B) ethanol. C) lactic acid. D) carbon dioxide gas. Answer: D 69) Bacteria in our mouths feed off the sugars in foods that we eat. As these bacteria ferment the sugars, they generate a product that can cause dental cavities. What is this product? A) Acetyl CoA B) Lactic acid C) Citricacid D) Hydrochloric acid E) Pyruvate Answer: B 70) Which of the following metabolic processes directly utilizes oxygen? A) Glycolysis B) ETC C) Alcohol fermentation D) Lactic acid fermentation Answer: B 71) Cyanide poisoning occurs because cyanide inhibits an enzyme in the electron transport pathway. Which of the following is the reason why cyanide poisoning becomes deadly? A) Glycolysis stops. B) Oxygen is reduced to water. C) ATP is no longer produced by chemiosmosis. D) Cells switch to anaerobic fermentation. Answer: C 72) During chemiosmosis, a hydrogen ion gradient is linked to the production of ATP. A) True B) False Answer: A 73) Glycolysis and the Krebs cycle reactions both occur in the mitochondria. A) True B) False Answer: B 74) Carbon dioxide is considered a waste product of cellular respiration. A) True B) False Answer: A 75) The process of fermentation is energetically more efficient than that of cellular respiration. A) True B) False Answer: B

SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 76) In the cell, more than half of the energy produced by the metabolic breakdown of glucose is released as and the remaining energy is stored in . Answer: heat; ATP 77) The organelles responsible for the bulk of ATP production via cellular respiration are the

Answer: mitochondria 78)

is the first stage in glucose metabolism and does not require oxygen. Answer: Glycolysis

79)

is a series of reactions, occurring under aerobic conditions, in which large amounts of ATP are produced from the breakdownof glucose. Answer: Cellular respiration

80) Most of the ATP produced during cellular respiration is generated in the mitochondrial after the movement of hydrogen ions through ATP-synthesizing proteins in the inner membrane of the mitochondrion. Answer: matrix 81)

is the process by which hydrogen ions move via a concentration gradient through ATP-synthesizing enzymes, resulting in the production of ATP. Answer: Chemiosmosis

82) In the process of cellular respiration, a molecule of , and .

is completely broken downto form

Answer: glucose; H2O; ATP; carbon dioxide 83) Two possible end products of fermentation are (as is produced by our muscle cells under anaerobic conditions) and (as is produced by yeast under anaerobicconditions). Answer: lactate; carbon dioxide (or ethanol) 84) The conversion of glucose to lactate is a form of

Answer: fermentation 85) Yeast in a bottle of champagne produces

and

Answer: ethanol; carbon dioxide 86) Briefly compare and contrast the processes of cellular respiration and photosynthesis. Answer: During photosynthesis, carbon dioxide and water are combined with light energy to produce glucose and oxygen. In cellular respiration, glucose, with oxygen, is broken down into carbon dioxide, water, and ATP. Both processes use chemiosmosis to produce ATP. 87) How does a lack of oxygen affect energy availability in animals? Answer: Low oxygen levels result in little ATP production via chemiosmosis and a switch to an anaerobic, and less efficient, fermentation pathway of metabolism.

88) Briefly describe the three main steps of aerobic glucose metabolism. Answer: (1) Glycolysis (glucose converted to pyruvate with two molecules of ATP and two of NADH produced); (2) pyruvate conversion to acetyl CoA and the Krebs cycle (pyruvate converted to CO2 with two molecules of ATP, eight of NADH, and two of FADH2 produced); and (3) ETC (ETC and chemiosmosis with 32 to 34 molecules of ATP produced) 89) Respiration rates are measured by the amount of oxygen per gram of tissue per hour. In a series of experiments, it was determined that a warm-blooded mouse requires 2.5 milliliters of O2 per gram of tissue per hour, whereas a cold-blooded crayfish requires 0.047 milliliter of O2 per gram of tissue per hour. Why is there such a dramatic difference in respiration rates between these animals? Answer: Warm-blooded animals require more energy to maintain their higher body temperature and greater metabolic rate, and energy production is directly proportional to oxygen utilization by the ETC. 90) How does baker's yeast in bread dough make the bread rise? Answer: Bread rises due to the production of carbon dioxide during alcohol fermentation. 91) Why is it important that NAD+ molecules are regenerated during fermentation? Answer: Glycolysis would stop when all the NAD+ molecules were used up, resulting in no energy production for that cell. 92) Imagine that you are running a marathon, and at the end of the race, you sprint to the finish line. Describe how your muscle cells are getting energy. Discuss the processes involved and detail the differences that occur at the start of your run and toward the end of your run. Answer: Students should address the shift from aerobic cellular respiration to anaerobic lactate fermentation as oxygen becomes scarce for the muscle cells. 93) The French biochemist and microbiologist Louis Pasteur investigated the metabolism of yeast, which can survive under both aerobic and anaerobic conditions. He observed that the yeast consumed sugar at a much faster rate under anaerobic conditions than they did under aerobic conditions. Explain this "Pasteur effect." Answer: Under anaerobic conditions, fermentation is being used, producing only two ATP molecules per glucose molecule. Under aerobic conditions, cellular respiration is being used, producing 36 to 38 ATP molecules per glucose molecule. More glucose is thus required under anaerobic conditions to yield the same amount of ATP as is produced under aerobic conditions. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

94) In the Krebs cycle, electron-carrier molecules are produced as a result of individual reactions. NAD+ is reduced as one chemical compound is converted to another EXCEPT during the conversion of

A) isocitrate to α-ketoglutarate. B) malate to oxaloacetate. C) succinate to fumarate. D) α-ketoglutarate to succinate. Answer: C

95) If only one molecule of pyruvate (instead of two) were produced per glucose molecule metabolized in glycolysis, then which of the following would be produced after glycolysis and before the electron transport chain?

A) 2 ATP, 6 NADH, and 2 FADH2 B) 1 ATP, 3 NADH, and 1 FADH2 C) 1 ATP, 1 NADH, and 1 FADH2 D) 1 ATP, 4 NADH, and 1 FADH2 Answer: D 96) Some people trying to lose weight have gone on the Atkins diet, in which they eat mostly high-protein, low-carbohydrate foods such as meat, cheese, and eggs. The amino acids in these protein-rich diets, such as alanine, glycine, and serine, can be converted to pyruvate by deamination (removal of the amino group). Based on this scenario as well as your knowledge of cellular respiration, how many ATP, NADH, and FADH2 molecules will be generated from one molecule of alanine during the mitochondrial matrix reactions? Hint: Only consider the reactions from the point at which the alanine carbons enter cellular respiration. A) 0 FADH2, 1 NADH, and 2 ATP B) 2 FADH2, 3 NADH, and 2 ATP C) 1 FADH2, 4 NADH, and 1 ATP D) 2 FADH2, 6 NADH, and 2 ATP E) 1 FADH2, 1 NADH, and 1 ATP Answer: C

SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 97) In the 1940s, some physicians prescribed low doses of a drug called dinitrophenol (DNP) to help patients lose weight. This unsafe drug was quickly abandoned after a few patients died. DNP affects cells by uncoupling the chemiosmotic machinery and making the inner mitochondrial membrane "leaky" to hydrogen ions. Explain how DNP caused weight loss and, ultimately, death in these dieters. Answer: No hydrogen ion gradient could be established, so little ATP was produced through the process of cellular respiration. In turn, consumed (dietary) energy and stored (fat) energy were metabolized to try to give the body enough ATP to survive, but without success.

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Which of the following is TRUE of cell division? A) Each daughter cell receives half of the cytoplasm from the parent cell. B) Three daughter cells are produced from one parent cell. C) The hereditary information is DNA in the parent cell and RNA in the daughter cells. D) Each daughter cell receives one-third of the hereditary information in the parent cell. Answer: A 2)

Which of the following statements about stem cells is TRUE? A) They are able to differentiate into a variety of cell types. B) They are found only inembryos. C) They are permanently differentiated and cannot further divide. D) They are "perpetual" parent cells that never produce daughter cells. E) They are found only in embryos and in the bone marrow of adults. Answer: A 3) The structure of DNA most resembles which of the comparisons below A) a straight road. B) beads on a string. C) a spiralstaircase. D) a pleated sheet. Answer: C 4) All of the following may be found in a DNA nucleotide EXCEPT A) thymine. B) deoxyribose. C) phospholipid. D) adenine. Answer: C

Which of the following is the correct structure of a nucleotide? A) Base-sugar-base B) Phosphate-sugar-phosphate C) Phosphate-sugar-base D) Phospholipid-base-sugar Answer: C 6) Which of the following statements is FALSE? A) Genes and chromosomes are duplicated during prophase. B) Homologous chromosomes do not pair during mitosis. C) Each species has a specific number of chromosomes. D) New nuclei are formed during telophase. Answer: A 7) Genetic inheritance is based on what type of molecule? A) Enzymes B) DNA C) Proteins D) mRNA Answer: B

8) A phosphate group binds to what molecule to create the "backbone" of the DNA molecule? A) Adenine B) Deoxyribose C) Ribose D) Other phosphate molecules Answer: B 9) The repeating sequence of cells dividing, growing, and dividing again is called A) fission. B) stem cell differentiation. C) homologous differentiation. D) the cell cycle. Answer: D 10) Which of the following is an example of asexual reproduction in eukaryotes? A) Prokaryotic fission in the bacterium E. coli B) Budding in the protistan Hydra C) The union of sperm and egg in sea urchins D) Meiosis in plants Answer: B 11) Which of the following are permanently differentiated cells? A) Stem cells B) Newly formed daughter cells C) Bone marrow cells D) Most braincells Answer: D 12) As a result of mitosis, each of your body cells A) changes genetically as you grow and develop. B) contains only the genetic information needed for that type of cell. C) is genetically identical to all other body cells. D) contains unique genetic information. Answer: C 13) When a cell divides via asexual reproduction A) each daughter cell receives a nearly perfect copy of the parent cell's genetic information. B) each daughter cell receives exactly half the genetic information in the parent cell. C) the genetic information is randomly parceled out to the daughter cells. D) each daughter cell receives the same amount of genetic information that was in the parent cell, but it has been altered. Answer: A 14) Cells with two of each kind of chromosome are described by the term A) haploid. B) tetraploid. C) triploid. D) polyploid. E) diploid. Answer: E

15) Which of the following statements is FALSE? A) More than 1,000 chromosomes are found in some organisms. B) The number of chromosomes is the same for all members of a species. C) The number of chromosomes remains constant throughout a life cycle. D) The more highly evolved a species is, the more chromosomes it possesses. E) Germ cells contain half as many chromosomes as somatic cells. Answer: D 16) Which statement is TRUE of the behavior of chromosomes in mitosis? A) The sister chromosomes are not identical because of breakages in the DNA. B) If the original number of chromosomes was 46, each new cell will have 23. C) Each new cell receives copies of all the original chromosomes. D) All chromosomes are duplicated except the sex chromosomes. E) Each new cell receives half of the number of chromosomes in the original cell. Answer: C 17) A bacterial cell splits into two new cells by a process called A) mitosis. B) forming a cell plate. C) duplication. D) prokaryotic fission. E) forming a cell furrow. Answer: D 18) What does the bacterial genome consist of? A) DNA in mitochondria B) One circular RNA molecule C) Many rod-like DNA molecules withprotein D) One circular DNA molecule E) Several circular DNA molecules Answer: D 19) What is the longest-lasting phase of the prokaryotic cell cycle? A) Fission of the plasma membranes at the cell equator B) Cell growth and DNA replication C) Prokaryotic fission D) Meiosis Answer: B 20) Under ideal conditions, the prokaryotic cell cycle can A) create more than two daughter cells per cell division. B) occur in less than a half an hour. C) skip prokaryotic fission. D) involve sexual reproduction. Answer: B

21) How do prokaryotic and eukaryotic chromosomes differ? A) Prokaryotic chromosomes are not contained in a membrane-bound organelle. B) Eukaryotic chromosomes occur singly, and prokaryotic chromosomes occur as pairs. C) Genetic information is stored as DNA in eukaryotic cells and as proteins in prokaryotic cells. D) Prokaryotic chromosomes are not made from nucleotides. Answer: A 22) In prokaryotes, the DNA molecule is A) single-stranded. B) more than 1.8 meters (6 feet) long when uncoiled. C) made of sugars andlipids. D) circular. Answer: D 23) In prokaryotes, the term prokaryotic fission specifically refers to A) the growth phase of the cell cycle. B) the addition of a new plasma membrane between what will become two daughter cells. C) the attachment of replicated DNA to the plasma membrane. D) asexual reproduction. Answer: D 24) In prokaryotes, the daughter cells produced by prokaryotic fission A) cannot replicate themselves. B) can reproduce either by prokaryotic fission or by the production of gametes. C) contain half the DNA of the original parent cell. D) are, with the exception of random mutations, genetically identical to the parent cell. Answer: D 25) The most common method of bacterial reproduction is A) budding. B) mutation. C) meiosis. D) prokaryotic fission. Answer: D 26) Replication ofthe bacterial A) mitochondria B) chromosome C) gamete D) nucleus

is required before the bacterial cell can be duplicated.

Answer: B 27) What is the function of the histones that are found in a chromosome? A) They hold the DNA strands together in a form called the double helix. B) They contain the genes that code for various traits. C) They bind nucleotides together to form a single strand of DNA. D) They provide support for the DNA to form into a supercoiled structure. Answer: D

28) How many nucleotides are in a human chromosome? A) Four B) Thousands C) Two D) Millions Answer: D 29) Which of the following is the longest? A) An uncondensed eukaryotic chromosome B) An uncondensed prokaryotic chromosome C) A condensed prokaryotic chromosome D) A condensed eukaryotic chromosome Answer: A 30) The terminal ends or "tips" of a chromosome are called A) telomeres. B) loci. C) centromeres. D) genes. E) chromatids. Answer: A 31) The site on a chromosome where microtubules attach during cell division is the A) centromere. B) chromatid. C) telomere. D) histone. E) locus. Answer: A 32) In a eukaryotic cell that is undergoing cell division, what will become a new chromosome? A) A centromere B) A locus C) A telomere D) A chromatid Answer: D 33) When the DNA in a cell is uncoiled and spread throughout the nucleus, it is called A) chromatin. B) a centromere. C) a chromosome. D) a chromatid. Answer: A 34) A portion of a DNA molecule wound around a "bead" of histone protein is called a A) cell cycle. B) spindle. C) centromere. D) furrow. E) nucleosome. Answer: E 5

35) When chromosomes become visible during prophase of mitosis, it is the result of A) uncoiling. B) addition of proteins to the DNA. C) DNA synthesis. D) condensation. E) chromatid duplication. Answer: D 36) Proteins that resemble beads on which DNA molecules are wound are called A) motor proteins. B) spindles. C) kinetochores. D) histones. E) centrioles. Answer: D 37) Which of these statements concerning the centromere is NOT true? A) It is the attachment site for microtubules. B) It anchors proteins to DNA. C) Its position along the chromosome varies. D) It is temporary. E) It appears to join duplicated DNAs. Answer: B 38) DNA replication occurs A) between the gap phases (G1 and G2) of interphase. B) during prophase of meiosis. C) at any time during celldivision. D) during prophase of mitosis. E) immediately before prophase of mitosis. Answer: A 39) Chromosomes are duplicated during what portion of the cell cycle? A) S B) G1 C) D D) G2 E) M Answer: A 40) Cells spend most of their time in what phase? A) Prophase B) Interphase C) Cytokinesis D) Mitosis Answer: B

41) During which phase do chromosomes first become visible? A) Interphase B) Prophase C) Metaphase D) Telophase Answer: B 42) Which of the following is the proper sequence for mitosis (I. metaphase, II. telophase, III. prophase, IV. anaphase)? A) III, I, IV, II B) I, III, IV, II C) IV, I, III, II D) III, IV, I, II E) I, II, III, IV Answer: A 43) The chromosomes and genes are actually replicated during A) interphase. B) metaphase. C) telophase. D) anaphase. E) prophase. Answer: A 44) Four of the five answers listed below are stages of actual nuclear division. Select the exception. A) Interphase B) Anaphase C) Telophase D) Metaphase E) Prophase Answer: A 45) The interval before the onset of DNA replication is A) the G1 stage. B) the S stage. C) the G2 stage. D) the M stage. E) all stages. Answer: A 46) Which of the following organisms does NOT reproduce its cells by mitosis and cytokinesis? A) A bacterium B) A cow C) A banana tree D) A cockroach E) A mushroom Answer: A

47) During which phase of the eukaryotic cell cycle does DNA and chromosome replication occur? A) The G1 phase of interphase B) The S phase of interphase C) Cytokinesis D) The mitotic phase Answer: B 48) During which phase of the eukaryotic cell cycle do growth and nutrient acquisition occur? A) The G1 phase of interphase B) The mitotic phase C) Cytokinesis D) The S phase of interphase Answer: A 49) All of the following eukaryotes can reproduce asexually EXCEPT A) domestic dogs. B) Amoeba. C) Hydra. D) Paramecium. E) aspen trees. Answer: A 50) At what phase in the cell cycle does DNA replication occur? A) S B) G1 C) G0 D) M Answer: A 51) Which of the following is NOT correct? A) Cytokinesis is a part ofmitosis. B) All somatic cells are produced by mitosis. C) Mitosis produces genetically identical cells. D) Metaphase occurs before anaphase. Answer: A 52) The two main stages of the cell cycle are called A) mitosis and interphase. B) telophase and cytokinesis. C) cytokinesis and mitosis. D) interphase and anaphase. Answer: A 53) Beginning with a newly formed daughter cell, what is the order of the other stages of the eukaryotic cell cycle? A) G1, S, G2, mitosis B) Mitosis, S, G1, G2 C) G1, G2, mitosis, S D) Mitosis, G1, G2, S Answer: A

54) What structure is responsible for moving the chromosomes during mitosis? A) nucleolus B) spindle C) nuclear membrane D) cytoplasm Answer: B 55) Each chromosome consists of two A) centrioles. B) chromatids. C) daughter cells. D) centrofibers. Answer: B 56) The spindle fibers are produced by the A) centrioles. B) chromatin. C) nucleus. D) chromosomes. Answer: A 57) A contractile ring forms in which type of cells? A) Plants B) Bacteria and plants C) Animal D) Animals and plants Answer: C 58) A cell with 10 chromosomes undergoes mitosis and cell division. How many daughter cells are produced, and what number of chromosomes do they have? A) 4 daughter cells, 20 chromosomeseach B) 2 daughter cells, 5 chromosomes each C) 1 daughter cell, 10 chromosomes each D) 2 daughter cells, 10 chromosomes each Answer: D 59) The spindle apparatus begins to become visible during A) telophase. B) interphase. C) anaphase. D) prophase. E) metaphase. Answer: D 60) In eukaryotic cells, which of the following can occur during the stages of mitosis? A) Synapsis and crossing over B) Duplication of chromatids C) Replication of DNA D) Fragmentation and disappearance of nuclear envelope and nucleolus E) All of these Answer: D 9

61) The distribution of cytoplasm to daughter cells is accomplished during A) cytokinesis. B) prokaryotic fission. C) mitosis. D) karyokinesis. E) meiosis. Answer: A 62) The chromosomes are aligned at the spindle equator during A) metaphase. B) anaphase. C) telophase. D) prophase. E) interphase. Answer: A 63) Four of the five answers listed below assist in chromosome movement. Select the exception. A) Centromere B) Kinetochores C) Nuclear envelope D) Centriole E) Spindle microtubules Answer: C 64) The chromosomes are moving to opposite poles during A) metaphase. B) interphase. C) prophase. D) anaphase. E) telophase. Answer: D 65) If a parent cell has 16 chromosomes, how many sister chromatids will be present after duplication of the chromosomes? A) 32 B) 8 C) 16 D) 4 E) 64 Answer: A 66) The spindle apparatus is madeof A) chromatids. B) microtubules. C) Golgi bodies. D) endoplasmic reticulum. E) nucleoprotein. Answer: B

67) Chromatids that are attached at the centromere are called what kind of chromatids? A) Mother B) Programmed C) Either mother or daughter. D) Daughter E) Sister Answer: E 68) In which of the stages below does each chromosome consist of two DNA molecules? (I. metaphase, II. telophase, III. prophase, IV. anaphase) A) III and IV B) I, II, III, and IV C) I, III, and IV D) I and III E) I, II, and III Answer: D 69) Four of the five answers listed below are events occurring during mitosis. Select the exception. A) Division of centromere B) Lining up of chromosomes at the cellular equator C) Migration of chromosomes to opposite ends of the cell D) Attachment of spindle microtubules to centromeres E) Chromosome replication Answer: E 70) The chromosomes have arrived at opposite poles during A) metaphase. B) prophase. C) interphase. D) anaphase. E) telophase. Answer: E 71) The chromatids detach from one another and become visibly separate chromosomes during A) anaphase. B) interphase. C) metaphase. D) telophase. E) prophase. Answer: A 72) The nuclear membrane re-forms during A) metaphase. B) telophase. C) interphase. D) prophase. E) anaphase. Answer: B

73) In mitosis, if a parent cell has 16 chromosomes, each daughter cell will have how many chromosomes? A) 32 B) 16 C) 4 D) 64 E) 8 Answer: B 74) In plant cytokinesis, cellulose is laid down forming A) a cleavage furrow. B) a middle lamella. C) a cell plate. D) a plasma membrane. E) cell walls. Answer: C 75) What is the function of centrioles? A) They produce microtubules for the chromosomes to migrate along as they move to opposite poles of the cell. B) They are required for DNAreplication. C) They are the structure that holds the two daughter chromatids together at the centromere. D) They cause cytokinesis via the concentric shortening of microtubules. Answer: A 76) Which of the following is correct? A) The nucleolus reappears following telophase. B) Interphase is characterized by little cellular activity, as the cell is resting to prepare for the next mitotic event. C) The chromosomes shorten and thicken during prophase. D) All of the above. Answer: C 77) During which phase of mitosis do the chromosomes line up along the middle of the dividing cell? A) Telophase B) Metaphase C) Anaphase D) Prophase Answer: B 78) Which of the following is the correct sequence of stages in mitotic cell division? A) Prophase → metaphase → anaphase → telophase B) Anaphase → telophase → prophase → metaphase C) Metaphase → prophase → anaphase → telophase D) Telophase → anaphase → prophase → metaphase Answer: A

79) During which phase of mitosis do sister chromatids separate from each other? A) Anaphase B) Prophase C) Metaphase D) Telophase Answer: A 80) During which phase of mitosis do chromosomes condense? A) Anaphase B) Prophase C) Metaphase D) Telophase Answer: B 81) During which phase of mitosis do the centromeres line up along the cell equator? A) Anaphase B) Prophase C) Metaphase D) Telophase Answer: C 82) Which phase of mitosis is a "preparatory" step involving the development of spindle microtubules? A) Anaphase B) Prophase C) Metaphase D) Telophase Answer: B 83) Which phase of mitosis involves the shortening of the microtubules as the chromosomes move toward the poles? A) Anaphase B) Prophase C) Metaphase D) Telophase Answer: A 84) Nuclear envelopes form during which phase of mitosis? A) Anaphase B) Prophase C) Metaphase D) Telophase Answer: D 85) During which phase of mitosis does cytokinesis occur? A) Anaphase B) Prophase C) Metaphase D) Telophase Answer: D

86) One difference between mitotic cell division in animal cells and plant cells is that A) plant cells do not undergo anaphase. B) in plant cells, cytokinesis occurs as vesicles deposit carbohydrates along the equator. C) animal cells do not undergo telophase. D) in animal cells, cytokinesis occurs as vesicles deposit carbohydrates along the equator. E) cytokinesis occurs in animal cells but has not yet been observed in plant cells. Answer: B 87) The protein-containing structure on the centromere where microtubules attach is called the A) spindle. B) kinetochore. C) centriole. D) cell plate. Answer: B 88) Kinetochores attach A) sister chromatids to each other. B) chromatids to spindle microtubules. C) chromosomes to ribosomes. D) chromosomes to each other. Answer: B 89) In animal cells, spindle microtubules originate from structures called A) cyclins. B) chromatids. C) histones. D) centrioles. Answer: D 90) What occurs immediately following cytokinesis? A) Anaphase B) Telophase C) Prophase D) The G1 portion of interphase Answer: D 91) Mitosis is division of the , whereas cytokinesis is division of the A) nucleus; chromosome B) prokaryotic cell; eukaryotic cell C) chromatid; chromosome D) nucleus; cytoplasm

Answer: D 92) During plant cell cytokinesis, what is the name of the structure that forms between the daughter cell nuclei and eventually will become the new cell wall? A) Cell plate B) Constriction ring C) Vesicle wall D) Kinetochore Answer: A

93) Movement of the chromosomes during anaphase would be most affected by a drug that A) reduced cyclin concentrations. B) prevented attachment of the microtubules to the kinetochore. C) prevented shortening of microtubules. D) prevented elongationof microtubules. E) increased cyclin concentrations. Answer: C 94) What causes the rhythmic change in cyclin concentration in the cell cycle? A) The changing ratio of cytoplasm to genome B) The binding of PDGF to receptors on the cell surface C) The cascade of increased production once the protein is phosphorylated by Cdk D) Its destruction by an enzyme phosphorylated by the cyclin-Cdk complex E) An increase in production of a Cdk once the restriction point is passed Answer: D 95) What are enzymes called that control the activities of other proteins by phosphorylating them? A) cyclins B) kinases C) phosphatases D) chromatin E) ATPases Answer: B 96) Cdks bind with A) histones B) cyclins C) p53 D) kinases E) MPF

, enabling the Cdks to function as enzymes.

Answer: B 97) Mitosis is controlled atthe A) G1 B) G2 C) M D) C E) S

checkpoint.

Answer: C 98) DNA replication is controlled at the A) S B) G2 C) M D) G1 E) C

checkpoint.

Answer: B

99) The cell cycle is controlled in most cellsby A) time-after a certain length of time the cell divides. B) a series of checkpoints. C) cell size, when the cell reaches a certain size, it divides. D) different cells exhibit different control strategies, any of the 4 above can be found in eukaryotic organisms. E) the completion of one phase which triggers the beginning of the next. Answer: B 100) What would be a consequence of a mutation that disables the production of cyclin-dependent kinases (Cdks)? A) Cell-cycle control would not bepossible. B) DNA would not contain any phosphate groups. C) Telomere length would be shortened significantly. D) The nuclear envelope woulddisintegrate. Answer: A 101) Cdks are activated only when they bind to A) cyclin. B) centrioles. C) chromatids. D) cytosine. Answer: A 102) Kinases are responsible for the addition of A) cyclin B) nitrogen C) phosphate D) phosphorus

to other proteins.

Answer: C 103) Growth factors stimulate A) cells to divide. B) Cdks to synthesize enzymes that digest cyclins. C) the cell to ignore the checkpoints of the cell cycle. D) the cell to skip the S and G1 phases of interphase and undergo mitosis directly. Answer: A 104) Cancer is essentially A) the creation of extra checkpoints in the cell cycle. B) a never-ending repetition of the S phase of the cellcycle. C) the binding of cyclins and Cdks. D) unregulated mitotic cell division. Answer: D 105) Which of the following is the correct sequence in a cyclin-Cdk pathway? A) Growth factor → cyclin → Cdk → receptor → DNA replication B) Growth factor → receptor → cyclin → Cdk → DNA replication C) Receptor → cyclin → Cdk → growth factor → DNA replication D) Growth factor → receptor → Cdk → cyclin → DNA replication Answer: B

106) All of the following play a role in the development of cancer EXCEPT A) mutations. B) a large supply of Cdks stimulating cell division. C) uncontrolled cell division. D) inhibition of Cdk and blocking of DNA replication. Answer: D 107) In eukaryotic cells, chromosomes are composed of both DNA and proteins. A) True B) False Answer: A 108) Most prokaryotes reproduce via a form of asexual reproduction called prokaryotic fission. A) True B) False Answer: A 109) Bacteria divide through a process called binaryfission. A) True B) False Answer: A 110) The uncoiled DNA in a eukaryotic cell is much longer than the cell itself. A) True B) False Answer: A 111) Eukaryotic chromosomes are made up of only DNA. A) True B) False Answer: B 112) Chromosome replication takes place duringinterphase. A) True B) False Answer: A 113) Cytokinesis takes place during metaphase. A) True B) False Answer: A 114) In prophase, the nuclear membranedisappears. A) True B) False Answer: A

115) Following telophase in animal cells, a cell plate begins to form. A) True B) False Answer: A 116) Normal human cells can go on dividing indefinitely. A) True B) False Answer: A SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 117) The abbreviation DNAstands for

Answer: deoxyribonucleic acid 118) Nucleotides are the building blocks of

and

Answer: DNA; RNA (or nucleic acids) 119) Inside the nucleus, the two strands of nucleic acids that exist in the form of a double helix make up the molecule called . Answer: DNA 120) DNA is a polymer composed of subunits called

Answer: nucleotides 121) The units ofinheritance, called , are segments of the DNA of a chromosome, ranging from a few hundred to many thousands of nucleotides in length. Answer: genes 122) The term organism.

means that stem cells retain the capacity to divide, in some cases for the entire life of the

Answer: self-renewal 123) Heritable information exists as discrete units called genes, which are located on

Answer: chromosomes 124) The term

(from Greek words meaning "cell movement") refers to the division of the cytoplasm.

Answer: cytokinesis 125) During development, after an injury, or to compensate for normal wear and tear, many cells in the body release hormone-like molecules called . Answer: growth factors 126) What sugar is found in DNA nucleotides? Answer: deoxyribose 127) Name the four different nitrogen-containing bases that are found in DNA. Answer: adenine, thymine, guanine, and cytosine

128) The eukaryotic cell cycle consists of two phases, interphase and mitotic cell division. What are the substages that take place within each of these two phases? Answer: Interphase consists of G1, S, and G2. Mitotic cell division consists of prophase, metaphase, anaphase, telophase and cytokinesis. 129) Based on your understanding of mitosis, explain the function of this process, where it takes place, and the result of doing this type of cell division? Answer: Mitosis is used for several different functions, including asexual reproduction, growth, and repair within the body. Mitosis takes place in somatic (or body) cells. Overall, it produces clones or exact copies (excluding mutational events) of cells. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 130) Based on this figure, the rules for nucleotide base pairing in DNA must be

A) adenine with thymine, and guanine with cytosine. B) adenine with cytosine, and guanine with thymine. C) adenine with guanine, and cytosine with thymine. D) adenine with thymine, and guanine with phosphate. Answer: A

131) Based on this figure, what would be the consequence of exposure to a synthetic chemical in the environment that mimics the structure and shape of a growth factor?

A) The cyclin-Cdk complex would still occur but would not stimulate DNA replication. B) DNA replication would be stimulated even though the actual growth factor was not present. C) Cdk and cyclin would not bind to each other. D) Cyclin production would not be "turned on." Answer: B SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 132) For the question below, suppose that the somatic cells of humanoid X contain a total of 4 chromosomes [2N = 4] (or 2 pairs of chromosomes, [N = 2]). How many chromatids and chromosomes are present at the following stages of mitosis? Answers should be filled in for the blank spaces in the table below. Stage # of CHROMATIDS # of CHROMOSOMES G1 phase of MITOSIS G2 phase of MITOSIS Anaphase of MITOSIS Prophase of MITOSIS Answer: See table below. Stage G1 phase of MITOSIS G2 phase of MITOSIS Anaphase of MITOSIS Prophase of MITOSIS

# of CHROMATIDS

# of CHROMOSOMES

8 8 8

4 8 4

133) In mitosis, three major check points are built into the cell cycle. These checkpoints make sure that certain criteria are met before proceeding to the next step. Explain the major responsibilities of the checkpoints between the following steps: between G1 to S, between G2 to mitosis, and between metaphase to anaphase. Answer: At the juncture of G1 to S: ensures that the cell's DNA is suitable for replication. At the juncture of G2 to mitosis: ensures that DNA has been completely and accurately replicated. Between metaphase and anaphase: ensures that all the chromosomes are attached to the spindle and aligned properly at the equator of the cell.

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Different, or alternative, forms of the same gene are called A) homologous. B) chromatids. C) genetomorphs. D) mutants. E) alleles. Answer: E 2) Which of the following is NOT true of human chromosomes? A) There are 23 pairs of chromosomes. B) Human gametes end up with two of each type of 23 chromosomes. C) The diploid number is 46. D) The haploid number is 23. E) Human gametes end up with one of each type of 23 chromosomes. Answer: B 3) If meiosis did NOT occur in sexually reproducing organisms A) eggs would be haploid, but sperm would be diploid. B) gametes would be haploid. C) the chromosome number would double in each generation. D) growth of the zygote would be halted. E) mitosis would be sufficient. Answer: C 4) Meiosis typically results in the production of A) two haploid cells. B) one triploid cell. C) four haploid cells. D) four diploidcells. E) two diploid cells. Answer: C 5) Four of the five answers listed below are haploid. Select the exception. A) Sperm B) Egg C) Meiospore D) Gametophyte E) Zygote Answer: E 6) Which is NOT a typical site for the occurrence of meiosis? A) Plant ovary B) Human ovary C) Plant root cells D) Plant anther E) Human testis Answer: C

7) Four of the five answers listed below are characteristic of meiosis. Select the exception. A) Involves synapsis B) Produces haploid cells C) Reduces the number of chromosomes D) Results in producing genetically identical cells E) Involves two divisions Answer: D 8) Copies of chromosomes linked together at their centromeres at the beginning of meiosis are appropriately called what kind of chromatids? A) Mother B) Daughter C) Sister D) Homologous Answer: C 9) Asexually produced daughter cells are A) identical to the parental cell. B) identical to each other and to the parental cell. C) identical to each other. D) different from parental cell. E) different from eachother. Answer: B 10) Homologous chromosomes A) may exchange parts during meiosis. B) pair up during meiosis. C) are in pairs, one chromosome of each pair from the father and one from the mother. D) have alleles for the same characteristics even though the gene expression may not be the same. E) All of the choices are correct. Answer: E 11) Through meiosis A) the diploid chromosome number is reduced to haploid. B) parental DNA is divided and distributed to forming gametes. C) alternate forms of genesare shuffled. D) offspring are provided with new gene combinations. E) All of the choices are correct. Answer: A 12) Sexual reproduction A) produces genetic clones. B) results in new combinations of genetic traits. C) requires less tissue differentiation than asexual reproduction. D) produces genetic clones and requires less tissue differentiation than asexual reproduction. E) leads to uniform characteristics in a population. Answer: B

13) Which of the following statements is NOT true? A) Sexual reproduction puts together new combinations of genes. B) In sexual reproduction, both meiosis and fertilization must occur during the life cycle. C) Sexual reproduction produces clones. D) In asexual reproduction, the parent passes a complete set of genes to its offspring. E) In sexual reproduction, a human offspring receives two genes for every trait. Answer: C 14) Sea stars are genetically different from each other and from their parents. These genetic differences are the result of A) sexual reproduction. B) cloning. C) mitosis. D) asexual reproduction. Answer: A 15) Which of the following is NOT associated with meiosis? A) Sexual reproduction B) Sperm and egg C) Germ cells D) Somatic cells E) Reduction of number of chromosomes Answer: D 16) In humans, the male determines the sex of the child because males have A) one X and one Y chromosome. B) two X chromosomes. C) two Y chromosomes. D) 46 chromosomes. Answer: A 17) In humans, gametes contain A) 22 autosomes and 1 sex chromosome. B) 45 autosomes and 1 sex chromosome. C) 22 autosomes and 2 sex chromosomes. D) 1 autosome and 22 sex chromosomes. E) 1 autosome and 45 sex chromosomes. Answer: A 18) An advantage of sexual reproduction and meiosis is that A) organisms remain stable in a changing environment. B) production of gametes generates energy. C) many offspring are produced in a short period of time. D) it increases genetic diversity. Answer: D

19) The process of meiosis A) begins with haploid cells and ends with diploid cells. B) begins with haploid cells and ends with haploid cells. C) begins with diploid cells and ends with diploid cells. D) begins with diploid cells and ends with haploid cells. Answer: D 20) Strictly speaking, mitosis and meiosis are divisions of the A) nucleus. B) nucleus and chromosomes. C) chromosomes. D) nucleus, cytoplasm, and chromosomes. E) cytoplasm. Answer: B 21) Some organisms are capable of asexual or sexual reproduction. Under favorable conditions, reproduction proceeds asexually. When conditions become more stressful, reproduction switches to a sexual mode. Why? A) Sexual reproduction is simple and more rapid, allowing larger numbers of offspring to be produced. B) Asexual reproduction requires more energy. C) Sexual reproduction requires two separate individuals who can mutually provide nutrient support during stress. D) Sexual reproduction produces individuals with new combinations of recombined chromosomes increasing diversity. Answer: D 22) If a mammal is born without the ability to produce EGF (epidermal growth factor), then its A) Cdks will not function properly. B) ability to increase cell division when needed would diminish. C) lickedwounds will heal faster than usual. D) cell cycles will not contain the proper checkpoints. Answer: B 23) The different forms of a gene-for example, those responsible for eye color-are called A) sister chromatids. B) cyclins. C) receptors. D) telomeres. E) alleles. Answer: E 24) Sexual reproduction allows for A) clones of parent cells to be produced more quickly and efficiently than does prokaryotic fission. B) haploid individuals to pass their genes on to the next generation. C) random mutations to occur at a faster rate than does asexual reproduction. D) greater genetic diversity in offspring compared to asexual reproduction. Answer: D

25) A photograph of all the stained, prepared chromosomes in a eukaryotic cell is referred to as a A) chromatid. B) centromere. C) karyotype. D) telomere. Answer: C 26) In a typical human body (somatic) cell, how many total chromosomes are there? A) 1 B) 23 C) 2 D) 46 Answer: D 27) A typical human body cell contains how many sex chromosomes? A) 2 B) 46 C) 1 D) 23 Answer: A 28) The sex-determining chromosomes of a human male are the A) Z and Z chromosomes. B) Y and Y chromosomes. C) X and Y chromosomes. D) Y and Z chromosomes. E) X and X chromosomes. Answer: C 29) Meiotic cell division in animals occurs in the A) body cells; daughter cells B) testes and ovaries; diploid cells C) testes and ovaries; gametes D) body cells; parent cells

and results in the production of

Answer: C 30) Which type of eukaryotic cell contains two types of each chromosome? A) A diploid cell B) A haploid cell C) A gamete D) A meiotically produced cell Answer: A 31) Alternative forms of a gene (such as those responsible for eye color) are called A) cyclins. B) sister chromatids. C) receptors. D) alleles. E) telomeres. Answer: D

32) Which of the following distinguishes prophase 1 of meiosis from prophase of mitosis? A) Spindle forms. B) Homologous chromosomes pair up. C) Nuclear membrane breaks down. D) Chromosomesbecomevisible. Answer: B 33) At the beginning of prophase I, a total of molecules of DNA are contained in a developing human sperm cell. A) 92 B) 23 C) half as many (as compared to somatic cells) D) twice as many (as compared to mature sperm) E) 46 Answer: A 34) During meiosis II A) homologous chromosomes separate. B) sister chromatids of each chromosome are separated from each other. C) cytokinesis results in the formation of a total of two cells. D) homologous chromosomes synapse. E) sister chromatids exchange parts. Answer: B 35) Synapsis and crossing over occurduring A) anaphase I. B) telophase II. C) prophase I. D) metaphase II. E) prophase II. Answer: C 36) In comparing mitosis and meiosis, which of the following statements is TRUE? A) Meiosis II resembles mitosis. B) Meiosis I is more like mitosis than is meiosis II. C) Both processes result in fourcells. D) Synapsis occurs in both. E) Chromatids are present only in mitosis. Answer: A 37) Crossing over A) involves nucleoli. B) alters the composition of chromosomes and results in new combinations of alleles being channeled into the daughter cells. C) generally results in synapsis and binary fission. D) involves breakages and exchanges between sister chromatids. E) All of the choices are correct. Answer: E

38) Independent assortment refers to which of the following statements? A) A maternal chromosome may move toward either pole while the paternal homologue moves toward the other. B) The pole that any one chromosome moves toward is completely independent of the movement of the other 45 chromosomes in humans. C) The sperm that fertilizes the egg is selected at random. D) The position where crossing over occurs is random. E) None of the choices is correct. Answer: A 39) Chromatids are A) attached at their centromeres and are identical until crossing over occurs. B) attached at the centriole. C) attached at their centromeres. D) a pair of chromosomes, one from the mother and one from the father. E) identical until crossing over occurs. Answer: A 40) Chiasmata (or chiasma) provide evidence of A) spindle fiber formation. B) meiosis. C) chromosomal aberration. D) crossing over. E) fertilization. Answer: D 41) Sister chromatids are separated from each other during A) metaphase II. B) anaphase I. C) telophase II. D) metaphase I. E) anaphase II. Answer: E 42) Crossing over A) increases variability in gametes. B) prevents genetic recombination. C) occurs between sister chromatids. D) is followed immediately by separation of each of the chromatids. E) results in only one exchange per homologue. Answer: A 43) If a child more strongly resembles one parent's physical traits than the other parent's, the explanation could be due to chromosome movements during A) telophase I. B) anaphase II. C) anaphase I. D) metaphase II. E) prophase II. Answer: C

44) Which of the following does NOT occur in prophase I of meiosis? A) Crossing over B) Condensation of chromatin C) Tetrad formation D) Synapsis E) Cytokinesis Answer: E 45) Anaphase A) is initiated when the newly divided centromeres begin to move apart. B) is the same in mitosis and meiosis I and II. C) involves the lining up of the chromosomes across the equatorial plate. D) results in an unequal distribution of chromosomes to the resulting cells. Answer: A 46) Paired homologous chromosomes are found at the spindle equator during A) metaphase I. B) anaphase II. C) telophase I. D) prophase II. E) metaphase II. Answer: A 47) Major gene reshuffling takes placeduring A) prophase I. B) metaphase II. C) metaphase I. D) anaphase II. E) anaphase I. Answer: A 48) Under favorable conditions, during which phase of meiosis will the chromosomes appear as packets of four chromatids? A) Anaphase I B) Telophase II C) Prophase I D) Metaphase II E) Anaphase II Answer: C 49) Which of the following events does NOT occur in prophase II but does occur in prophase I? A) Crossing over B) Spindle formation C) Crossing over, synapsis, and spindleformation D) Crossing over and synapsis only E) Synapsis Answer: D

50) What is one difference in mitosis and meiosis during anaphase I? A) Chromatids do not separate at the centromere in anaphase I. B) Centromeres do not exist in anaphase I. C) The chromosomes line up at the equator in anaphase I. D) Crossing over occurs only in anaphase of mitosis. Answer: A 51) Which of the following is unique to mitosis and not a part of meiosis? A) Homologous chromosomes behave independently. B) Chromatids are separated during anaphase. C) Homologous chromosomes pair, forming bivalents. D) Homologous chromosomes cross over. Answer: A 52) Which of the following occurs as a result of meiosis? A) Diploid nuclei with unpaired chromosomes are produced from haploid parent nuclei with paired chromosomes. B) Haploid nuclei with paired chromosomes are produced from diploid parent nuclei with unpaired chromosomes. C) Diploid nuclei with paired chromosomes are produced from haploid parent nuclei with unpaired chromosomes. D) Haploid nuclei with unpaired chromosomes are produced from diploid parent nuclei with paired chromosomes. Answer: D 53) How many total daughter cells are produced from each parent cell as a result of meiosis? A) One B) Two C) Millions D) Four Answer: D 54) How many total haploid cells are produced by one diploid cell during meiosis? A) 2 B) 4 C) 1 D) 8 million Answer: B 55) Which of the following does NOT produce variation? A) Crossing over B) Sexual reproduction C) Genetic recombination of alleles D) Asexual reproduction E) Random alignment of chromosomes during meiosis Answer: D

56) Crossing over is one of the most important events in meiosis because A) homologous chromosomes must be separated into different daughter cells. B) it produces new arrays of alleles on chromosomes. C) homologous chromatids must be separated into different daughter cells. D) the number of chromosomes allotted to each daughter cell must be halved. E) All of the choices are correct. Answer: E 57) The diploid number of chromosomes on a human skin cell is 46. What is the number of chromosomes found in a human egg cell? A) 12.5 B) 184 C) 23 D) 92 E) 46 Answer: C 58) The diploid number of chromosomes in mammals is always A) an even number. B) 46. C) an odd number. D) 23. E) 2. Answer: A 59) Which of the following does NOT provide new genetic combinations? A) Crossing over B) Random fertilization C) Cytokinesis D) Independent assortment Answer: C 60) Which of the following occurs during meiosis? A) Haploid nuclei with paired chromosomes are produced from diploid parent nuclei with unpaired chromosomes. B) Haploid nuclei with unpaired chromosomes are produced from diploid parent nuclei with paired chromosomes. C) Diploid nuclei with unpaired chromosomes are produced from haploid parent nuclei with paired chromosomes. D) Diploid nuclei with paired chromosomes are produced from haploid parent nuclei with unpaired chromosomes. Answer: B 61) In eukaryotes, gametes are producedby A) budding. B) prokaryotic fission. C) mitosis. D) meiosis. Answer: D

62) How many daughter cells are produced from each parent cell during meiosis? A) Two B) Four C) One D) Millions Answer: B 63) When gametes fuse during fertilization, a(n) A) haploid individual B) sperm C) egg D) zygote

is produced.

Answer: D 64) During meiosis, maternal, and paternal chromosomes can exchange genetic material at sites called A) chromatids. B) centrioles. C) chiasmata. D) centromeres. Answer: C 65) Chiasmata are the locations of A) meiosis. B) crossing over. C) sister chromatid attachment. D) mitosis. Answer: B 66) In a haploid daughter cell produced by meiosis, the homologous chromosomes have A) separated. B) mutated. C) multiplied. D) remained attached. Answer: A 67) How many haploid cells are produced by one diploid cell during meiosis? A) 8 million B) One C) Two D) Four Answer: D 68) What is a major difference between mitosis and meiosis? A) Meiosis produces two daughter cells instead of the four daughter cells produced in mitosis. B) Mitosis produces daughter cells, whereas meiosis produces parent cells. C) Meiosis produces haploid cells, whereas mitosis produces diploid cells. D) Meiosis produces genetically identical daughter cells, whereas mitosis produces genetically variable daughter cells. Answer: C

69) How does anaphase of mitosis differ from anaphase I ofmeiosis? A) Sister chromatids do not separate in mitosis, but in anaphase I of meiosis, sister chromosomes do separate. B) In anaphase of mitosis, homologous chromosomes separate, but in anaphase I of meiosis, sister chromatids separate. C) In anaphase of mitosis, sister chromatids separate, but in anaphase I of meiosis, homologous chromosomes separate. D) In anaphase of mitosis, sister chromatids join together, but in anaphase I of meiosis, homologous chromosomes join together. Answer: C 70) In meiosis, sister chromatids separateduring A) cytokinesis. B) prophase I. C) anaphase II. D) prophase II. E) anaphase I. Answer: C 71) During meiosis, the cytokinesis that follows telophase II results in A) four haploid cells. B) two diploid cells. C) two haploid cells. D) four diploid cells. Answer: A 72) In the alternation of generations life cycle, adults may be A) diploid only. B) haploid or diploid. C) haploid only. D) neither haploid nor diploid. Answer: B 73) In flowering plants, pollen representsthe A) zygote. B) diploid stage. C) haploid stage. Answer: C 74) Which of the following cell cycles is represented by ferns and other plants? A) Diploid life cycle B) Alternation of generations C) Haploid life cycle Answer: B 75) Which of the following cell cycles is represented by birds? A) Haploid life cycle B) Alternation of generations C) Diploid life cycle Answer: C

76) All of the following are expected to result in genetic variation among offspring EXCEPT A) crossing over. B) mutations. C) prokaryotic fission. D) random assortmentof parental chromosomes. Answer: C 77) A duplicated chromosome consists of two sister chromatids. A) True B) False Answer: A 78) Sister chromatids are also referred to as homologues or homologous chromosomes. A) True B) False Answer: B 79) Mutations may be detrimental, beneficial, or neutral to the cell or organism in which they occur. A) True B) False Answer: A 80) Crossing over takes place between sister chromatids during prophase I of meiosis I. A) True B) False Answer: B 81) A couple already has 9 children, and they are all girls. If they decide to have a 10th child, it has a 50% chance that it will be male and a 50% chance that it will be female. A) True B) False Answer: A SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 82) The complete set of chromosomes from a single cell is its

Answer: karyotype 83) If a cell contains only one member of each pair of homologues, it referred to as

Answer: haploid 84) The mutual exchange of DNA between maternal and paternal chromosomes at chiasmata is called

Answer: crossingover 85) Sperm and egg fuse to form a diploid fertilized egg, called a

Answer: zygote 86) Occasional errors occur during meiosis, resulting in gametes that have too many or too few chromosomes. Such errors in meiosis, called , can affect the number of sex chromosomes or autosomes in a gamete Answer: nondisjunction

87) About 1 in every 2,500 female babies has only one X chromosome, a condition known as

syndrome.

Answer: Turner 88) About 1 in every 1,000 women has three X chromosomes, a condition known as

Answer: trisomy 89) About 1 in every 500 to 1,000 males is born with two X chromosomes and one Y chromosome, a condition known as syndrome. Answer: Klinefelter 90) About 1 male in 1,000 is born with two Y chromosomes and one X chromosome, a condition known as syndrome. Answer: Jacob 91) An extra copy of chromosome 21, a condition called syndrome, occurs in about 1 of every 700 births, although this rate varies tremendously with the age of the parents. Answer: Down 92) Errors inmeiosis, called

, can affect the number of sex chromosomes or autosomes in a gamete.

Answer: nondisjunction 93) Trisomy is a mutation that results in a cell having an extra

Answer: chromosome 94) How does sexual reproduction produce genetic variability? Answer: Eukaryotic cells typically contain pairs of chromosomes, called homologues, that carry the same genes with similar, although usually not identical, nucleotide sequences. These alternative forms of a gene are called alleles. Cells containing paired homologous chromosomes are called diploid. Cells with only a single copy of each type of chromosome are called haploid. 95) How does meiotic cell division produce genetically variable, haploid cells? Answer: Meiotic cell division (meiosis followed by cytokinesis) separates homologous chromosomes and produces haploid cells with only one homologue from each pair. During interphase before meiosis, chromosomes are duplicated. The cell then undergoes two specialized divisions-meiosis I and meiosis II-to produce four haploid daughtercells. 96) How do meiosis and union of gametes produce genetically variable offspring? Answer: The random shuffling of homologous maternal and paternal chromosomes during meiosis I creates new chromosome combinations. Crossing over also creates new allele combinations on chromosomes. Consequently, a parent probably never produces any gametes that are completely identical. The fusion of two genetically unique gametes adds further genetic variability to the offspring. 97) Mitosis of a haploid cell, a diploid cell, or both, results in the growth of multicellular bodies. Answer: Most eukaryotic life cycles have three parts: (1) Sexual reproduction combines haploid gametes to form a diploid cell. (2) At some point in the life cycle, diploid cells undergo meiotic cell division to produce haploid cells. (3) Mitosis of a haploid cell, a diploid cell, or both, results in the growth of multicellular bodies.

98) How do errors in meiosis cause human genetic disorders? Answer: Errors in meiosis (called nondisjunction) can result in gametes with abnormal numbers of sex chromosomes or autosomes. Many people with abnormal numbers of sex chromosomes have distinguishing physical characteristics, and some have difficulty reproducing. Abnormal numbers of autosomes typically lead to spontaneous abortion early in pregnancy. In rare instances, the fetus may survive to birth, but mental or physical deficiencies always occur. The likelihood of abnormal numbers of chromosomes increases with increasing age of the mother and, to a lesser extent, the father. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 99) What is the name of the figure shown below that depicts the staining and photographing of an entire set of duplicated, condensed chromosomes from a single cell?

A) Karyogram B) Pap smear C) Cytosmear D) Cell smear E) Karyotype Answer: E

100) What is the name of the process depicted below that shows the life cycle of the typical plant?

A) Alternation of genomes B) Mitosis and meiosis C) Meiosis D) Alternation of generations E) Mitosis Answer: D 101) A diploid somatic ("body") cell has 2n = 20 chromosomes. At the end of mitosis, each daughter cell would have chromosomes. At the end of meiosis I, each daughter cell would have chromosomes. Atthe end of meiosis II, each daughter cell would have chromosomes. A) 10, 10, 10 B) 20, 20, 10 C) 20, 20, 20 D) 20, 10, 10 Answer: D

SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 102) For the question below, suppose that the somatic cells of humanoid X contain a total of 4 chromosomes [2N = 4] (or 2 pairs of chromosomes, [N = 2]). How many chromatids and chromosomes are present at the following stages of MEIOSIS? Answers should be filled in for the blank spaces in the table below. Stage

# of CHROMATIDS

# of CHROMOSOMES

Anaphase I of MEIOSIS Anaphase II of MEIOSIS Gamete (sperm of egg) Prophase I of MEIOSIS Prophase II of MEIOSIS Answer: See table below. Stage

# of CHROMATIDS

# of CHROMOSOMES

Anaphase I of MEIOSIS

Anaphase II of MEIOSIS

Gamete (sperm of egg)

Prophase I of MEIOSIS

Prophase II of MEIOSIS

103) In the karyotype of a person with Down syndrome, or trisomy 21, an extra copy of chromosome 21 is apparent. This abnormality affects roughly 1 of every 700 children born and is the most common serious birth defect in the United States. People affected by Down syndrome often have mental retardation and shortened life spans. Based on this scenario and your understanding of meiosis, what is the most likely explanation for the extra chromosome in people with Downsyndrome? Answer: A failure of one pair of homologous chromosomes to separate during meiosis I could have resulted in an extra chromosome 21 being incorporated into a parental gamete. Then the extra chromosome would be inherited along with the normal maternal and paternal copies of chromosome 21. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 104) The ant Myrmecia pilosula has the smallest number of chromosomes possible in a eukaryote: females possess only one pair of chromosomes, and males have only one chromosome! Put another way, female M. pilosula can be described as having the haploid condition n = 1 and the diploid condition 2n = 2. Based on this scenario as well as your knowledge of gamete formation, a female M. pilosula can produce gametes with different sets of chromosomes. A) eight B) four C) two D) millions Answer: C

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Gregor Mendel concluded that each pea has two units for each trait, and each gamete contains one unit. Mendel's "units" are now called A) chromosomes. B) characters. C) transcription factors. D) genes. Answer: D 2) Peas were a good organism of choice for Mendel because A) they cannot cross-fertilize. B) they cannot self-fertilize. C) the traits were difficult tovisualize. D) he could study one trait at a time. Answer: D 3) What is the ratio of phenotypes in the offspring produced by the cross Aa × Aa? Assume complete dominance for the trait. A) 100% recessive B) 75% dominant:25% recessive C) 25% dominant:75% recessive D) 50% dominant:50% recessive E) 100% dominance Answer: B 4) If the allele for inflated pea pods (I) is dominant to the allele for constricted pods (i), then the cross Ii xii is expected to produce A) all peas with inflated pods. B) all peas with constricted pods. C) 3/4 with inflated and 1/4 with constricted pods. D) 3/4 with constricted and 1/4 with inflated pods. E) half with inflated and half with constricted pods. Answer: E 5) According to the law ofsegregation A) pairs of alleles fuse during the formation of gametes. B) the sex chromosomes of males and females differ. C) pairs of alleles on homologous chromosomes separate during the formation of gametes. D) each individual carries a single copy of each "factor." E) there is an independent assortment of nonhomologous chromosomes during meiosis. Answer: C 6) According to the law of segregation, in an organism with the genotype Aa A) all of the gametes get the A allele. B) three-quarters of the gametes get the A allele and one-quarter get the a allele. C) all of the gametes get the a allele. D) one-quarter of the gametes get the A allele and three-quarters get the a allele. E) one-half of the gametes get the A allele and one-half get the a allele. Answer: E

7) A recessive allele is one A) that must be lethal in the homozygous condition. B) whose effect is masked when paired with a dominant allele. C) that is not expressed as strongly as a dominant allele. D) that appears only in aheterozygote. E) that produces no effect when present in the homozygous condition. Answer: B 8) Which of the following statements about genotypes and phenotypes is TRUE? A) Individuals with the same genotype might have different phenotypes. B) Matings between individuals with dominant phenotypes cannot produce offspring with recessive phenotypes. C) Individuals with the same phenotype might have different genotypes. D) Matings between individuals with recessive phenotypes produce offspring with dominant phenotypes. Answer: C 9) If, in a heterozygous individual, only one allele is expressed in the phenotype, that allele is A) normal. B) potent. C) recessive. D) dominant. E) haploid. Answer: D 10) The physical manifestation of an organism's genes is its A) environment. B) genetic code. C) number of chromosomes. D) phenotype. E) genotype. Answer: D 11) When the two gametes that fuse to form a zygote contain different alleles of a given gene, the offspring is A) heterozygous. B) haploid. C) homozygous. D) abnormal. E) a newspecies. Answer: A 12) If we cross two pea plants, each heterozygous for yellow seed color genes, the expected ratio of yellow:green among the offspring will be A) 25% yellow:75%green. B) 75% yellow:25%green. C) 100% yellow. D) 50% yellow:50% green. E) 100% green. Answer: B

13) What type of allele produces its effects in only homozygous individuals? A) Diploid B) Haploid C) Recessive D) Dominant Answer: C 14) When alleles on a pair of homologous chromosomes move into different gametes during meiosis, this demonstrates A) dominance. B) fertilization. C) segregation. D) crossing over. E) recessive inheritance. Answer: C 15) Round pea shape (R) is dominant over wrinkled pea shape (r). If a round pea has a wrinkled parent, the round pea is A) haploid. B) recessive. C) Rr. D) rr. E) RR. Answer: C 16) Mendel's law of segregation states that A) each gamete receives a full complement of chromosomes. B) genes in the same chromosome must stay together. C) genes end up in their respective gametes by chance. D) members of a pair of alleles on homologous chromosomes move away from each other during gamete formation. E) there may be alternative forms of the same gene. Answer: D 17) When Mendel used true-breeding white flowers and true-breeding purple flowers as the parental generation, what were the results? (Purple flower is dominant over white.) A) All of the offspring had white flowers. B) All of the offspring had purple flowers. C) Three-quarters of the flowers produced were white and one-quarter were purple. D) Three-quarters of the flowers produced were purple and one-quarter were white. E) One-half of the flowers produced were white and one-half werepurple. Answer: B 18) The genetic makeup of an individual is the A) sex cell. B) mutation. C) phenotype. D) gene pool. E) genotype. Answer: E

19) The results of a test cross reveal that all the offspring resemble the parent being tested. This parent must be A) haploid. B) recessive. C) heterozygous. D) self-pollinated. E) homozygous. Answer: E 20) A Mendelian test cross is used to determine whether A) an individual is homozygous or heterozygous. B) an allele is dominant orrecessive. C) the flowers are purple orwhite. D) the genotype or phenotype is more important. E) segregation or independent assortment is occurring. Answer: A 21) Yellow-seeded pea plants may be homozygous or heterozygous. To find out which, cross the plants with A) true-breeding yellow-seeded plants. B) heterozygous green-seeded plants. C) heterozygous yellow-seeded plants. D) true-breeding green-seeded plants. E) the same genotype. Answer: D 22) In a test cross, what percentage of the offspring will have the same phenotype as the tested parent if the parent to be tested is homozygous? A) 100% B) 75% C) 50% D) 0% E) 25% Answer: A 23) What is the genotype of a dominant individual if, when selfed, some of its offspring show the recessive phenotype? A) dd B) Dd C) Either DD or Dd D) DD Answer: B 24) Crossing smooth-seeded pea plants with wrinkled-seeded pea plants resulted in progeny that all had smooth seeds. This indicates that the wrinkled-seed trait is A) codominant only. B) codominant and recessive. C) dominant only. D) recessive only. E) codominant and dominant. Answer: D

25) A pea plant with red flowers is test crossed; half of the resulting progeny have red flowers, whereas the other half have white flowers. The genotype of the test-crossed parent was A) Rr. B) either RR or Rr. C) rr. D) RR. Answer: A 26) Albinism results from a recessive allele. Which of the following describes the expected offspring from a normally pigmented male (who had an albino father) and an albino wife? A) 75% normal; 25% albino B) 50% normal; 50% albino C) All albino D) 75% albino; 25% normal E) All normal Answer: B 27) In garden peas, the allele for tall plants is dominant over the allele for short plants. Imagine that a true-breeding tall plant is crossed with a short plant. Then one of their offspring is test crossed. Out of 20 offspring resulting from the test cross, about how many should be tall? A) 10 B) 5 C) 20 D) 0 E) 15 Answer: A 28) In crossing a homozygous recessive with a heterozygote, what is the chance of getting a homozygous recessive phenotype in the F1 generation? A) 75% B) 25% C) 0% D) 50% E) 100% Answer: D 29) If two parents are carriers of albinism (an autosomal recessive trait), what is the chance that their fourth child will have a homozygous dominantgenotype? A) 25% B) 0% C) 100% D) 50% E) 75% Answer: A

30) All of the following combinations are possible in the gametes of an organism that is AaBb EXCEPT A) Ab. B) aB. C) ab. D) AB. E) aa. Answer: E 31) Imagine that a newly discovered species of fish normally has three eyes (E), but the rare mutation (e) causes "diopthalmic" fish with two eyes to be born. In addition, eye color in these fish is inherited similarly to humans, with black eyes (B) being dominant to blue (b). Assuming these two genes are carried on separate chromosomes, what must the genotypes of two black-eyed, three-eyed parents be if they have a blue-eyed, diopthalmic son? A) EEBB and eebb B) eeBB and EEbb C) Both eebb D) Both EeBb Answer: D 32) Suppose you cross a pea plant with yellow, smooth seeds with one that has green, wrinkled seeds. You examine the seeds of 967 offspring and find that some have yellow, smooth seeds and some have yellow, wrinkled seeds, but no green seeds of either type show up. What is the genotype of the yellow-seeded parent? (Y = yellow, y = green; S = smooth, s = wrinkled) A) YySs B) YYSs C) YYss D) YYSS E) YySS Answer: B 33) In pea plants, tall plants are dominant over short, and green pods are dominant over yellow. If you crossed true-breeding tall, green-podded plants with true-breeding short, yellow-podded plants, and then crossed the F1 individuals among themselves, what proportion of the F2 offspring would you expect to be tall and yellow-podded? A) 1/4 B) 3/16 C) 9/16 D) 1/16 E) 3/4 Answer: B 34) If you cross pea plants that are both heterozygous for purple flowers and yellow seeds (PpYy), and you examine 800 offspring for flower and seed color, about how many do you expect to have white flowers and green seeds? A) 50 B) All of them (800) C) 150 D) None of them E) 450 Answer: A

35) Although the law of independent assortment is generally applicable, when two loci are located physically close to each other on the same chromosome, the phenotypes of the offspring sometimes do not fit the phenotypes predicted. This is due to A) chromosome exchange. B) chromatid abnormalities. C) translation. D) linkage. E) inversions. Answer: D 36) Imagine that you self-pollinate heterozygous purple-flowered, long-pollened pea plants and get mostly purple-flowered, long-pollened plants and white-flowered, short-pollened plants, with afew purple-flowered, short-pollened or white-flowered, long-pollened plants. What is the most likely explanation? A) The genes for flower color and pollen length are linked. B) This is a normal random variation from the expected ratio for independent assortment. C) Long pollen is often lethal, so few plants with long pollen survive to adulthood. D) The purple allele influences pollen to become shorter. E) The gene for flower color is on a sex chromosome. Answer: A 37) Which of the following is TRUE of genes that are physically located close to each other on the same chromosome? A) They are not linked. B) They tend to not be inherited together. C) They are linked and tend to be inherited together. D) They will be expressed differently in males than in females. Answer: C 38) When genes are linked, a few of the recombinant genotypes still occur in the offspring because of A) crossing over. B) independent assortment. C) natural selection. D) mutation. E) linkage. Answer: A 39) Imagine you do a test cross between a purple-flowered pea plant having serrated leaves (both dominant traits) and a white-flowered pea plant having smooth edges. If the purple-flowered plant is heterozygous for both traits, the expected ratio in the offspring is 1 purple-serrated:1 purple-smooth:1 white-serrated:1 white-smooth. Instead, you see 7 purple-serrated:1 purple-smooth:1 white-serrated:7 white-smooth. What is the explanation of this ratio? A) The genes are sex-linked and inherited by incomplete dominance. B) There is incomplete dominance. C) The genes are linked. D) There has been a mutation during the cross. Answer: C

40) What would be TRUE if linkage of two genes was complete? A) The genes would assort independently. B) All possible combinations of alleles in the offspring would be produced. C) Crossing over between the two genes would rarely occur. D) All possible combinations of alleles in the gametes would be produced. Answer: C 41) A human sperm cell possesses autosomes and A) either an X or a Y chromosome. B) an X chromosome always. C) exactly the same genetic information as a body cell. D) a Y chromosome always. E) both an X and a Y chromosome. Answer: A 42) In humans, the sex of the offspring is determined by the A) autosomes carried by the egg cell. B) autosomes carried by the spermcell. C) cytoplasm carried by the egg cell. D) sex chromosome carried by the sperm cell. E) sex chromosome carried by the egg cell. Answer: D 43) Which of the following is a sex-linked recessive condition? A) Cystic fibrosis B) Down syndrome C) Sickle-cell anemia D) Hemophilia E) Albinism Answer: D 44) Traits controlled by sex-linked recessive genes are expressed more often in males because A) males always carry two copies of these genes. B) all male offspring of a female carrier get the gene. C) the male has only one gene for the trait. D) males inherit these genes from their fathers more often than their mothers. E) males get more doses of the recessive gene than do females. Answer: C 45) A recessive allele on the X chromosome causes color deficiency. A noncolor-deficient woman (whose father is color deficient) marries a color-deficient man. If they have a son, what is the chance that he will be color deficient? A) 0% B) 50% C) 75% D) 25% E) 100% Answer: B

46) Hemophilia is a sex-linked recessive gene that causes a blood disorder. What are the chances that the daughter of a normal man and a heterozygous woman will have hemophilia? A) 25% B) 0% C) 75% D) 100% E) 50% Answer: B 47) A recessive allele on the X chromosome causes color deficiency. A color-deficient boy has a mother with normal vision and a color-deficient father. From which parent did he get the color-deficiency gene? A) Mother B) Father C) Either mother or father Answer: A 48) A man who carries a harmful sex-linked (on the X chromosome) gene will pass the gene on to A) all of his sons. B) half of his daughters. C) all of his daughters. D) half of his sons. E) all of his sons anddaughters. Answer: C 49) Color deficiency is more common in men than in women because A) men have only one Xchromosome. B) the gene is located on the Y chromosome. C) crossing over occurs only inwomen. D) women cannot inherit the gene from their fathers. E) men get more copies of the gene than do women. Answer: A 50) An individual who is a carrier for a sex-linked trait such as hemophilia A) shows the dominant phenotype. B) is always female. C) is homozygous for the recessivecondition. D) cannot pass the gene on to his or her daughters. Answer: B 51) A type of muscular dystrophy shows sex-linked recessive inheritance. Affected persons usually die by the age of 20. Suppose that a boy with the disease lives long enough to marry a woman heterozygous for the trait. If they have a son, what is the probability that he will have the disease? A) 0% B) 50% C) 25% D) 100% E) 75% Answer: B

52) Two parents with normal vision have two sons, one color deficient and one with normal vision. If this couple then has six daughters, can you predict what percentage of the daughters will have normal color vision? A) 100% B) 75% C) 25% D) 50% E) 0% Answer: A 53) Blood typing is often used as evidence in paternity cases in court. In one case, the mother had blood type B and the child had blood type O. Which of the following blood types could the father NOT have? A) O B) A C) B D) AB Answer: D 54) Codominance occurs when A) offspring exhibit several different phenotypic expressions of a single trait. B) expression of two different alleles alternates from one generation to the next. C) both of the alleles in a heterozygote are equally expressed phenotypically in an individual. D) a heterozygote expresses an intermediate phenotype. Answer: C 55) When the expression of a trait is influenced by the action of many genes, the pattern of inheritance is called A) polygenic inheritance. B) incomplete dominance. C) multiple alleles. D) discontinuous variation. E) complete dominance. Answer: A 56) Human eye color is the result of A) simple dominance. B) codominance. C) genes and environmental effects. D) sex-linked recessive inheritance. E) polygenicinheritance. Answer: E 57) Imagine that smurfs live in widely separated groups and rarely interbreed, so geneticists know very little about them. On one occasion, two smurfs from different groups did mate. A big-footed, white smurf mated with a small-footed, blue smurf. Three offspring resulted: one big-footed and blue and two small-footed and blue. Which statement about the inheritance of color in smurfs is most likely to be correct? A) White is dominant to blue. B) Blue is dominant to white. C) White and blue arecodominant. Answer: B

58) In Mendel's experiments, if the gene for tall (T1) plants was incompletely dominant over the gene for short (T2) plants, what would be the result of crossing two T1T2 plants? A) 50% tall, 25% intermediate, and 25% short B) 25% tall, 50% intermediate, and 25% short C) All the offspring would beintermediate. D) 25% tall, 25% intermediate, and 50% short E) All the offspring would be tall. Answer: B 59) Human skin color is the result of A) codominance. B) polygenic inheritance. C) simple dominance. D) sex-linked recessive inheritance. E) one pair of genes showing incomplete dominance. Answer: B 60) If an individual who is homozygous for type B blood marries a heterozygous type A individual, what is the chance that their first child will have type AB blood? A) 100% B) 75% C) 25% D) 0% E) 50% Answer: E 61) All of the following are true regarding pedigree analysis EXCEPT that it A) documents the transmission of a genetic characteristic over two or more generations. B) reveals whether a trait is dominant or recessive. C) is exclusively used to study the patterns of inheritance in dogs. D) can incorporate molecular biology techniques. Answer: C

62) Sickle-cell anemia is caused by a A) recessive autosomal gene. B) simple dominant gene. C) combined interaction of several genes. recessive sex-linked gene. E) dominant autosomal gene. Answer: A 63) Which of the following conditions may cause infertility in a human? A) XX B) XXX C) XY D) XYY E) XXY Answer: E

64) Which of the following is the most common chromosome disorder among live-born infants? A) Trisomy X B) Turner syndrome C) Down syndrome D) Klinefelter syndrome Answer: C 65) Autosomal nondisjunction can result in A) Klinefelter syndrome. B) XYY males. C) Down syndrome. D) trisomy X. E) Turner syndrome. Answer: C 66) The failure of chromosomes to segregate properly during meiosis is called A) inversion. B) replication. C) translocation. D) independent assortment. E) nondisjunction. Answer: E 67) Which disorder is characterized by an abnormal number of autosomes? A) Turner syndrome B) Klinefelter syndrome C) Trisomy X D) XYY syndrome E) Down syndrome Answer: E 68) For which disorder can those affected be male or female? A) Turner syndrome B) Klinefelter syndrome C) Trisomy X D) XYY syndrome E) Down syndrome Answer: E 69) Which disorder is characterized by the individual having a normal number of sex chromosomes? A) Turner syndrome B) Klinefelter syndrome C) Trisomy X D) XYY syndrome E) Down syndrome Answer: E

70) Which disorder is more common among the babies of older mothers? A) Turner syndrome B) Klinefelter syndrome C) Trisomy X D) XYY syndrome E) Down syndrome Answer: E 71) Which disorder is the most common chromosome anomaly among newborns? A) Turner syndrome B) Klinefelter syndrome C) Trisomy X D) XYY syndrome E) Down syndrome Answer: E 72) A disorder caused by nondisjunction of chromosome 21, resulting in a trisomy 21 child, is A) color deficiency. B) Down syndrome. C) cystic fibrosis. D) hemophilia. Answer: B 73) What is the difference between phenotype and genotype? A) Phenotype is when both alleles are the same and genotype is when the alleles are different. B) Phenotype is the alleles that are hidden and genotype is the alleles that are expressed. C) Genotype is the physical expression of a trait and phenotype is the combination of alleles carried by the organism. D) Phenotype is the physical expression of a trait and genotype is the combination of alleles carried by the organism. Answer: D 74) A child is born with dwarfism (tt). His parents are of normal height. Which of the following must be TRUE of the parents? A) They are both heterozygous dwarf. B) They are both homozygous dominanttall. C) They are both homozygous recessivedwarf. D) They are both heterozygous tall. Answer: D 75) Sickle-cell anemia is caused by a recessive mutation in the hemoglobin gene. However, heterozygote individuals also show a small percentage of sickled red blood cells. What type of inheritance pattern is this an example of? A) Sex linked B) Incomplete dominance C) Chromosomal nondisjunction D) Polygenic inheritance Answer: B

76) What is the reason for the prevalence of the sickle-cell allele in African populations? A) Sickled cells help prevent vitamin A deficiency among African populations. B) Sickled cells are better able to clotblood. C) Heterozygotes have some resistance to the parasite that causes malaria. D) African populations tend to be at higher altitudes, and sickled cells better bind oxygen in these environments. Answer: C 77) A woman with blood type AB and a man with blood type O have three children, one of whom is adopted. The blood types of the children are A, B, and O. What is the blood type of the adopted child? A) B B) A C) O D) Not enough information is provided to answer this question. Answer: C 78) Yellow pea color is dominant over green pea color, despite the observation that most store-bought, edible peas are green. A) True B) False Answer: A 79) Only males can express sex-linkedtraits. A) True B) False Answer: B 80) Females always inherit sex-linked traits from their mothers. A) True B) False Answer: B 81) Sex-linked traits affect onlysexual characteristics. A) True B) False Answer: B 82) Human females who receive sex-linked genes always express them. A) True B) False Answer: B SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 83) A(n) is a portion of DNA that resides at a particular locus or site on a chromosome and encodes a particular function. Answer: gene (or allele) 84) The location of a gene on a chromosome is called a(n) Answer: locus

85) The human genome contains 46 chromosomes. There are 22 pairs of pair of (type of chromosome).

(type of chromosome) and one

Answer: autosomes; sex chromosomes 86) The blood types of humans are an example of

Answer: codominance (or multiple alleles) 87) The wavy hair in children of straight-haired and curly-haired parents resultsfroma pattern of inheritance called . Answer: incomplete dominance 88) In human blood types, the alleles for A and B are said to be present in an individual.

because they are both expressed equally if

Answer: codominant 89) A female who is heterozygous for a recessive, sex-linked trait is a(n)

for that trait.

Answer: carrier 90) For independent assortment of alleles for two different genes to occur, where must the genes be located? Answer: The genes must be on different chromosomes. 91) Describe where in the process of meiosis independent assortment of genes occurs. Answer: Homologous pairs of chromosomes align randomly along the metaphase plate during metaphase I and then separate during anaphase I. 92) What are the possible gamete genotypes of an organism that has the genotype HhTt if the two genes are located on separate chromosomes and therefore not linked? Answer: HT, Ht, hT, and ht 93) What pattern of inheritance "breaks the law" of independent assortment? Answer: Alleles that are close together on the same chromosome tend to be inherited together. This is called gene linkage. 94) What must occur to result in linked genes not being inherited together? Answer: Chromosomes recombine during crossing over in prophase I of meiosis.

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 95) Based on this figure, what is the genotype of an individual pea plant that is homozygous for green pod and constricted pod and is 6 feet tall? (Assume that green and yellow pods are indicated by G and g, inflated and constricted pods by I and i, and height by T and t.)

A) GGiiTT B) ggiitt C) ggiiTT D) GgIiTt E) GGIITT Answer: A

96) Based on this pedigree, which individual was a carrier for hemophilia but did not suffer from the disease? A) Irene (generation IV) B) Alexandra of Denmark (generation III) C) Victoria, Princess of Saxe-Coburg (generation I) D) Gonzalo (generation V) E) Frederick(generation IV) Answer: A 97) Hemophilia is a genetic disease that has plagued the royal houses of Europe since the time of Queen Victoria, who was a carrier. Her granddaughter, Alexandra, married Nicholas II, the last czar of imperial Russia. Alexandra was a carrier for hemophilia, but Nicholas was normal. Their son, Alexis, was afflicted with the disease. Based on this scenario, it is most likely that A) all four sisters were carriers of the hemophilia gene. B) none of the four sisters carried the hemophilia gene. C) Alexis inherited the hemophilia gene from Nicholas II. D) each of the sisters had a 50% chance of being a carrier of the gene. E) at least one of the sisters had hemophilia. Answer: D 98) In people, a dimpled chin is an autosomal dominant trait. Many famous celebrities, such as John Travolta and Michael and Kirk Douglas, have this condition. Assume that the wrestler and actor Hulk Hogan is homozygous for the dimpled chin, and he married a woman with a round chin. They had two children, Brooke and Nick. What is the probability that their children will show the trait? A) 75% B) 100% C) 0% D) 50% E) 25% Answer: B

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) The hereditary material present in all cells is A) protein. B) S-strain. C) DNA. D) RNA. E) R-strain. Answer: C 2) What was the most significant conclusion of Griffith's experiments with pneumonia in mice? A) There is a substance present in dead bacteria that can cause a heritable change in living bacteria. B) Heat destroys the hereditary material. C) Mice exposed to the S-strain bacterium became resistant to the R-strain bacterium. D) The genetic material was definitively proven to be DNA. E) S-strain bacteria can causepneumonia. Answer: A 3) What is the relationship among DNA, a gene, and a chromosome? A) A gene is composed of DNA, but it has no relationship to a chromosome. B) A chromosome contains hundreds of genes, which are composed of protein. C) A gene contains hundreds of chromosomes, which are composed of DNA. D) A gene contains hundreds of chromosomes, which are composed of protein. E) A chromosome contains hundreds of genes, which are composed of DNA. Answer: E 4) In Griffith's experiments, what happened when heat-killed S-strain bacteria were injected into a mouse along with live R-strain bacteria? A) DNA from the heat-killed S-strain was taken up by the live R-strain, converting them to S-strain and killing the mouse. B) RNA from the heat-killed S-strain was translated into proteins that killed the mouse. C) DNA from the live R-strain was taken up by the heat-killed S-strain, converting them to R-strain and killing the mouse. D) Proteins released from the heat-killed S-strain killed the mouse. Answer: A 5) When Griffith experimented with two types of Streptococcus pneumoniae, he found that if the A) non-deadly strain was mixed with the heat-killed, deadly strain before injection, the mice died. B) non-deadly strain was mixed with the heat-killed, deadly strain before injection, the mice lived. C) deadly strain was heat-killed before injection, the mice died. D) non-deadly strain was mixed with the heat-killed, non-deadly strain before injection, the mice died. Answer: A 6) DNA possesses A) only U and T bases. B) A, U, G, and C bases. C) only A and G bases. D) C, T, A, and Gbases. E) only C and T bases. Answer: D

7) If the quantities of the four bases in a DNA molecule are measured, we find that A) A = C and G = T. B) T = A and C = G. C) A = G and C = T. D) no two bases are equal in amount. E) all bases are equal in amount. Answer: B 8) If the DNA of a certain organism has guanine as 30% of its bases, then what percentage of its bases are adenine? A) 30% B) 0% C) 10% D) 20% E) 40% Answer: D 9) All of the following are found in DNAEXCEPT A) a phosphate group. B) a phospholipid group. C) guanine. D) deoxyribose. E) thymine. Answer: B 10) A DNA nucleotide is made up of A) phosphate-deoxyribose-base. B) phospholipid-deoxyribose-base. C) base-phosphate-glucose. D) phosphate-deoxyribose-phosphate-deoxyribose. E) adenine-thymine-guanine-cytosine. Answer: A 11) The 'rule" formulated by Chargaff states that A) A = G and C = T in any molecule of DNA. B) A = C and G = T in any molecule of DNA. C) A = T and G = C in any molecule of DNA. D) A = U and G = C in any molecule of RNA. E) DNA and RNA are made up of the same four nitrogenous bases. Answer: C 12) Hershey and Chase concluded that is the hereditary molecule by examining how radioactively labeled molecules moved between a virus and bacteria. A) protein B) phospholipids C) DNA D) Lipids Answer: C

13) By the early 1950s, many biologists realized that the key to understanding inheritance lay in the structure of A) DNA. B) ribosomes. C) chromosomes. D) protein. E) enzymes. Answer: A 14) The X-ray diffraction pattern for DNA suggested to Wilkins and Franklin all of the following features about DNA EXCEPT A) a DNA molecule has a uniform diameter of 2 nanometers. B) a DNA molecule is helical. C) in a DNA molecule, A pairs with T and G pairs with C. D) the DNA molecule consists of repeating subunits. E) the phosphate-sugar "backbone" of the molecule is on the outside of the DNA helix. Answer: C 15) In DNA, phosphate groups bondto A) adenine. B) pyrimidine bases. C) ribose. D) other phosphate groups. E) deoxyribose. Answer: E 16) The sequence of subunits in the DNA "backbone" is A) -phosphate-sugar-phosphate-sugar-phosphate-sugar-. B) -base-sugar-phosphate-base-sugar-phosphate-. C) -sugar-base-sugar-base-sugar-base-sugar-base-. D) -base-phosphate-sugar-base-phosphate-sugar-. E) -base-phosphate-base-phosphate-base-phosphate-. Answer: A 17) "Chargaff's rule" for base pairing in DNA is that A) the amount of A = the amount of G, and the amount of C = the amount of T. B) A bonds with T, and G bonds with C. C) A bonds with G, and C bonds with T. D) A bonds with C, and G bonds with T. E) the amount of A = the amount of C, and the amount of G = the amount of T. Answer: B 18) Complementary base pairs are held together by A) hydrogen bonds. B) disulfide bonds. C) peptide bonds. D) covalent bonds. E) ionic bonds. Answer: A

19) The two polynucleotide chains in a DNA molecule are attached to each other by A) peptide bonds between amino acids. B) hydrogen bonds between bases. C) covalent bonds between phosphates andsugars. D) covalent bonds between carbon atoms. E) ionic bonds between "R" groups in amino acids. Answer: B 20) In a DNA molecule, base pairing occurs between A) guanine and uracil. B) adenineandthymine. C) adenineandguanine. D) thymine and cytosine. E) adenine and uracil. Answer: B 21) If the DNA sequence is G-C-C-T-A-T in one polynucleotide chain, then the sequence found in the other polynucleotide chain must be A) G-C-C-A-T-A. B) G-C-C-T-A-T. C) A-T-T-C-G-C. D) C-G-G-A-U-A. E) C-G-G-A-T-A. Answer: E 22) Which of the following is TRUE in the Watson-Crick model of DNA? A) Four different types of bases are found in DNA. B) During replication, the phosphate groups are copied but the base sequence is not copied. C) Ribose always bonds to a nitrogenous base. D) Phosphate groups always bond toribose. E) The number of adenines equals the number of guanines. Answer: A 23) In the comparison of a DNA molecule to a twisted ladder, the upright sides of the ladder are A) deoxyribose linked to sulfate. B) deoxyribose linked to phosphate. C) nitrogenous bases linked to phosphate. D) nitrogenous bases linked together. E) hydrogen bonds between bases. Answer: B 24) In the comparison of a DNA molecule to a twisted ladder, the rungs (footholds) of the ladder are A) nitrogenous bases linked to phosphate. B) deoxyribose linked to phosphate. C) the backbones of the molecule. D) deoxyribose linked to sulfate. E) nitrogenous bases linkedtogether. Answer: E

25) Which of the following is NOT true according to Chargaff's base pairing rule? A) A + T = G + C in amount. B) A =T in amount. C) A + G = T + C in amount. D) G = C inamount. Answer: A 26) Which component of a DNA nucleotide could be removed without breaking the polynucleotide chain? A) Deoxyribose B) Phosphate C) Nitrogen base D) Ribose Answer: C 27) It became apparent to Watson and Crick after completing their model that a DNA molecule could carry a vast amount of hereditary information in its A) phosphate-sugar backbone. B) side groups of bases. C) different five-carbon sugars. D) sequence of bases. E) variety of phosphate groups. Answer: D 28) The way DNA stores information is through the A) number B) sequence C) size D) different types

of bases.

Answer: B 29) Regarding the structure of DNA, which of the following is like a spiral staircase? A) Phosphate B) Deoxyribose C) Covalent bonds D) Double helix E) Hydrogen bonds Answer: D 30) Regarding the structure of DNA, which of the following joins deoxyribose to phosphate? A) Ionic bonds B) Covalent bonds C) Phosphate D) Hydrogen bonds E) Double helix Answer: B

31) Regarding the structure of DNA, which of the following joins adenine and thymine and also guanine and cytosine? A) Covalent bonds B) Deoxyribose C) Double helix D) Phosphate E) Hydrogen bonds Answer: E 32) Watson and Crick are credited with the discovery and description of the DNA A) covalent bonds. B) hydrogen bonds. C) deoxyribose sugar. D) double helix. E) phosphate group. Answer: D 33) Regarding the structure of DNA, which of the following is covalently bonded to a nitrogen base? A) Phospholipid B) Phosphate C) Deoxyribose D) Hydrogen bonds E) Ribose Answer: C 34) Regarding the structure of DNA, the units that form the "uprights" (sides) of the DNA ladder and do not attach to the nitrogen bases are A) ribose molecules. B) deoxyribose molecules. C) sulfur-containing bases. D) phosphate molecules. Answer: D 35) How many different kinds of base pairings are in DNA? A) Two B) Hundreds or thousands C) Millions D) Four Answer: A 36) How many different kinds of nucleotides are in DNA? A) Two B) Hundreds or thousands C) Millions D) Four Answer: D

37) How many bases are in the DNA molecule of a typical human chromosome? A) Millions B) Thousands C) Four D) Two Answer: A 38) Which of the following is TRUE regarding the genetic information in the cells of your body? A) Different kinds of body cells contain different genetic information. B) The genetic information in almost all of your body cells is identical. C) The genetic information in your body cells changes in a predictable manner as you grow and develop. D) Each type of body cell contains only the genetic information it needs to be that type of cell. Answer: B 39) When a cell divides, each daughter cell receives A) a nearly perfect copy of the parent cell's genetic information. B) the same amount of genetic information that was in the parent cell, but it has been altered. C) exactly half the genetic information in the parent cell. D) twice the amount of genetic information of the parent cell. Answer: A 40) When DNA polymerase encounters thymine in the parental strand, what does it add to the growing daughter strand? A) Deoxyribose B) Uracil C) Phosphate group D) Adenine Answer: D 41) Semiconservative DNA replication means that A) only half of the DNA is replicated. B) each new DNA molecule has half the DNA from the old one. C) the old DNA is completely broken down. D) A pairs with T and G pairs with C. E) the old DNA remains completely intact. Answer: B 42) All of the following occur during DNA replication EXCEPT A) separation of parental DNA strands. B) synthesis of totally new double-stranded DNA molecules. C) use of parental DNA asa template. D) use of DNA polymerase enzymes. Answer: B 43) When chromosomes replicate A) the two DNA strands separate and each is used as a template for synthesis of a new strand. B) one strand of the DNA is completely replicated first, and then the second strand is replicated. C) the original DNA is distributed to the two daughter cells, with no new DNA synthesized. D) new DNA synthesis occurs in only one location along the entire DNA molecule. Answer: A

44) In one strand of DNA, the nucleotide sequence is 5'-A-T-G-C-3'. The complementary sequence in the other strand must be A) 5'-C-G-T-A-3'. B) 3'-T-A-C-G-5'. C) 5'-A-T-G-C-3'. D) 3'-G-C-A-T-5'. Answer: B 45) Which of the following is NOT involved in the DNA replication process? A) DNA replicase B) DNA helicase C) DNA polymerase D) DNA ligase Answer: A 46) Which of the following is TRUE about the accuracy of DNA replication? A) Many errors are made during DNA replication, but this does not matter because repair enzymes mend the errors. B) Many errors are made during DNA replication, but this does not matter because of the immense size of the DNA molecule. C) DNA polymerase always makes a perfect copy of the original DNA. D) DNA polymerase makes very few errors, so no repair enzymes are needed. E) The few errors made by DNA polymerase are usually corrected by repair enzymes. Answer: E 47) A cell that lacks the ability to make DNA repair enzymes will A) be unable to replicate its DNA. B) be able to correctly replicate its DNA, but it will need more time to do so. C) replicate its DNA as well as a cell with intact repair enzymes. D) replicate its DNA as rapidly as a normal cell, but the resulting DNA will have more errors in it. Answer: D 48) DNA polymerase, before any proofreading by repair enzymes, makes one mistake for about every A) 1 million to 10 million base pairs. B) 100 million to 10 billion base pairs. C) 100 to 1,000 base pairs. D) 1 to 100 base pairs. E) 10,000 to 1 million base pairs. Answer: E 49) After proofreading repair enzymes check the work of DNA polymerase, newly replicated DNA strands contain about one mistake for every A) 100 million to 10 billion base pairs. B) 1 million to 10 million base pairs. C) 10,000 to 1 million base pairs. D) 1 to 100 base pairs. E) 100 to 1,000 basepairs. Answer: A

50) Which of the following is TRUE regarding how the DNA in your body's cells can accumulate mutations? A) Mistakes are never made during DNA replication; they always occur during the G1 phase of interphase. B) Some DNA spontaneously breaks down every second, making the chromosome significantly shorter with every passing day. C) Spontaneous mutation rates are around one in every four nucleotides that are replicated. D) The ultraviolet radiation in sunlight may induce changes in DNA. Answer: D 51) Imagine that a DNA sequence of 5'-A-C-G-T-A-C-G-T-3' is altered to 5'-A-C-G-C-A-C-G-T-3'. This could happen as a result of a(n) A) translocation. B) insertion mutation. C) inversion. D) deletion mutation. E) nucleotide substitution mutation. Answer: E 52) Imaginethata DNAsequence of 5'-A-C-G-T-A-C-G-T-3' is altered to 5'-A-C-G-A-C-G-T-3'. Thiscould happen as a result of a(n) A) translocation. B) inversion. C) deletion mutation. D) insertion mutation. E) nucleotide substitution mutation. Answer: C 53) What two bases in the DNA molecule are double-ringed? A) Guanine and adenine B) Thymine andcytosine C) Thymine and uracil D) Uracil and guanine E) Guanine and cytosine Answer: A 54) Mutations are a source of genetic A) variability B) reproduction C) constancy D) stability

by which evolutionary change is possible.

Answer: A 55) Agents that cause mutations are called mutagens. All of the following are examples of mutagens EXCEPT A) X-rays. B) vitamins. C) ultraviolet radiation. D) cigarette smoke. Answer: B

56) Specific segments of DNA that code for a specific protein are called A) nucleoli. B) chromosomes. C) mutations. D) genes. E) nuclei. Answer: D 57) What determines the function of the gene product? A) The sequences of deoxyribose B) The number of bases C) The sequence of phosphates D) The number of phosphates E) The sequence of bases Answer: E 58)

replication is the process when DNA uses one parental strand and synthesizes a new strand, resulting in each daughter cell having a new and parental DNA strand. A) Redundant B) Conservative C) Semiconservative D) Inversion Answer: C

59) DNA polymerase always moves from on one strand and discontinuous on the other. A) base to phosphor group B) phosphate group to base C) 3' to 5' D) 5' to 3'

along the strand resulting in DNA replication to be continuous

Answer: C 60) A(n) mutation is when one or more nucleotide pairs are lost. A) insertion B) deletion C) nucleotide substitution D) inversion Answer: B 61) In eukaryotic cells, chromosomes are composed of both DNA and proteins. A) True B) False Answer: A 62) Chargaff found that the amounts of the four bases vary from species to species, but the amount of adenine always equals the amount of guanine and the amount of thymine always equals the amount of cytosine. A) True B) False Answer: B

63) The two strands of DNA are held together by hydrogen bonds. A) True B) False Answer: A 64) The number of subunits in a DNA molecule is more important to its function than the sequence of these subunits. A) True B) False Answer: B 65) DNA ligase is important in the replication process because it can join together segments of DNA into a single daughter strand. A) True B) False Answer: A 66) During DNA replication, the continuous daughter strand is the leading strand. A) True B) False Answer: A 67) In semiconservative replication, a DNA molecule serves as a template for a new DNA molecule, which consists of either both parental strands of DNA or both newly synthesized strands of DNA. A) True B) False Answer: B 68) DNA helicase is involved in "rewinding" the strands of DNA back into a helix after replication. A) True B) False Answer: B 69) DNA polymerase has the ability to match the nucleotide base in the parental strand with a free nucleotide that is complementary to that base. It then forms the covalent bonds between the nucleotides in the growing daughter strand of DNA. A) True B) False Answer: A 70) DNA replication occurs without errors due to the complementary base pairing used in the copying process. A) True B) False Answer: B 71) Most mutations are harmful or neutral, although in rare instances some can be beneficial. A) True B) False Answer: A

72) Inversions are movements of DNA from one chromosome to another. A) True B) False Answer: B SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 73) The molecule

carries the genetic "blueprints" for all forms of life on Earth.

Answer: DNA 74) By the early 1900s, scientists had determined that heritable information existed as discrete units called genes, which were located on . Answer: chromosomes 75) Chromosomes contain both and , and early-20th-century scientists were unsure which of these molecules carried the heritable units called genes. Answer: DNA; protein 76) The basic subunits of DNA are the

Answer: nucleotides 77) The DNA of chromosomes is composed of two strands wound about each other in the shape of a

Answer: double helix (or twisted ladder) 78) The X-ray diffraction studies of the scientists named the structure of the DNA molecule.

and

were essential for the discovery of

Answer: Wilkins; Franklin 79) At one end of a double helix, one strand has a free sugar (3') group and the other strand has a free group. Answer: phosphate 80) DNA

breaks the hydrogen bonds between complementary base pairs during DNA replication.

Answer: helicase 81) Segments of DNA that are made during replication are joined together by

Answer: DNAligase 82)

is the process whereby a molecule of DNA copies itself. Answer: DNAreplication

83) DNA is copied within eukaryotic cells in the process of

to produce two identical DNA molecules.

Answer: replication 84) DNA replication uses

base pairing to ensure genetic constancy.

Answer: complementary 85) DNA polymerase and other repair enzymes replication process.

the newly synthesized DNA strand during and after the

Answer: proofread (or correct) 12

86) Briefly describe the experiments conducted by Avery, McCarty, and MacLeod. What was the relevance of their research? Answer: The Avery, McCarty, and MacLeod experiments determined that the transforming agent in Griffith's experiments was DNA. Their experiments led to the connection between genes and DNA. 87) If cytosine makes up 15% of the bases in a sample of DNA from an organism, then adenine makes up what percentage of the bases? Answer: 35% 88) What are the three main components of a DNA nucleotide? Answer: A DNA nucleotide contains a sugar (deoxyribose), a phosphate group, and a nitrogen-containing base. 89) Name the four types of nitrogen-containing bases in DNA. Which bases are complementary? Answer: Adenine is complementary to thymine, and guanine is complementary to cytosine. 90) How are the four types of nitrogen-containing bases in DNA held together in the double helix of DNA? Answer: The bases are held together via hydrogen bonds. 91) When Hershey and Chase labeled phage with radioactive phosphorus, they concluded that the phage injects its DNA, not protein, into its host. These conclusions were based on the observation that the radioactive DNA ended up where? Answer: The DNA ended up inside the bacterium. 92) Briefly describe the basic process of DNA replication. Answer: DNA helicase unwinds the double helix of the parental DNA molecule. Then DNA polymerase pairs free nucleotides to be complementary to the parental DNA strand. The new nucleotides are then joined together to form two new strands of DNA paired with each of the original parental strands. 93) How do scientists know that proofreading occurs during and after the DNA replication process? Answer: DNA polymerase mismatches bases about once in every 10,000 to 1 million base pairs, but the actual mutation rate is one mistake in every 100 million to 10 billion base pairs. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

94) Based on this figure, which type(s) of bacteria would you expect to be isolated from the dead mouse in the final experiment (involving the mixture of bacterial strains)?

A) Living R-strain and heat-killed S-strainonly B) Heat-killed S-strain only C) Living R-strain only D) At least some living S-strain Answer: D

95) Based on this figure, which molecule would attach to the 5' phosphate end of the DNA strand on the right?

A) Adenine B) Phospholipid C) Phosphate D) Deoxyribose E) Cytosine Answer: D

96) Suppose a scientist working on a new drug for cancer developed a chemical that irreversibly breaks the hydrogen bonds in the DNA molecules within cancerous cells but leaves all of the covalent bonds intact. Hydrogen bonds are relatively weak compared to covalent bonds, and they are routinely broken and reformed as the DNA molecule is replicated in a normal cell. Their stability is nonetheless critical for maintaining certain aspects of the structure and function of the DNA molecule. Based on this scenario and your knowledge of DNA, how would this newly discovered chemical affect the "molecule of heredity" in a human cancer cell? A) It would result in constant DNA replication within the cell. B) It would allow the DNA molecule to function normally except during replication. C) It would break the individual strands of the DNA molecule apart, preventing it from functioning normally. D) It would break the two strands of the DNA molecule apart, preventing it from functioning normally. Answer: D 97) Bacterial cells have only one DNA molecule, which is double stranded and is replicated in essentially the same fashion as in eukaryotes. Imagine that, following the techniques of other scientists studying DNA, you created a bacterial cell that contains only radioactive nitrogen in its DNA. You then place the cell in a culture medium containing only "regular" (nonradioactive) nitrogen. Based on this scenario and your knowledge of DNA structure and replication, how many cells will contain some DNA with radioactive nitrogen after four rounds of cell replication? A) 2 B) 16 C) 8 D) 4 E) 1 Answer: A

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) The sequence of nitrogen-containing bases on one strand of DNA most directly determines the sequence of A) fatty acids in a fatmolecule. B) sugars in a polysaccharide molecule. C) bases in a protein molecule. D) amino acids in a protein molecule. Answer: D 2) The sequence of nitrogen-containing bases on one strand of DNA could determine all of the following EXCEPT the sequence of A) amino acids in a proteinmolecule. B) nitrogen-containing bases in mRNA. C) nitrogen-containing bases in the other DNA strand. D) ribose and phosphate molecules in tRNA. Answer: D 3) The "one-gene, one-enzyme" hypothesis concluded that A) DNA is transcribed into RNA, which is translated into protein. B) only certain genes function incells. C) each allele codes for a single type of protein. D) specific enzymes give rise to specific genes. E) enzymes regulate gene activity. Answer: C 4) Which of the following is noted when comparing DNA and RNA? A) No sugar is present in either molecule. B) Adenine pairs with different bases in DNA and RNA. C) Hydrogen bonding is important only in DNA. D) Only DNA has a backbone made up of sugars and phosphates. E) Thymine pairs with different bases in DNA and RNA. Answer: B 5) Which of the following is found in RNA but NOT in DNA? A) Phosphate groups B) Adenine C) Uracil D) Deoxyribose E) Thymine Answer: C 6) Both DNA and RNA A) are single-stranded molecules. B) contain the same four types of nitrogen-containing bases. C) contain phosphate groups. D) have the same five-carbon sugars. E) cannot be present in a cell simultaneously. Answer: C

7) How many consecutive mRNA bases are needed to specify an amino acid? A) 64 B) 3 C) 20 D) 4 Answer: B 8) What is the total number of different possible combinations of bases in a codon? A) 3 B) 20 C) 4 D) 64 Answer: D 9) If a bacterial protein is made from 30 amino acids, how many nucleotides are needed to code for its production? A) 600 B) 30 C) 90 D) 120 E) 60 Answer: C 10) The genetic material of some viruses, such as HIV, is not DNA but is instead A) lipid. B) RNA. C) carbohydrate. D) protein. Answer: B 11) Which of the following molecules function to transfer genetic information from one generation to the next? A) Lipid molecules B) mRNA C) tRNA D) DNA E) Proteinmolecules Answer: D 12) If the sequence of bases in a section of DNA is TAGGCTAA, what is the corresponding sequence of bases in mRNA? A) AATCGGAT B) CGAAUCGG C) TAGGCTAA D) ATCCGATT E) AUCCGAUU Answer: E

13) How many bases are in a codon? A) 4 B) 3 C) 20 D) 64 Answer: B 14) Which of the following has the fewest nucleotides in its strand? A) mRNA, having 75 nucleotides B) Protein, having 40 amino acids C) mRNA, having 100 bases D) Protein, with 2 polypeptides, each having 35 amino acids E) mRNA, having 50 codons Answer: A 15) The genetic code is A) read in sets of three bases called codons. B) used during the translation of DNA to mRNA. C) different in different organisms. D) a set of two base sequences coding for each amino acid. Answer: A 16) The process of copying genetic information from DNA to RNA is called A) replication. B) transformation. C) transcription. D) translation. Answer: C 17) Which of the following molecules transfers information from the nucleus to the cytoplasm? A) mRNA B) tRNA C) DNA D) Proteins E) Lipids Answer: A 18) The nitrogenous base uracil pairs with A) guanine. B) adenine. C) thymine. D) cytosine. E) uracil. Answer: B 19) How can RNA be distinguished from DNA? A) RNA lacks the baseuracil. B) RNA does not contain asugar. C) RNA is never found in the nucleus. D) RNA is single-stranded. Answer: D 3

20) If a tRNA molecule that is specialized for the transfer of the amino acid valine has the anticodon CAG, it will couple with the codon A) GAC. B) GUC. C) CAG. D) GTC. E) TUG. Answer: B 21) What is an anticodon? A) The beginning of a DNAmolecule B) Three consecutive bases in tRNA C) Three consecutive amino acids in a protein D) Four consecutive bases in tRNA E) Three consecutive bases in mRNA Answer: B 22) Transfer RNA A) brings amino acids to theribosome. B) is a nucleic acid that carries the code for the primary structure of a protein. C) transfers proteins into the nucleus. D) is a subunit ofribosomes. Answer: A 23) The type of RNA that binds to a specific amino acid is A) transfer RNA. B) messenger RNA. C) nuclear RNA. D) ribosomal RNA. Answer: A 24) What is the anticodon for AUC? A) UAG B) TAG C) GAU D) CUA E) AUC Answer: A 25) Ribosomes are a collection of A) proteins and small RNAs that function in translation. B) proteins and mRNAs that function in translation. C) mRNAs and tRNAs that function in translation. D) small proteins that function intranslation. E) proteins and tRNAs that function in transcription. Answer: A

26) Which of the following contains four types of nucleotides but no uracil? A) Ribosomal RNA B) DNA C) Messenger RNA D) Transfer RNA E) RNA polymerase Answer: B 27) Which of the following has two polynucleotide strands? A) Ribosomal RNA B) DNA C) Messenger RNA D) Transfer RNA E) RNA polymerase Answer: B 28) Which of the following contains deoxyribose? A) Ribosomal RNA B) DNA C) Messenger RNA D) Transfer RNA E) RNA polymerase Answer: B 29) The function of the promoter is to signal the RNA polymerase A) where to start transcribing the DNA. B) where to add the first amino acid to the protein. C) where to start translating the DNA. D) which strand of the DNA to read. Answer: A 30) Transcription is the process of A) assembling an RNA molecule without a template. B) synthesizing a DNA molecule from an RNA template. C) replicating a single-stranded DNA molecule. D) synthesizing a protein using information from mRNA. E) synthesizing an RNA molecule using a DNA template. Answer: E 31) A transcription start signal is called a(n) A) origin. B) initiation codon. C) nonsense codon. D) promoter. E) start site. Answer: D

32) What does mRNA carry away from the nucleus? A) Information B) Ribosomes C) tRNA D) Amino acids E) Enzymes Answer: A 33) Suppose one strand of a "mini-gene" has the base sequence TACCCGGATTCA. The last codon in the mRNA sequence will be A) AGT. B) UGA. C) TCA. D) AGU. Answer: D 34) Which statement correctly describes transcription? A) RNA chains of all genes are synthesized from the same DNA strand, with the growing RNA strand always starting at the 3' end and moving toward the 5' end. B) RNA chains of all genes are synthesized from the same DNA strand, with the growing RNA strand always starting at the 5' end and moving toward the 3' end. C) RNA chains of different genes can be transcribed from either DNA strand, with RNA polymerase traveling from the 5' end and moving toward the 3' end. D) RNA chains of different genes can be transcribed from either DNA strand, with RNA polymerase traveling from the 3' end and moving toward the 5' end. Answer: D 35) In eukaryotes, a promoter that signals the beginning of the gene and binds with the promoter typically consists of A) the bases TATAAA and response elements. B) both DNA and RNA. C) rRNA and tRNA. D) the base sequence AUG and transcription factor binding sites. Answer: A 36) Which of the following occurs in the nucleus? A) Transcription only B) Both translation and replication of genetic material C) Both transcription and replication of genetic material D) Translation only E) Replication of genetic material only Answer: C 37) The process of converting the "message" of mRNA into a sequence of amino acids is called A) repression. B) replication. C) translation. D) activation. E) transcription. Answer: C

38) What is the site of protein synthesis in the cell? A) Eukaryotic chromosome B) Nucleolus C) Smooth endoplasmic reticulum D) Nucleus E) Ribosome Answer: E 39) All of the following are directly involved in translation EXCEPT A) tRNA. B) DNA. C) amino acids. D) ribosomes. E) mRNA. Answer: B 40) Suppose one strand of a "mini-gene" has the base sequence TACCCGGATTCA. If we assume no introns are involved, how many amino acids does the polypeptide encoded by this gene have? A) 6 B) 4 C) 2 D) 12 Answer: B 41) The manufacture of proteins from RNA and amino acids is referred to as A) replication. B) activation. C) translation. D) transformation. E) transcription. Answer: C 42) Suppose the template DNA strand of a "mini-gene" has the base sequence TACCCGGATTCA. The anticodon of the tRNA that carries the first amino acid to the ribosome will be A) AGU. B) UCA. C) UAG. D) UAC. E) AUG. Answer: C 43) A sequence of three RNA bases can function as a(n) A) codon only. B) gene only. C) codon or anticodon. D) anticodon only. Answer: C

44) In a wild-type strain of fruit flies, the length of a gene from the start to the stop codon is 2,000 DNA bases. Suppose an experiment indicated that the mRNA molecule transcribed from this gene is much shorter (only 1,200 bases). What is the most likely explanation for this? A) A mutation caused the formation of an extra stop codon in the gene. B) The mRNA was prematurely degraded. C) The first 800 bases of DNA are always cut out as it is transcribed into mRNA. D) There are introns in the DNA that were cut out of the mRNA. Answer: D 45) What molecule is responsible for translation of the four-letter "nucleic acid language" (A, T, G, and C nucleotides) into the 20 "amino acid language" of proteins by bringing in amino acids to the ribosome? A) Messenger RNA B) DNA C) Transfer RNA D) Ribosomal RNA Answer: C 46) A tRNA that carries a specific amino acid enters the protein-synthesizing machinery at the ribosomes and pairs with the appropriate A) anticodon. B) codon. C) amino acid. D) charge. Answer: B 47) A tRNA molecule brings A) a polypeptide B) mRNA C) RNA polymerase D) an amino acid

to the ribosome during proteinsynthesis.

Answer: D 48) Which of the following attaches to specific amino acids? A) Ribosomal RNA B) Messenger RNA C) RNA polymerase D) Transfer RNA E) DNA Answer: D 49) Which of the following has anticodons? A) RNA polymerase B) Ribosomal RNA C) Transfer RNA D) Messenger RNA E) DNA Answer: C

50) Which of the following is a protein made up of amino acids? A) DNA B) Messenger RNA C) Uracil D) RNA polymerase E) Transfer RNA Answer: D 51) Which of the following binds to codons? A) RNA polymerase B) Messenger RNA C) DNA D) Transfer RNA Answer: D 52) Which of the following contains codons? A) Messenger RNA B) RNA polymerase C) Ribosomal RNA D) Transfer RNA E) DNA Answer: A 53) Which of the following synthesizes RNA molecules in the nucleus? A) Messenger RNA B) Ribosomal RNA C) Transfer RNA D) RNA polymerase E) DNA Answer: D 54) A random change in a DNA nucleotide base sequence A) is never apparent in the organism. B) is never beneficial to the organism. C) cannot have an influence on genetic variation. D) represents a mutation. E) always kills the cell. Answer: D 55) A gene mutation is defined as changein the A) activation of a gene. B) structure of ribosomes. C) nucleotide sequence of DNA. D) nucleotide sequence of RNA. Answer: C

56) For a mutation to affect the evolution of an animal species, it must occur within A) diploid cells. B) prokaryotic cells. C) gametes. D) somatic cells. Answer: C 57) A mutation that results in a change in the codon-reading pattern could result from A) a base deletion only. B) a base insertion only. C) a base substitution only. D) either an insertion or a deletion of a base. Answer: D 58) Which point mutation would be most likely to have a catastrophic effect? A) The deletion of three bases near the start of the coding sequence B) A base insertion near the end of the coding sequence C) A base deletion near the end of the coding sequence D) A base deletion near the start of the coding sequence E) A basesubstitution Answer: D 59) What kind of mutation occurs when one base is changed to another at a single location in the DNA? A) Deletion B) Insertion C) Neutral D) Substitution Answer: D 60) A gene can be mutated with no resulting functional change in the protein that is produced from that gene if A) an entire codon has been removed. B) RNA polymerase can edit the mutation from the mRNA produced during translation. C) the mutation alters the active site of an enzyme. D) a codon has changed, but it codes for the same amino acid as the original codon. Answer: D 61) A "mini-gene" has the base sequence TACCCGTGCACG. If the T at the beginning of the sequence is deleted, what will be the consequence? A) RNA polymerase will correct the deletion, and a normal protein will be produced. B) Only the amino acid coded for in that codon will be changed. C) All of the codons after that point will be changed. D) RNA polymerase will skip that codon, but all the others will be read normally. E) The first nucleotide is always replaced anyway, so there will be no change. Answer: C

62) A "mini-gene" has the base sequence TACCCGTGCACG. Which of the following sequences represents a single base substitution? A) TACCCGAGCACG B) TACCCGGCACG C) TACCGTGCTACG D) TACCCGTGTCACG E) TACCCGTGCACG Answer: A 63) Gene expression is a term that relates to A) DNA replication. B) the unique set of genes in an individual. C) the karyotype of a chromosomeset. D) how genes are passed from parent to offspring. E) the flow of genetic information from DNA to proteins. Answer: E 64) Which of the following is TRUE regarding gene expression? A) Gene expression is not influenced by the environment. B) Different individuals of the same species express all of the same genes. C) Different tissues within an organism express different genes. D) Gene expression remains constant throughout an organism's life span. Answer: C 65) Which of the following is NOT a means of regulating gene expression? A) Modifying proteins after they aresynthesized B) Regulating how long a protein lasts in a cell C) Deleting genes from cells in which they are not needed D) Varying the rate at which messenger RNAs are translated E) Varying the rate at which messenger RNAs are transcribed Answer: C 66) The fact that calico cats are only female supports the theory of A) X-chromosome inactivation and Barr bodies in females. B) testosterone inactivation of Y-chromosome genes. C) mutations in all genes on one X chromosome. D) two X chromosomes being required for coat color in cats. Answer: A 67) How can a single gene code for more than one protein? A) Different RNA polymerases transcribe it and produce different proteins. B) Different amino acid chains can be coded by the same mRNA. C) The exons within an mRNA can be spliced together in different ways. D) Different types of ribosomes translate the resulting mRNA, producing different proteins. Answer: C

68) Your tongue does NOT grow hair because A) the genes for hair proteins have been deleted from the cells of your tongue. B) different genes are expressed in different tissues. C) saliva prevents hair from growing. D) skin cells have extra DNA that codes for hair proteins. Answer: B 69) Which of the following is NOT a theory of epigenetics explaining how cells can change gene function without changing the DNA basesequence? A) Modification of DNA B) Modification of chromosomal proteins C) Altering transcription and translation with noncoding RNA D) Mutations causing new beneficial alleles Answer: D 70) What is an advantage to an organism producing microRNA? A) microRNA can protect against heart disease and cancer. B) microRNA allows for the inactivation of Barr bodies. C) microRNA can protectagainst viral infections. D) microRNA causes mutations in unused genes. Answer: C 71) Messenger RNA is single-stranded. A) True B) False Answer: A 72) In general, each gene codes for a specific protein. A) True B) False Answer: A 73) A codon of mRNA consists of three bases that code for an amino acid. A) True B) False Answer: A 74) The site of protein synthesis in the cytoplasm is the ribosome. A) True B) False Answer: A 75) Each ribosome is specific for a particular type of protein. A) True B) False Answer: B

76) tRNA is necessary for transcription to occur. A) True B) False Answer: B 77) Steroid hormones have the ability to regulate transcription. A) True B) False Answer: A 78) The Barr body is the X chromosome in the cell that is expressed, whereas the other X chromosome is inactivated. A) True B) False Answer: B SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 79) The strand of the DNA molecule that is transcribed is called the

strand.

Answer: template 80) In eukaryotic cells, the ribosome for

occurs in the nucleus, resulting in the production of mRNA, which then travels to into an amino acid chain.

Answer: transcription; translation 81) The anticodon for the codon AUC is

Answer: UAG 82) A random change in the DNA nucleotide base sequence is called a

Answer: mutation 83) A mutation in which one nucleotide in the DNA sequence is substituted for another nucleotide is referred to as a mutation. Answer: point 84) In females, an entire X chromosome is inactivated in each cell. The inactivated X chromosome is called the . Answer: Barr body 85) In the intestinal bacteria Escherichia coli, the DNA segment that contains the coding for the enzymes of lactose metabolism is called the lactose . Answer: operon 86) List three ways in which an RNA molecule differs from a DNA molecule. Answer: RNA is normally single-stranded, whereas DNA is double-stranded. RNA has the sugar ribose, whereas DNA has deoxyribose. RNA uses the base uracil, whereas DNA uses thymine. 87) Determine the sequence of bases in mRNA if the original DNA base sequence is TAGGCTAA. Answer: AUCCGAUU

88) Describe the three basic steps or processes involved in transcription. Answer: First, initiation involves RNA polymerase binding to a specific promoter region on the template strand of the DNA molecule. Second, elongation involves RNA polymerase moving along the DNA template strand and adding the appropriate complementary RNA nucleotides. Third, termination occurs when the RNA polymerase reaches a termination signal on the DNA template strand, and the new mRNA is released to move onto the cytoplasm. 89) Compare and contrast the three major RNA molecules involved in translation. Answer: mRNA, tRNA, and rRNA are all single-stranded RNA molecules transcribed from DNA that play distinct roles in the translation process. mRNA carries information from the DNA molecule for the sequence of amino acids for the polypeptide. tRNA carries the amino acids that correspond to specific codon units (on the mRNA via its anticodon). rRNA molecules are important subunits of the ribosome, which is the site of translation. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 90) Based on this table, which polypeptide would be synthesized from the mRNA base sequence AUGCCUGACUUA?

A) met-pro-asp-leu B) met-pro-asp-tyr C) ile-pro-ala-tyr D) phe-met-pro-leu E) met-phe-glu-leu Answer: A

91) As seen in this figure, how many exons were used to assemble the pre-mRNA sequence, and how many exons were used in the finished mRNA?

A) 5; 3 B) 3; 3 C) 3; 2 D) 6; 3 Answer: B 92) In the fungus Neurospora, a metabolic pathway synthesizes the amino acid Z (which is essential for its survival) from the precursor W. The intermediates X and Y are also produced in this pathway. The enzymes E1, E2, and E3 catalyze three reactions in the process, as follows: E1 E2 E3 W→X→Y→Z X- ray radiation can be used to create a mutant strain of Neurospora that has a defective gene sequence for E2. Based on this scenario, the mutant strain will survive on media that contain A) only Y or Z. B) W, X, Y, or Z. C) only W or X. D) only X. E) only Z. Answer: A

93) Imagine that the short DNA base sequence GGCTGC is transcribed and then translated by a ribosome. The following activated tRNA molecules are available in the cytoplasm: tRNA Anticodon Amino Acid GGC proline CGU alanine UGC threonine CCG glycine ACG cysteine CGG alanine What resulting dipeptide will form? A) Proline-threonine B) Alanine-alanine C) Threonine-glycine D) Cysteine-alanine E) Glycine-cysteine Answer: A

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) All of the following are goals of biotechnology EXCEPT A) treating disease more effectively. B) generating economic benefits. C) improving agriculturally important food plants. D) efficiently producing biologically important molecules. E) creating humans with higher intelligence levels. Answer: E 2) What is the term for manipulating the molecular basis of inheritance via recombinant DNA technology? A) DNA fingerprinting B) Restriction fragment length polymorphism (RFLP) C) Biotechnology D) Mendelian genetics E) Polymerase chain reaction (PCR) Answer: C 3) Which of the following is NOT a use for biotechnology? A) Producing effective and safe vaccines B) Identifying human fetuses with particular genetic diseases C) Producing large quantities of particular human proteins D) Altering food plants to increase yields E) Altering the intelligence levels of newborn infants Answer: E 4) The history of biotechnology spans A) at least 10,000 years. B) around 100 to 150 years. C) about 1,000 years. D) fewer than 50 years. Answer: A 5) Which of the following results from inserting foreign DNA into an organism to produce a new gene combination? A) Translation B) Recombinant DNA C) Mutations D) Regulatory genes E) Gene cloning Answer: B 6) An organism that contains foreign DNA, which was inserted into its own genetic material, is called A) electrophoresed. B) foreign. C) transgenic. D) polygenic. Answer: C

7) An organism that contains altered genes is considered all of the following EXCEPT A) a genetically modified organism (GMO). B) genetically engineered. C) transgenic. D) polymorphic. Answer: D 8) The earliest examples of biotechnology included the A) use of genetic markers to learn more about genetic inheritance. B) study and treatment of genetic diseases in people. C) use of selective breeding to provide better, more nutritious food. D) careful examination of patterns of bacterial inheritance. Answer: C 9) Small, accessory chromosomes found in bacteria that are useful in recombinant DNA procedures are called A) bacteriophages. B) centrioles. C) viroids. D) plasmids. Answer: D 10) The geneticrecombination of caused massive, widespread epidemics that affected the global human population several times in the twentieth century. A) human and bacterial plasmids B) HIV and flu viruses C) bird flu viruses and human flu viruses D) bacterial and viral plasmids Answer: C 11) Plasmids are A) necessary for bacteria to reproduce. B) small, replicating rings of DNA found in bacteria. C) noncircular DNA segments found only in bacteria. D) chromosomal loops made of RNA. E) found only in three species of bacteria. Answer: B 12) Which of the following is NOT an example of genetic recombination between different species in nature? A) Viruses that transfer DNA between host organisms B) Bacteria that acquire foreign plasmids C) Sexual reproduction D) Bacterial transformation Answer: C 13) Recombinant DNA technology A) involves combining existing genes from different organisms. B) will never be of economicimportance. C) randomly creates new genes from free nucleotides. D) is always dangerous and inevitably leads to mutations and mistakes. E) involves only changing genes in large mammals. Answer: A 2

14) DNA from different bacteria may be combined using all of the following EXCEPT A) cloning. B) viruses. C) plasmids. D) transformation. Answer: A 15) Which of the following is NOT a natural means of DNA recombination? A) Sexual reproduction B) Viral infection C) Transformation in bacteria D) PCR Answer: D 16) In biotechnology research, DNA fragments created by restriction enzyme action are separated from one another via A) centrifugation. B) gel electrophoresis. C) PCR. D) filtering. E) crossing over. Answer: B 17) PCR is essential for A) analyzing a person's fingerprints. B) creating recombinant plasmids. C) allowing restriction enzymes to cut DNA. D) cutting DNA into many smallpieces. E) making many copies of a small amount of DNA. Answer: E 18) How many copies of a particular gene of interest are produced from a single template DNA strand after three cycles of PCR? A) Five B) Eight C) Four D) Two E) Three Answer: B 19) Which of the following is the correct sequence of PCR? A) Heat to 90°C (to bind primers and enzymes), then cool to 50°C (to separate DNA), and then reheat to 70°C (to synthesize DNA). B) Heat to 90°C (to separate DNA), then cool to 50°C (to bind primers and enzymes), and then reheat to 70°C (to synthesize DNA). C) Heat to 70°C (to bind primers and enzymes), then cool to 50°C (to synthesize DNA), and then reheat to 90°C (to separate DNA). D) Heat to 70°C (to separate DNA), then cool to 50°C (to bind primers and enzymes), and then reheat to 90°C (to synthesize DNA). Answer: B

20) DNA moves within an electric field because it A) is negatively charged. B) can possess different charges (positive or negative), depending on its base sequence. C) is positively charged. D) makes up chromosomes, which are slightly electromagnetic. Answer: A 21) PCR enables scientists to do all of the following EXCEPT A) sequence the bases within a gene as it is being copied. B) make billions of copies of a particular gene. C) make gene copies quite cheaply. D) use a very small amount of DNA as starting material. E) make gene copies very rapidly. Answer: A 22) Modern forensic biotechnology labs use sophisticated machines to analyze determine the number of specific genetic repeats in the samples. A) AIDs B) primers C) (STRs) D) PCRs

, such as D16, and to

Answer: C 23) Which of the following is currently used by the U.S. Department of Justice as a form of genetic "fingerprints" of criminals? A) PCRs B) The genes responsible for producing the unique patterns of swirls and loops on a person's fingers C) The number of introns in a chromosome D) Plasmids E) STRs Answer: E 24) Specific fragments of DNA on a gel can be visualized using A) STRs. B) PCR. C) electrophoresis. D) restriction enzymes. E) DNA probes. Answer: E 25) If the DNA fingerprint of a suspect does NOT match a blood sample from a crime scene, what can you conclude? A) The DNA in the blood sample probably degraded in a short period of time. B) The suspect was never at the crime scene. C) The suspect may have been at the crime scene, because DNA fingerprinting has a large error rate. D) The blood sample had to come from another person, but the suspect may still have been there. Answer: D

26) DNA is negatively charged because of its A) ribose molecules. B) bases. C) phosphate groups. D) large molecular size. E) deoxyribose molecules. Answer: C 27) Which of the following techniques amplifies a specific region of DNA? A) Gel electrophoresis B) The use of DNA probes C) PCR D) DNA profiles Answer: C 28) How does DNA move during gel electrophoresis? A) Larger pieces of DNA move at a faster rate. B) The DNA moves toward the negative electrode. C) Smaller pieces of DNA move faster toward the positive electrode. D) DNA moves at a constant rate, regardless of fragment size. Answer: C 29) Which of the following molecular techniques involves "DNA replication in a tube"? A) PCR B) STR C) Gel electrophoresis D) Transformation Answer: A 30) The enzymes used to cut genes in recombinant DNA research are called A) spliceosomes. B) DNA polymerases. C) restriction enzymes. D) RNA polymerases. E) replicases. Answer: C 31) In recombinant DNA technology, plasmids A) are used to insert foreign DNA into bacteria. B) are the sites of protein synthesis in bacteria. C) are necessary for cellular respiration in certain plants. D) show restriction enzymes where to cut bacterial DNA. E) are isolated from the blood of mammals. Answer: A 32) The term transfecting refers to A) making GMOs that are sterile. B) making multiple copies of a small sample of DNA. C) inserting the gene of interest into the host organism. D) viral DNA becoming part of human DNA. Answer: C 5

33) Which pair of enzymes is necessary to make recombinant DNA? A) DNA polymerase and DNA ligase B) DNA polymerase and RNA polymerase C) Restriction enzyme and DNA polymerase D) Restriction enzyme and DNA ligase Answer: D 34) To join a fragment of human DNA to bacterial or yeast DNA, both the human DNA and the bacterial or yeast DNA must first be treated with the same A) restriction enzyme. B) DNA gyrase. C) DNA polymerase. D) DNA ligase. Answer: A 35) Restriction enzymes are useful in recombinant DNA studies because they A) can separate pieces of DNA and RNA from each other. B) cut DNA only at specificlocations. C) join the cut ends of small DNA molecules. D) give plasmids antibiotic properties. E) can reproduce in bacteria. Answer: B 36) Restriction enzymes A) randomly cut DNA into smallpieces. B) can cut only bacterial DNA. C) separate the strands of DNA during PCR. D) produce single-stranded DNA fragments with "sticky ends." Answer: D 37) What is an advantage to a farmer using an insect-resistant crop plant? A) Sterile plants, with inability to form strange hybrids B) More herbicide use but less pesticide use C) Less pesticide use and better crop yields D) More pesticide use and better crop yields Answer: C 38) Suppose ENZ-1 and ENZ-2 are two different restriction enzymes. If various pieces of DNA from different species are cut with these enzymes (as follows), which would most easily form recombinant molecules? A) Human DNA cut with ENZ-2 and gorilla cut with ENZ-2 B) Bacterial DNA cut with ENZ-1 and bacterial DNA cut with ENZ-2 C) Human DNA cut with ENZ-1 and human DNA cut with ENZ-2 D) Human DNA cut with ENZ-1 and gorilla DNA cut with ENZ-2 Answer: A

39) If you cut out a gene using the restriction enzymes EcoRI and BamHI, what enzyme(s) will you need to insert the gene into another chromosome? A) EcoRI only B) BamHI only C) Both EcoRI and BamHI D) Neither of these enzymes Answer: C 40) In 2011, more than 85% of the A) corn and soybeans (only) B) cotton (only) C) corn, cotton, and soybeans D) soybeans (only) E) corn (only)

grown in the United States was transgenic.

Answer: C 41) Which of the following applications of biotechnology results in an insect-resistant plant? A) Growth-hormone-treated cows B) Banana-based vaccine against pathogenic Escherichia coli C) Insulin production by bacteria D) Herbicide-resistant corn E) Bt toxin production by soybeans Answer: E 42) All of the following are benefits of sequencing the human genome EXCEPT A) better comparisons can be made between human genetics and the genetics of other organisms. B) every genetic disorder is now curable or preventable. C) more genes that cause disease have been discovered. D) the number of genetic disorders that can be diagnosed with molecular techniques has increased. E) genes were discovered whose functions were previously unknown. Answer: B 43) The human genome contains about A) 100 B) 1 billion C) 20,000 to 25,000 D) 1,800 E) 1 million

genes.

Answer: C 44) Sequencing the genes of humans is important because A) knowing the nucleotide sequence of human genes will aid in the treatment of diseases caused by them. B) it will allow scientists to create human clones. C) it will give us a better understanding of agricultural animals. D) it provides information on how to build lipids in the cell. Answer: A

45) All of the following have been produced by inserting human genes into bacteria EXCEPT A) clot-dissolving enzymes, which help heart attack victims recover. B) growth hormone, which helps children grow normally. C) blood-clotting enzymes, which treat hemophiliacs. D) cancer-cell-killing hormones, which cure patients who have malignancies. E) insulin, which treats diabetics. Answer: D 46) Which of the following can be used to detect genetic disorders? A) Restriction enzyme fragments only B) STRs only C) Restriction enzyme fragments and DNA probe arrays only D) Arrays of DNA probes only Answer: C 47) If you want to develop a procedure for identifying a genetic disorder caused by 20 different alleles, what method is most likely to be useful? A) STRs B) Arrays of DNA probes on filter paper C) PCR D) Gene therapy Answer: B 48) Which of the following involves the use of human genes? A) Banana-based vaccine against pathogenic E. coli B) Genetically altered soybean oils C) Herbicide-resistant corn D) Insulin production by bacteria E) Bt toxin production by soybeans Answer: D 49) Which of the following was successfully used to treat a patient with severe combined immunodeficiency (SCID)? A) Gene therapy B) Bt toxins C) Insulin D) Growth hormones E) Vaccines Answer: A 50) Controversy has arisen about using genetically engineered bovine growth hormone to increase milk yield in cattle. The lesson gained from this controversy is that A) humans are not wise enough to use this technique properly. B) recombinant DNA technology is inherently a bad idea and should be abandoned. C) the whole human society should decide the proper uses of recombinant DNA technology. D) society should let scientists decide the proper uses of recombinant DNA technology. E) citizens should not be allowed to decide such issues, as they tend to make decisions based on emotion. Answer: C

51) Which of the following is NOT a valid difference between traditional and modern forms of biotechnology? A) Traditional biotechnology was based solely on selective breeding. B) Traditional biotechnology can produce cloned animals with new genes. C) Modern biotechnology can isolate and manipulate individual genes. D) Modern forms of biotechnology are slower than traditional forms of biotechnology. Answer: D 52) Which of the following is a valid difference between traditional (selective breeding) and modern (genetic engineering) forms of biotechnology? A) Genetic engineering can use genes from unrelated species, whereas selective breeding must use genes from the same or very closely related individuals. B) Genetic engineering can alter the DNA sequence of entire populations, whereas selective breeding cannot. C) Selective breeding can be done much more quickly than can genetic engineering. Answer: A 53) In the 1990s, researchers attempted to improve the balance of amino acids in soybean protein by inserting a gene from Brazil nuts. Which of the following is the best reason as to why the transgenic soybeans have never been grown commercially? A) The modified soybeans could not grow with the foreign gene present. B) Some people were allergic to the protein product of the Brazil nut gene. C) Regulatory hurdles made the modified soybeans too expensive to market profitably. D) The public was misinformed by food-safety advocates and refused to buy products made from the modified soybeans. Answer: B 54) Which of the following is a valid scientific concern about the environment and transgenic crops? A) Eating transgenic foods will permanently change human DNA. B) The toxic products of the modified genes would be released to the environment when the plants die, resulting in drastic die-offs of local wildlife. C) Pollen from transgenic crops could carry the recombinant genes to wild relatives, with unpredictable consequences. D) Wild animals might eat the transgenic crops and become genetically mutated. Answer: C 55) Prenatal diagnosis is available for all of the following disorders EXCEPT A) sickle-cell anemia. B) AIDS. C) Down syndrome. D) cystic fibrosis. Answer: B 56) Which of the following techniques is most commonly used in the prenatal diagnosis of genetic disorders, such as cystic fibrosis, in a human fetus? A) Isolation of fetal cells from maternal blood B) Amniocentesis C) Chorionic villus sampling Answer: B

57) All of the following are ways in which scientists can transfect an organism EXCEPT A) spraying plants with herbicide containing new genes. B) injecting DNA into an egg using a small, sharp pipette. C) using a "gene gun" to shoot genes into cells in culture. D) infecting a host organism with a virus carrying a new gene. Answer: D 58) In nature, DNA recombination occurs but it is random and undirected. A) True B) False Answer: A 59) DNA recombination changes the genetic makeup of organisms. A) True B) False Answer: A 60) Sexual reproduction in humans is an example of DNA recombination. A) True B) False Answer: A 61) A recombinant plasmid contains only human and bacterial DNA. A) True B) False Answer: B 62) PCR joins many small DNA molecules into a long chain. A) True B) False Answer: B 63) Individuals within the same species have the same DNA "fingerprint," but individuals from different species have different DNA fingerprints. A) True B) False Answer: B 64) The discovery of the organism Thermus aquaticus was critical for the development of the technique of PCR. A) True B) False Answer: A 65) Restriction enzymes are "restricted" in the sense that they normally work on only bacterial DNA. A) True B) False Answer: B

66) Ligase enzymes are used to covalently bind together pieces of DNA. A) True B) False Answer: A 67) Restriction enzymes have the ability to cut DNA at specific nucleotide sequences. A) True B) False Answer: A 68) The DNA of humans and chimps differs by about 10%. A) True B) False Answer: B 69) About 90% of the human genome contains the genes. A) True B) False Answer: B 70) There are potential risks in performing recombinant DNA research on humans and plants. A) True B) False Answer: A 71) Stringent safety rules are not necessary for recombinant DNA research because it is a natural process that occurs in the absence of humanintervention. A) True B) False Answer: B SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 72)

animals and plants contain DNA inserted in them from another species. Answer: Transgenic

73)

are small, circular pieces of DNA that are often used in the process of transformation. Answer: Plasmids

74) In gel electrophoresis, DNA is separated based on charge and

Answer: size 75) A radioactively labeled single-stranded DNA electrophoresis gel.

can be used to identify a specific piece of DNA in an

Answer: probe 76) Enzymes thatcutdouble-stranded DNAatspecific sitesarecalled Answer: restriction enzymes

77) An important tool of genetic engineering is from a different organism.

DNA, which is DNA altered by the incorporation of genes

Answer: recombinant 78) Golden Rice was originally developed to provide a source of food.

to people for whom rice is the principal

Answer: vitamin A 79) Define the term biotechnology. Answer: Biotechnology is any genetic alteration of organisms, cells, or biological molecules to achieve specific practical goals. 80) How were ancient peoples involved in biotechnology? Answer: Ancient peoples practiced the selective breeding of plants and animals, which is a form of biotechnology. 81) How is it possible for a dead bacterial cell to influence the DNA in a living bacterial cell? Answer: Dead bacteria release plasmids, which can be taken up by other bacteria through the process of transformation, passing along any genetic information that was on the plasmid to the live organism. 82) Describe one technique that can be used to generate multiple copies of a gene that is of interest to a researcher. Answer: The researcher can make copies of a gene within a bacterium (or other organism) or via PCR. 83) What is the advantage of using PCR over traditional bacterial cloning to generate large quantities of a specific piece of DNA? Answer: PCR is faster and cheaper than is traditional bacterial cloning. 84) Compare and contrast the use of a DNA profile ("DNA fingerprinting") with regular ink fingerprinting. Answer: Both have the ability to distinguish individuals and can be used in a court of law; however, DNA fingerprinting techniques can be used when only minuscule human samples are left at a crime scene (blood, semen, hair, etc.) and can also be used for paternity and rape cases. 85) Provide one example of an agricultural application of biotechnology. Answer: Possible answers are selective breeding, pest resistance, and increased marketability of crops (tomatoes). 86) Provide one example of a medical application of biotechnology. Answer: Possible answers are genetic screening, animal models of human diseases, therapeutic proteins (insulin and vaccines), and gene therapy. 87) Describe how the technique of gene therapy might help someone who has an inherited genetic disease as well as future children and grandchildren. Answer: Gene therapy might be able to replace defective genes in the cells and gametes of the individual who has the disease, so that the disease is not fully expressed in that individual or passed on to offspring. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

88) Based on this figure, how many PCR cycles are necessary to produce 64 copies of the original DNA fragment being amplified?

A) Four B) Six C) One D) Three E) Two Answer: B

89) The illustrated probe cannot bind to the shown DNA sequence. Which DNA sequence could this probe bind to?

A) AGAGATATCTAT B) AGATCTATCTAT C) AGATAGATAGAT D) AGAGATATGATA Answer: C 90) For years, the residents of a small Mexican town complained about the filth from a nearby hog farm, where millions of pigs are raised each year. In 2009, the majority of residents in this town became sick with "swine flu," caused by the H1N1 influenza virus. This virus infects people but is apparently genetically similar to a virus that infects hogs. The virus has since gone on to infect (and, in some cases, kill) people in Mexico City, and has quickly spread around the entire planet. The "swine flu" has been declared a global pandemic. Based on this scenario and your knowledge of genetics, what is a potential technique that could be used to prevent this disease? A) Make recombinant viral and human DNA. B) Encourage people not to consume pig products. C) Develop a technique for STRs in swine. D) Genetically engineer flu-resistant pigs. Answer: D 91) Imagine that it is 1965 and the bacterium Thermus aquaticus has not yet been discovered. As a geneticist interested in forensics applications, you are attempting to develop a gene-amplifying technique similar to PCR. In a test tube, you place a DNA sample, free nucleotides, human DNA polymerase, and the appropriate primers for the DNA sequence being analyzed. You first heat the sample to 90°C, then cool it to 50°C, and then reheat it to 70°C. Based on this scenario and your knowledge of how modern PCR works, the result of these procedures will be A) unsuccessful, because the enzyme will denature during the second step (cooling). B) successful copying of the DNA, because it follows modern PCR procedures almost perfectly. C) unsuccessful, because the enzyme will denature during the third step (reheating). D) unsuccessful, because human DNA polymerase cannot recognize the primers used. E) unsuccessful, because the enzyme will denature during the first step (heating). Answer: E

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Plato's view of species A) did not allow for evolutionary change. B) included species that do not actually exist. C) was similar to the modern concept of evolution. D) allowed for limited evolution withinspecies. E) recognized that each individual in a species is unique. Answer: A 2) Whose philosophy was based on the "ideal form"? A) Darwin and Wallace B) Lamarck C) Darwin D) Cuvier E) Plato Answer: E 3) Who proposed the geological theory of catastrophism? A) Cuvier B) Lamarck C) Plato D) Darwin and Wallace E) Darwin Answer: A 4) Which of these statements best illustrates the theory of catastrophism? A) Only extinct species appear in the fossil record. B) Species become extinct due to natural disasters, such as floods and volcanic eruptions. C) Only plant species have become extinct. D) There are no humans in early fossil records because they had not been created yet. E) The fossil record is incomplete. Answer: B 5) Which geologist described the age of the Earth as "eternal"? A) Lyell B) Buffon C) Aristotle D) Lamarck E) Malthus Answer: A 6) The concept that Earth's present landscape is due to gradual geological processes was proposed by A) Lyell. B) Buffon. C) Aristotle. D) Lamarck. E) Malthus. Answer: A

7) Which statement illustrates Lamarck's theory on the mechanism of evolution? A) Birds with bright colors will attract more mates and pass on the colorful plumage. B) Giraffes with longer necks survived and reproduced faster because they could reach a better food source. C) A man who routinely shaves the hair off his head will have sons who become bald. D) Fish with coloration that matches the river bottom they inhabit will survive to reproduce. E) Plants that can survive in less light will become the dominant species in shaded areas. Answer: C 8) The idea that physical changes I make to myself will be passed on to my children was proposed by A) Lyell. B) Darwin. C) Lamarck. D) Plato. E) Cuvier. Answer: C 9) Which scientist devised the theory of uniformitarianism to account for Earth's old age? A) Darwin B) Plato C) Cuvier D) Lyell E) Lamarck Answer: D 10) The publication date of On the Origin of Species by Means of Natural Selection is A) 1900. B) 1869. C) 1859. D) 1809. E) 1830. Answer: C 11) Who wrote On the Origin of Species by Means of Natural Selection? A) Wallace B) Mendel C) Darwin D) Malthus E) Lamarck Answer: C 12) Who presented the idea of natural selection to the Linnaean Society in 1858? A) Plato B) Lamarck C) Darwin and Wallace D) Cuvier E) Darwin Answer: C

13) Who suggested that giraffes developed their long necks over time by stretching? A) Plato B) Cuvier C) Wallace D) Lamarck E) Darwin Answer: D 14) Fossils include rocks and sedimentsthat A) have been shaped by people to resemble plants or animals. B) bear the impressions or shapes of preserved organisms. C) have been shaped by wind and water to resemble lifelike forms. D) all of the above. Answer: B 15) Modern geologists estimate that the age of Earth is about A) 4.5 billion years. B) 4,500 years. C) 4.5 trillion years. D) 4.5 million years. E) 450,000 years. Answer: A 16) Which of the following is NOT one of Darwin's postulates? A) In each generation, some individuals reproduce and others don't. B) Luck is an important factor in determining the fate of individuals. C) Through natural selection, individuals with useful traits survive longest and leave the most offspring D) There is variation among members of a population. E) Some of the differences seen in a population result from characteristics passed from parent to offspring. Answer: B 17) A postulate is A) a set of four statements that confirm that evolution will occur. B) an idea that has been proven through scientific investigation. C) a statement accepted as true for the purposes of logical argument. D) a hypothesis. E) an educated guess. Answer: C 18) Which organism is LEAST likely to survive to reproduce? A) A dark-furred rodent that comes out only at night B) A plant that has a sweet flavor before it flowers C) A flower that produces a scent that attracts bees D) A shrub that produces a toxin in its flower buds that repels deer from eating it E) A seahorse that mimics the weeds in which it lives Answer: B

19) Genetic variations in natural populations develop due to A) individual activities. B) changes in the environment. C) random mutations of the DNA. D) environmental catastrophes. E) changes in diet. Answer: C 20) An antibiotic is given repeatedly to treat a recurrent ear infection. It worked initially but now is no longer effective. This indicates that the Streptococcus bacterium A) is infectious only if it is sensitive to the antibiotic. B) is very sensitive to theantibiotic. C) is being treated with an antibiotic that has experienced a manufacturing error, making it infective. D) experienced natural selection that has allowed the resistant Streptococcus to survive and multiply. Answer: D 21) Inheritable mutations in the genes of an individual arise due to A) random chance. B) environmental change. C) other species in the environment. D) vigorous exercise or effort. E) artificial selection. Answer: A 22) Which of the following statements about mutations is TRUE? A) Mutations almost always leave the organism worse off than before. B) Mutations are almost always better for the organism. C) Mutations are caused by naturalselection. D) Mutations occur at random and are by chance. E) Mutations have no effect on the survival and reproduction of an organism. Answer: D 23) Darwin realized that most species produce many more offspring than is necessary to maintain a constant population. The "excess" individuals in a population A) die before they can reproduce. B) evolve to become new species. C) mutate and are able to adapt to new environments. D) migrate to another location. Answer: A 24) Which of the four postulates of Darwin's theory of evolution was not well established when On the Origin of Species was first published but is overwhelmingly supported today? A) Individuals with advantageous traits survive longest and have the most offspring. B) Individuals in a population differ physically from one another in many ways. C) Some individuals in a population survive and reproduce better than do other individuals. D) Some differences among individuals in a population are due to genetics and are heritable. Answer: D

25) Which English economist predicted that the rapid growth of human populations would soon exceed Earth's capacity to support it? A) Wallace B) Lyell C) Hutton D) Mendel E) Malthus Answer: E 26) Darwin was influenced by Thomas Malthus's writings on A) uniformitarianism. B) population growth. C) evolution. D) genetics. E) natural selection. Answer: B 27) Some of Darwin's most important discoveries were based on studies of birds and tortoises that he observed in A) Tahiti. B) the Bahamas. C) the Galápagos Islands. D) Ecuador. E) Jamaica. Answer: C 28) Where are the Galápagos Islands? A) Near Southeast Asia B) Near the center of the south Atlantic Ocean C) Off the northwest coast of South America D) Off the west coast of North America E) Off the west coast of Australia Answer: C 29) The theory of natural selection states that A) random assortment of genes results in better physical characteristics in the following generations. B) all individuals live to reproduce in each generation. C) individuals that mutate in response to changes in their environment will contribute the most genes to the next generation. D) the most well-adapted individuals in their environments survive and reproduce, contributing the most genes to the nextgeneration. E) only the largest and strongest individuals survive. Answer: D 30) Natural selection can act on a certain trait only if the trait is A) morphological. B) heritable. C) new. D) favorable. E) behavioral. Answer: B

31) Which trait provides a survival advantage? A) A flower that attracts morebees B) A brightly colored fish that attracts predators C) A horse that lacks the ability to digest either grains or grass D) A shrub that loses the ability to make seeds E) A tree that grows shorter than the surrounding trees Answer: A 32) Natural selection is best described as A) the ability to generate new traits that better suit the species. B) working on the existing variation of traits to favor those better suited to the organism's environment. C) increasing the perfection of a species. D) causing the death of a significant proportion of the population. E) driving the species toward an eventual endpoint in which the species possesses the best possible adaptations for that particular environment. Answer: B 33) Boa constrictors have tiny pelvic girdles and leg bones inside their bodies. Because these structures are nonfunctional "evolutionary baggage," they are called A) homologous. B) convergent. C) analogous. D) vestigial. E) maladaptive. Answer: D 34) No one is certain what the function of the human appendix is. But, one thing we do know is that we can live without it, without noticeable consequences. Therefore, the human appendix is an example of a(n) A) homologous structure. B) vestigial structure. C) adaptation. D) mutation. E) analogous structure. Answer: B 35) Which of the following are vestigial structures? A) Wings of bats B) Hoofs of horses C) Pelvic bones of whales D) Vertebral columns in snakes E) Fish fins Answer: C 36) Some animal species found in caves have tiny, nonfunctional eyes. These are best described as A) analogous structures. B) vestigial structures. C) mutations. D) homologous structures. Answer: B

37) Humans still have body hair even though it is greatly reduced and serves little function. The hair is a(n) A) adaptation. B) analogous structure. C) homologous structure. D) mutation. E) vestigial structure. Answer: E 38) An emu is a flightless bird that still has wings. These wings are an example of A) analogous structures. B) homologous structures. C) adaptation. D) mutation. E) vestigial structures. Answer: E 39) The human upper arm bone (the humerus) is structurally similar to the upper wing bone of a bat. The structural similarity is an example of A) homologous structures. B) vestigial structures. C) adaptation. D) analogous structures. E) mutation. Answer: A 40) Sea squirts and lampreys, which are closely related aquatic animals, have a perforated pharynx, a ventral heart, and a notochord at some stage of development. These similarities are best explained by A) a common ancestry. B) inheritance of acquired characteristics. C) the "Ladder of Nature." D) artificial selection. E) uniformitarianism. Answer: A 41) Daisies and daffodils, have flowers that serve as organs of reproduction, leaves that serve as organs of photosynthesis, and xylem and phloem that move water and food throughout the plant. These similarities are best explained by A) the "Ladder of Nature." B) a common ancestry. C) inheritance of acquired characteristics. D) uniformitarianism. E) artificial selection. Answer: B 42) When unrelated organisms living under similar environmental demands evolve superficially similar structures, it is called A) coevolution. B) comparative anatomy. C) convergent evolution. D) superficial selection. Answer: C

43) Convergent evolution occurs when A) two or more different species evolve to become one species. B) analogous structures evolve to behomologous. C) two or more populations merge into one. D) unrelated organisms develop analogous structures. Answer: D 44) The fact that whales have pelvic and leg bones leads to the conclusion that A) ancestral whales had legs. B) they probably evolved from fish. C) having a pelvis is advantageous. D) whales should have functional legs. E) whales did not evolve by natural selection. Answer: A 45) Dolphins (which are mammals) and sharks (which are fish) have stiff dorsal fins projecting from their backs that help them maneuver through water. These relationships of structures to each other are best described as A) mutations. B) analogous structures. C) vestigial structures. D) homologous structures. Answer: B 46) Of all the possible amino acids, all living organisms make use of only the same 20 amino acids. This supports the idea that A) bacteria, animals, and plants developedindependently. B) only 20 amino acids exist on Earth. C) natural selection drives evolution. D) only a limited number of DNA mutations are possible. E) all living things are derived from a single common ancestor. Answer: E 47) Which of the following supports the idea that all organisms share a common ancestry? A) All cells use ATP as the template for protein synthesis. B) All cells use the same collection oflipids. C) All cells use DNA as a cellular energy carrier. D) All cells use amino acids as a carrier of genetic information. E) All cells have a similar biochemistry, including amino acids, nucleic acids, and ATP. Answer: E 48) Strong evidence for the common ancestry of all vertebrates is A) they all possess DNA. B) their means of reproduction. C) they all evolved from fish. D) the similarity of their embryologicalstages. E) they all have legs. Answer: D

49) Observations of a wide variety of vertebrate embryos suggest that A) fish are unrelated to other vertebrates because they are the only vertebrates that develop gills. B) chickens and humans are closely related because they lack substantial tails. C) fish, turtles, and mice are more closely related to one another than to either chickens or humans because they have substantial tails. D) all vertebrate species have similar genes for development. Answer: D 50) The amino acid sequences of human and chimpanzee hemoglobin are almost identical, yet they differ considerably from the sequence of the hemoglobin of dogs. This fact A) opposes the theory of evolution. B) neither supports nor opposes the theory of evolution. C) supports the theory of evolution. Answer: C 51) The amino acid sequences of human and bonobo hemoglobin are almost identical, yet they differ considerably from the sequence of the hemoglobin of wolves. This fact indicates that A) bonobos are more closely related to humans than to wolves. B) wolves and bonobos are closelyrelated. C) humans are more closely related to wolves than to bonobos. Answer: A 52) The controlled breeding of domestic plants and animals by humans to produce certain physical traits in those organisms is called A) physical selection. B) natural selection. C) agricultural selection. D) artificial selection. Answer: D 53) "Cole" refers to any of various plants belonging to the Cruciferae or mustard family, which include broccoli, cabbage, collard greens, and other familiar vegetables. The controlled breeding of cole crops to produce certain physical traits in those organisms is called A) artificial selection. B) natural selection. C) agricultural selection. D) physical selection. Answer: A 54) Which of the following is an example ofartificial selection? A) The many different breeds of domestic cats B) The many different species of Oak trees found in the forest. C) Green tree frogs that blend perfectly into their leafy surroundings D) Cheetahs that can outrun theirprey E) All of the above Answer: A

55) Charles Darwin believed that artificial selection was A) unimportant. B) a common phenomenon in nature. C) a process completely identical to natural selection. D) impossible. E) similar in many ways to natural selection. Answer: E 56) The many different breeds of domestic dog were produced by A) physical selection. B) natural selection. C) artificial mutation. D) artificial selection. Answer: D 57) Imagine that a biologist develops a strain of corn with a lower fat content by choosing low-fat variants and crossbreeding them over several generations. This is an example of A) inheritance of acquired characteristics. B) convergent evolution. C) natural selection. D) artificial mutation. E) artificial selection. Answer: E 58) Most commercial pesticides are effective for only 2 or 3 yearsbecause A) those pests born with mutations that provide immunity will survive and reproduce. B) the chemicals induce mutations that provide immunity. C) the pests learn to hide when the chemicals are being applied. D) the chemicals mutate and become ineffective. E) new pests invade the area. Answer: A 59) A farmer noticed that two of her cotton plants produce cotton with a slight greenish hue. By repeatedly crossing the greenish plants, she has produced a variety of deep-green cotton without the use of any dyes. This is an example of A) convergent evolution. B) natural selection. C) artificial mutation. D) artificial selection. E) inheritance of acquired characteristics. Answer: D 60) A farmer produces a variety of apple with deep pink flesh by selectively crossbreeding apples with pinkish hues. This is an exampleof A) convergent evolution. B) natural selection. C) artificial mutation. D) artificial selection. E) inheritance of acquired characteristics. Answer: D

61) Dandelions in a lawn that is mowed have short flower stalks, whereas those in a field have tall flower stocks. This illustrates A) convergent evolution. B) natural selection. C) artificial mutation. D) artificial selection. E) inheritance of acquired characteristics. Answer: B 62) Which of the following would you predict would evolve in guppies that are taken from streams in Trinidad with predators and put into streams lacking predators? A) Guppies would evolve to have females prefer less colorful males. B) Guppies would evolve to have females avoid more colorful males. C) Male guppies will become less colorful. D) Male guppies will become more colorful. E) Male guppies will not change in coloration. Answer: D 63) Anolis lizards can be informally subdivided into long-legged forms (which move by jumping from tree to tree) and short-legged forms (which mostly crawl from one area to another). Both forms are usually found in any population. A group of Anolis lizards with long legs are transplanted from an island with many large trees to an island with many small plants and no trees. In future generations, the transplanted lizard population is most likely to A) evolve shorter legs adapted for the smaller plants. B) evolve to be able to run away from predators more quickly. C) undergo no evolutionary change. D) evolve to be able to maneuver less efficiently. E) evolve even longer legs. Answer: A 64) Based on the way natural selection works, what is the best way to make use of antibacterial soap? A) Never use it because bacteria will evolve to become resistant to it. B) Always use it because most bacteria will cause illness. C) Always use it because it is unlikely that bacteria will evolve to become resistant to it. D) Use it only when you need to be free of bacterial contamination, so bacteria will be less likely to evolve resistance to it. E) Never use it because all bacteria are harmless. Answer: D 65) Evidence that supports the theory of evolution is found in the studies of A) fossils. B) biochemistry. C) embryos. D) embryos, biochemistry, fossils, and artificial selection. E) artificial selection. Answer: D 66) In most geological formations, younger rocks are layered over older rocks. A) True B) False Answer: A

67) If a woman learns to speak many languages, her children will inherit fluency in many languages. A) True B) False Answer: B 68) There were biologists before Darwin who proposed mechanisms for evolution. A) True B) False Answer: A 69) Darwin's theory of evolution was based on his observations during his voyage to Asia. A) True B) False Answer: B 70) In any evolving population of organisms, individual variations exist. A) True B) False Answer: A 71) In theory, individuals with advantageous traits are more likely to reproduce. A) True B) False Answer: A 72) Insects and bats both have wings. This proves they evolved from a common ancestor. A) True B) False Answer: B 73) Early in embryonic development, all vertebrate embryos have some similarities in their appearance. A) True B) False Answer: A 74) Through artificial selection, it is possible to select for characteristics that may not be advantageous to the organism in a natural environment. A) True B) False Answer: A SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 75) Coprolites (animal dung), bones, and impressions of body parts in rocks are called

Answer: fossils 76) The theory that earthquakes, floods, and other natural disasters cause extinctions of some species while leaving others unharmed is . Answer: catastrophism

77) Darwin and

both developed and proposed the theory of evolution by natural selection.

Answer: Wallace 78) Variations in a population are produced by

Answer: chancemutations 79) Mammalian appendages with similar bone structures can be used for flying, swimming, running, or grasping. These are examples of structures. Answer: homologous 80) Pelvic bones in snakes and whales are

structures.

Answer: vestigial 81) The wings of insects and bats are

structures.

Answer: analogous 82) A bat's wing and a sheep's front leg are

structures.

Answer: homologous 83) The large, productive udders of domesticated milk goats and cows are structures that have arisen through . Answer: artificial selection 84) How does the fossil record support the theory of evolution? Answer: In a geological formation, the youngest rocks are most often at the surface. Moving deeper through the strata, the rocks become progressively older. Fossils can be dated based on the rock layer in which they are found. Fossils from one layer to the next show gradual changes, becoming more similar to modern species in the younger rocks. 85) How does Lamarck's proposed method of evolution differ from Darwin's? Answer: Lamarck proposed that individuals adapted. Modifications an individual made were passed to the offspring. Darwin's theory dealt with variations in a population. Those variations that provided an advantage to individuals in the population enabled those individuals to reproduce and pass those advantageous traits on to their offspring. 86) Neither Wallace nor Darwin discussed genes when describing natural selection. Why? Answer: Neither genes nor DNA had been identified at that time. Wallace and Darwin understood that traits were passed from generation to generation but did not understand the mechanism. 87) Provide three types of evidence (from different subdisciplines in biology) that scientists commonly use to provide support for the theory of evolution. Answer: Fossils, comparative anatomy, embryological similarity, and modern biochemical and genetic analyses are four possible answers. 88) What biochemical clues support the idea that all living things evolved from one common ancestor? Answer: All cells identified to date use DNA for carrying genetic information, use RNA for protein synthesis, use ATP as a cellular energy carrier, and build proteins from the same 20 amino acids.

89) A hospital uses a new cleaner to disinfect surfaces. Within a few years, many patients are developing infections from a bacterium that is resistant to the disinfectant. How does this happen? Answer: All populations contain genetic variation. By random chance mutation, some bacteria have the ability to resist the disinfectant. The other bacteria are sensitive and die. This gives the resistant bacteria a survival advantage. Over time, the population of bacteria evolves to contain large numbers of resistant organisms. 90) A population of grasshoppers in the Kansas prairie has two color types: green and brown. Typically, the prairie receives enough rainfall to maintain healthy, green grass. Assume a bird species that eats grasshoppers moves into the prairie. How will this affect the natural selection of the grasshoppers? How might this change in a drought year, when the grass turns brown? Answer: The brown phenotype may be more easily detected by the bird predator and decrease in frequency when the prairie is green. The opposite may be true in drought years when the green phenotype is more visible. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 91) The figure indicates that

A) trilobites, seed ferns, and dinosaurs evolved at the same time. B) trilobites ate seed ferns. C) seed ferns evolved before trilobites. D) trilobites evolved before seed ferns. E) dinosaurs evolved before trilobites. Answer: D

92) A storm blows the four species of finches shown in the figure to a new island that has only small-seeded grasses. Which species is more likely to survive?

A) Species a B) Species b C) Species c D) Species d Answer: B 93) A man spends his lifetime perfecting his painting skills. He has his daughter paint as well. He expects his grandson to be a world-famous painter. Whose theory is this man using? A) Cuvier's B) Buffon's C) Darwin's D) Lamarck's E) Lyell's Answer: D

94) Assume it is possible to remove continuous cores of rock from Earth that are 3,000 feet long and contain fossils. What would the theory of evolution by natural selection predict about the fossils found in such cores as they are examined from top tobottom? A) Higher fossils are more similar to living species than to lower fossils. B) Lower fossils are more similar to living species than to higher fossils. C) Fossil forms are arranged in random patterns. D) Fossil species remain constant from top to bottom. E) The number of fossils decreases from top to bottom, but the number of species increases. Answer: A 95) Fish in a local lake have a mixture of brown and green scales and are found throughout the lake. Over a 5-year period, the lake develops more plant growth and an exotic predatory frog is introduced. What change would you expect to see in the original fish population? A) Brown-scaled fish will become morecommon. B) Fish that prefer the unvegetated areas of the lake will become more common. C) No visible changes will occur in the fish population. D) The fish with green scales will become more common. E) The fish will develop to resemble the introduced frog. Answer: D 96) Imagine that a population of deer living on an island without any predators was threatened with overpopulation, until wolves were imported. After a couple of years, there were fewer deer, but their average running speed and the length of their legs had increased. What process accounts for the change? A) Changes due to chance alone B) Genetic impossibility C) Natural selection D) Inheritance of acquired characteristics E) Unfavorable mutations Answer: C 97) If the weather in Virginia changed so dramatically that there was snow on the ground most of the year, what would occur in the local squirrel population? A) If a mutation occurred that caused white fur to develop, such white squirrels would likely survive and reproduce better than gray squirrels. B) Natural selection could not change the population of squirrels in response to such climatic changes. C) The change in the weather would cause a mutation that makes their fur white, resulting in white squirrels that survive and reproduce better than gray squirrels. D) Natural selection would cause a new gene to appear in the population, resulting in squirrels growing white fur when there is snow on the ground and growing gray fur at other times. E) Evolution would produce white squirrels because white squirrels survive and reproduce better than squirrels of any other color. Answer: A

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Which of the following can evolve? A) Individuals B) Populations C) Communities D) Genes Answer: B 2) A population is defined as A) all individuals of all species located in a given country. B) all individuals of all species located throughout the world. C) all individuals of the same species located throughout the world. D) those individuals of the same species that have an identical genetic makeup. E) all individuals of the same species located in a given geographic region. Answer: E 3) The allele frequency of a population is the A) number of different types of alleles in that population. B) number of all alleles in that population. C) relative proportion of a given allele in that population. D) sum of all genes in that population. Answer: C 4) The interaction of genes and environment produces a specific A) population. B) genotype. C) allele. D) phenotype. E) gene pool. Answer: D 5) The gene pool for a particular population is made up of A) all the genes for a certain trait that occur in the population. B) all the alleles for a certain trait in a given individual. C) the sum of all the heterozygous individuals in the population. D) the sum of all the homozygous individuals in the population. E) all the genes that occur in the population. Answer: E 6) In a very small population of birds, assume 5 out of 20 alleles are the type that codes for blue feathers. What is the allele frequency of the "blue feather allele" in this population? A) 0.20 B) 0.25 C) 0.40 D) 5 E) 0.50 Answer: B

7) Evolution can be defined as A) a change in the phenotype of an individual over his or her lifetime. B) one species diverging into twospecies. C) an individual changing into anotherspecies. D) a change in the genetic makeup of an organism over time. E) a change in the genetic makeup of a population over time. Answer: E 8) Populations of organisms are constantly evolving, which means that they are always A) becoming more like humans. B) improving. C) changing. D) at equilibrium. E) getting bigger. Answer: C 9) Within a large population, if no mutations occur, no migration occurs, all matings are random, and each individual has an equal chance of reproducing, which of the following will probably happen? A) A bottleneck will occur. B) Extinction will result. C) A change in allele frequency will lead to rapid evolution. D) Natural selection will occur at the normal rate for that species. E) No evolution willoccur. Answer: E 10) In the context of evolution, equilibrium means A) equal numbers of all alleles. B) no individuals move into or out of the population. C) no change in allele frequency. D) equal numbers of males andfemales. E) no change in population size. Answer: C 11) In an equilibrium population A) population size cannot change. B) natural selection occurs. C) mutation rates do not change. D) rates of gene flow are constant. E) allele frequencies do not change. Answer: E 12) According to the Hardy-Weinberg principle, if 75% of the alleles in the gene pool are A1 and 25% are A2, what is the proportion of individuals with genotype A1A2 in this population? A) 0.0625 B) 0.025 C) 0.375 D) 0.5625 E) 0.1875 Answer: C

13) A population carries two alleles for a trait in which T is dominant and t is recessive. In the Hardy-Weinberg equation, 2pq represents the A) proportion of homozygous dominant individuals. B) decrease in heterozygous individuals. C) proportion of homozygous recessive individuals. D) increase in homozygous individuals. E) proportion of heterozygous individuals. Answer: E 14) A population carries two alleles for a trait in which T is dominant and t is recessive. In the Hardy-Weinberg equation, p2 represents the A) proportion of homozygous dominant individuals. B) decrease in heterozygous individuals. C) proportion of homozygous recessive individuals. D) increase in homozygous individuals. E) proportion of heterozygous individuals. Answer: A 15) A population carries two alleles for a trait in which T is dominant and t is recessive. In the Hardy-Weinberg equation, q2 represents the A) proportion of homozygous dominant individuals. B) decrease in heterozygous individuals. C) proportion of homozygous recessive individuals. D) increase in homozygous individuals. E) proportion of heterozygous individuals. Answer: C 16) Imagine that one of the original four mice that escape from a research lab is blind due to a genetic defect. If the escaped mouse breeds and most of the mice born in subsequent generations are blind from birth, this is most likely a case of A) natural selection. B) an equilibrium population. C) selective mutation. D) the foundereffect. E) artificial selection. Answer: D 17) Which of the following can cause evolutionary change in a small population? A) Lack of mutations B) Genetic drift C) Lack of gene flow D) All recessive alleles E) Homozygous individuals Answer: B

18) Which of the following is most likely to experience genetic drift? A) A population of endangered birds that includes only five individuals B) A population of bears that is growing by thousands of individuals each year C) A population of common rodents that includes millions of individuals D) A species of insect that occurs all across North America E) A plant species that has spread to many different habitats all around the world Answer: A 19) Inbreeding is defined as A) reproduction within a geographically isolated population. B) sexual population among unrelated individuals. C) sexual reproduction among closely relatedindividuals. D) reproduction among unrelated individuals. E) sexual reproduction in a large population. Answer: C 20) A young male baboon leaves the troop that he was born in and joins a small neighboring troop of small baboons. He quickly rises to become a dominant male. From an evolutionary point of view, what important process has occurred? A) The bottleneck effect B) Natural selection C) Genetic drift D) Gene flow E) Nonrandom mating Answer: D 21) Zoos often loan animals to other zoos for breeding purposes. From an evolutionary standpoint, what is the benefit? A) New animals increase zoo revenues. B) It increases the genetic diversity of the zoo's population. C) It increases the rate of random mutations. D) It increases the effects of natural selection on the population. E) It creates a bottleneck effect. Answer: B 22) The 30,000 elephant seals alive today are genetically very similar due to A) the bottleneck effect. B) the foundereffect. C) artificial selection. D) natural selection. E) random mutation. Answer: A 23) Habitat loss, natural catastrophes, and/or excessive harvesting of a species often result in A) increased fitness of individuals. B) increased gene flow. C) population bottlenecks. D) artificial selection. E) increased mutation rates. Answer: C

24) Which of the following mutations would increase evolutionary fitness? A) One that attracts more potential mates without increasing the frequency of reproduction B) One that increases the life span of the organism C) One that increases the frequency of successful reproduction D) One that increases the birth weight of offspring while decreasing the number of offspring E) One that removes other alleles from the population Answer: C 25) The process by which allele frequencies are altered in a small population due to chance is called A) assortative evolution. B) fitness. C) random evolution. D) genetic drift. E) random mutation. Answer: D 26) Mutations A) arise due to environmental pressures. B) are caused by natural selection. C) limit the potential for evolution. D) can be helpful, neutral, or harmful to individuals. Answer: D 27) Mutations are important because they A) usually provide an individual with increased reproductive rates. B) are always beneficial to the individuals affected by them. C) occur in response to environmental demands. D) provide variation that can result in evolutionary change. Answer: D 28) Gene flow A) prevents migration of individuals into other populations. B) negates the influence of evolution on a population. C) can spread certain alleles throughout a species. D) limits evolutionary fitness. E) isolates populations from one another. Answer: C 29) In general, each species of fruit fly in the Hawaiian archipelago is restricted to a single island. One hypothesis to explain this pattern is that new species formed after a small number of flies colonized each new island. This mechanism of speciation is called A) the founder effect. B) sexual selection. C) genetic equilibrium. D) assortative mating. E) artificial selection. Answer: A

30) Imagine a population of monkeys in South America whose habitat has been reduced to the point where only 20 individuals survive. This is an example of A) sexual selection. B) natural selection. C) the founder effect. D) a population bottleneck. E) genetic drift. Answer: D 31) Genetic drift results in a change in allele frequencies because A) gene flow within the population allows alleles to flow between populations. B) the population has not yetstabilized. C) the population is so large that natural selection has little noticeable effect. D) the population size is so small that chance occurrences can alter allele frequencies. Answer: D 32) Evolution by genetic drift is most obvious in A) invertebrate species. B) migratory species. C) aquatic organisms. D) large populations. E) small populations. Answer: E 33) Shrews have been documented to travel across frozen lakes and establish populations on previously uninhabited islands. The low level of genetic diversity in the new populations is the result of A) coevolution. B) geneticdrift. C) the founder effect. D) a population bottleneck. E) assortative mating. Answer: C 34) The Pennsylvania Amish have a very high frequency of an unusual allele that results in short arms and legs and extra fingers. This high frequency is thought to be the result of A) coevolution. B) the addition of new members to an already established population. C) a population bottleneck. D) nonrandom mutations. E) the founder effect. Answer: E 35) The extreme loss of genetic diversity that has occurred in cheetah populations due to overhunting is the result of A) the founder effect. B) a population bottleneck. C) coevolution. D) natural selection. E) genetic drift. Answer: B

36) Which of the following is an example of assortative mating? A) A female sheep chooses a mate because he has previously mated with many females. B) A female mouse chooses a mate because he is the same color that she is. C) A dominant male elephant mates with most females in a group, excluding other males from mating with the females. D) A female sparrow chooses a mate because he attracts her by singing a different species' song. E) A female lizard chooses to mate with the first male she encounters. Answer: B 37) Which of the following can be measured to estimate an organism's evolutionary fitness? A) The number of gametes it produces over its lifetime B) The number of eggs it produces over its lifetime C) The number of offspring it produces over its lifetime D) The number of offspring it produces over its lifetime that survive to breed E) The size of its offspring Answer: D 38) A bacterial allele that provides resistance to the antibiotic streptomycin is A) always detrimental to the cell. B) beneficial to the cell in the presence of any antibiotic. C) always beneficial to the bacterial cell. D) beneficial to the cell in the presence of streptomycin. E) neither beneficial nor detrimental to the cell. Answer: D 39) Having greater evolutionary fitness means A) being better able to survive. B) being larger or faster. C) being stronger. D) being able to produce more sperm or eggs. E) having more offspring. Answer: E 40) Male fish that display a bright blue color attract more mates as well as more predators. Maintaining that blue gene in the population is an example of A) sexual selection. B) geneticdrift. C) coevolution. D) the founder effect. E) a population bottleneck. Answer: A 41) If the tallest and shortest individuals of a population of humans do not survive and reproduce as well as the individuals of "average" height, which type of selection would most likely result? A) Stabilizing selection B) Artificial selection C) Directional selection D) Disruptive selection Answer: A

42) In a certain species of salmon, some adult males are extremely large whereas other adult males are very small, compared to the females. There are no intermediate-sized adult males in the population. This is probably the result of A) artificial selection. B) directional selection. C) stabilizing selection. D) disruptive selection. Answer: D 43) In one butterfly species, the colors of individuals range from white to black, with many shades of gray in between. If the butterflies in a mountain population become more and more similar in color over several generations (e.g., if most butterflies are the same shade of gray), what kind of evolutionary force is likely acting on the population? A) Artificial selection B) Directional selection C) Disruptiveselection D) Stabilizing selection Answer: D 44) Evolution by natural selection is A) constantly occurring at the same rate in all organisms. B) a rare event that has never been observed by scientists. C) a process that has occurred only in the past. D) a process that occurs as a result of differences in fitness. E) currently occurring but only in scientific laboratories. Answer: D 45) The elaborate courtship displays common among animals are the result of A) spontaneous mutations. B) disruptive selection. C) sexual selection. D) random mating. E) stabilizing selection. Answer: C 46) The male peacock's beautiful tail is really a trade-off between A) artificial selection and natural selection. B) sexual selection and natural selection. C) natural selection and genetic drift. D) disruptive selection and natural selection. Answer: B 47) Natural selection selects for or against certain A) phenotypes. B) alleles. C) populations. D) gene pools. E) genotypes. Answer: A

48) As predator and prey species acquire new adaptations to help them survive the constant "arms race" between them, what evolutionary phenomenon is occurring? A) Coevolution B) Geneticdrift C) Artificial selection D) Sexual selection E) Competition Answer: A 49) Female finches, which do not sing, often choose to mate with males that sing a specific, elaborate song. This is an example of A) fitness. B) sexual selection. C) assortative mating. D) inbreeding. E) coevolution. Answer: B 50) Members of one gender influence allele frequencies in a population by choosing mates according to some conspicuous feature in the other gender in the process called A) genetic drift. B) fitness. C) sexual selection. D) random evolution. E) random mutation. Answer: C 51) The change in one population driven by a change in an associated population is called A) coevolution. B) geneticdrift. C) fitness. D) random mutation. E) assortative evolution. Answer: A 52) Which trait is the best example of an adaptation? A) A longer tongue in an insect-eating mammal that feeds on insects that live in shallow burrows B) A shorter neck in a giraffe that lives in an area with many rival males and tall trees C) A new mutation that confers Tay-Sachs disease in humans D) A mutation resulting in a heat-resistant enzyme in a bacterium living in a hot spring E) A mutation resulting in weak branches in a species of tree that lives in windy regions Answer: D 53) The type of selection most likely to act on a well-adapted population in a relatively constant environment is A) directional. B) artificial. C) disruptive. D) stabilizing. E) nonrandom. Answer: D

54) When a species lives in a constant environment for a long time, the "average type" of individual may have the best chance of surviving and producing the most offspring. What type of selection is occurring? A) Directional B) Sexual C) Disruptive D) Stabilizing E) Artificial Answer: D 55) If two or more phenotypes in a population are both favored by selection, what is happening? A) Stabilizing selection B) Sexual selection C) Balanced polymorphism D) Directional selection E) Gene flow Answer: C 56) In some butterfly populations, there are equal frequencies of alleles that code for black and yellow coloration. This is an exampleof A) nonrandom mutations. B) directional selection. C) balanced polymorphism. D) sexual selection. E) stabilizing selection. Answer: C 57) A new predator is introduced to an area that can feed on any millipedes shorter than 200 millimeters. No millipedes that live in that area are longer than 15 millimeters. What will happen? A) The millipedes will necessarily mutate to be longer. B) All millipedes will be potential prey. C) Directional selection will favor predators that consume the smallest millipedes. D) Disruptive selection will favor 15-millimeter-longmillipedes. E) Millipedes will necessarily evolve to avoid the predator. Answer: B 58) A flock of birds with various beak sizes migrates to a new island where their traditional food is not available. However, there are plants that produce a variety of large nuts, which can be eaten by birds with the largest beaks, and plants that produce a variety of small, soft seeds, which can be eaten by birds with the smallest beaks. Over time, this population divides into two species with large and small beaks. This is an example of A) directional selection. B) stabilizing selection. C) disruptive selection. D) sexual selection. E) genetic drift. Answer: C

59) A population of hummingbirds with a variety of beak sizes finds a new food source in a plant that has a long trumpet flower with nectar at the bottom of the trumpet. Over time, these hummingbirds develop longer beaks. This is an exampleof A) directional selection. B) stabilizing selection. C) disruptive selection. D) sexual selection. E) genetic drift. Answer: A 60) Suppose a new mutation that improves metabolic efficiency is lost from a small population of mammals living in a region of seasonal food scarcity after a hurricane eliminates half the mammal population. This is an example of A) directional selection. B) stabilizing selection. C) disruptive selection. D) sexual selection. E) genetic drift. Answer: E 61) Suppose a population of mostly sand-colored crabs migrates from a sand beach to a pebble beach and evolves a darker, speckled coloration that closely resembles the pebble beach. This is an example of A) directional selection. B) stabilizing selection. C) disruptive selection. D) sexual selection. E) genetic drift. Answer: A 62) Imagine that a mutation for red eye color becomes very common in a population of flies because female flies in this population prefer to mate with red-eyed males. This is an example of A) directional selection. B) stabilizing selection. C) disruptive selection. D) sexual selection. E) genetic drift. Answer: D 63) When different species closely interact for an extended period of time and develop new adaptations in response to each other, it is called A) gene flow. B) genetic drift. C) sexual selection. D) stabilizing selection. E) coevolution. Answer: E

64) Which of the following phenomena favors individuals with average phenotypes over those with extreme phenotypes? A) Gene flow B) Genetic drift C) Sexual selection D) Stabilizing selection E) Coevolution Answer: D 65) The bright coloration of male birds is often the result of A) gene flow. B) genetic drift. C) sexual selection. D) stabilizing selection. E) coevolution. Answer: C 66) Bright coloration in birds makes them stand out to predators. In female birds that sit on the nest, bright coloration is rare. This is likely the result of A) coevolution. B) artificial mutations. C) stabilizing selection. D) gene flow. E) natural selection. Answer: E 67) The net migration of alleles into or out of a population from neighboring populations is called A) gene flow. B) genetic drift. C) sexual selection. D) stabilizing selection. E) coevolution. Answer: A 68) Which of the following occurs due to chance events that change the allele frequencies in small populations? A) Gene flow B) Genetic drift C) Sexual selection D) Stabilizing selection E) Coevolution Answer: B 69) When one species evolves a new phenotypic feature and another species evolves new adaptations in response, it is called A) gene flow. B) genetic drift. C) sexual selection. D) stabilizing selection. E) coevolution. Answer: E

70) When natural selection tends to split a population into two phenotypic groups, it is called A) balanced polymorphism. B) gene flow. C) genetic drift. D) stabilizing selection. E) coevolution. Answer: A 71) The nonliving components of an environment, such as weather and water availability, are A) abiotic components. B) phenotypes. C) biotic components. D) alleles. E) genotypes. Answer: A 72) Multidrug-resistant bacteria A) are becoming less widespread. B) are becoming more widespread. C) have always been common in the natural environment. D) have been eradicated worldwide. E) are not serious threats to human health. Answer: B 73) Which of the following can affect a small, endangered population so severely that it goes extinct? A) Artificially adding new genes B) Matings with a closely relatedspecies C) Sexual selection D) Increased mating opportunities E) Lost alleles and/or low genetic diversity Answer: E 74) In a population, the most common phenotype represents the dominant allele. A) True B) False Answer: B 75) Gene flow results when new individuals migrate into an area and join the breeding population there. A) True B) False Answer: A 76) In a single family, the parents have brown eyes but all five of their children have green eyes. This is an example of evolution. A) True B) False Answer: B

77) Genetic drift is more common in large populations than in small populations. A) True B) False Answer: B 78) Organisms that have the greatest reproductive success are considered the most evolutionarily fit. A) True B) False Answer: A 79) The use of antibiotics caused the mutation that produced methicillin-resistant Staphylococcus aureus (MRSA). A) True B) False Answer: B 80) Natural selection causes genetic changes in populations. A) True B) False Answer: A 81) Natural selection causes genetic changes in an individual. A) True B) False Answer: B 82) Environmental change causes the heritable variations in individuals that natural selection acts upon. A) True B) False Answer: B 83) A bird comes in a range of phenotypes, from white through gray to black. Disruptive selection favors the gray phenotype. A) True B) False Answer: B SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 84) According to the mathematical equation used in the Hardy-Weinberg principle, if the alleles for a certain trait in a population are A1 and A2, then the proportion of individuals with the genotype is represented by 2pq. Answer: A1A2 85) Evolution occurs in

Answer: populations 86) Individuals who have one dominant allele and one recessive allele for a trait are referred to as Answer: heterozygotes

87) Antibiotic resistance is a result of

in bacteria.

Answer: naturalselection 88) Evolution can be defined as change in

in a population.

Answer: allelefrequencies 89) A population with

is at risk for extinction.

Answer: limited genetic variability 90) Suppose a small population of deer is introduced to an island. All of the original males have 6 to 10 points on their antlers, and the average male has 8 points. After several generations, if most males have antlers with 10 points and no males have 6 points, the population has undergone selection. Answer: directional 91) A population that maintains several different phenotypes of the same trait displays

Answer: balancedpolymorphism 92) Natural selection acts on individual phenotypes to affect the evolution of

Answer: populations 93) What conditions are necessary for a population to be at equilibrium? Answer: There can be no mutations, no gene flow, only random matings, no natural selection, and a large population. 94) What causes evolutionary change in a small population? Answer: Evolutionary change in small populations can result from genetic drift, random mutations, and natural selection. 95) A city was intensively sprayed with the chemical DDT to control houseflies. The number of houseflies was immediately greatly reduced. Each year thereafter, the city was sprayed again, but the flies gradually increased in numbers until 10 years later when they were as abundant as they were before the control program began. Provide an evolutionary explanation of what happened. Answer: The few flies that happened to be born with a genetic resistance to DDT survived and then passed this resistance on to their offspring. Subsequent generations of flies were less and less affected by DDT, and natural selection resulted in a population resistant to the chemical that could proliferate even when DDT was applied. 96) Evolutionary adaptations are not always the "best" solution to a problem. Explain how the long necks of giraffes can be both advantageous anddisadvantageous. Answer: The long neck provides an advantage to males when battling for dominance and feeding on the leaves of tall trees. However, when drinking water from a pool, the giraffe is in a very awkward position and at a disadvantage because it is vulnerable to attack by predators. 97) How does the founder effect influence the frequency of alleles in a population? Answer: The alleles carried by the founding population are the only alleles available in the population unless mutation occurs or new individuals migrate to the area. If an allele is not present in the founding population, subsequent generations will not display that trait. For example, if all individuals shipwrecked on an island were blood type O (a recessive trait), all of their descendants would be type O.

98) Explain why new mutations appear frequently in bacterial populations but infrequently in human populations. Answer: Bacterial populations reproduce rapidly and can produce hundreds of generations in much less time than it takes humans to produce a single generation. So, you can observe new mutations among bacteria before humans even have a next generation. 99) Explain how a recessive trait can be the most frequent phenotype in a population. Answer: The population's environment can drive directional selection, which could favor the organisms expressing the recessive trait while removing the dominant phenotype from the gene pool. 100) Explain how disruptive selection could lead to the development of two species from one original founding population. Answer: Disruptive selection favors the extreme phenotypes of a population. Over time, this could lead to organisms so different that they are no longer able to reproduce with each other.

101) In the population shown in the figure, what is the most common fur color allele in this population? Answer: allele b

102) In hamsters, the dominant allele B codes for a black coat and the recessive allele b codes for a tan coat. In the population shown in the figure above, what is the most frequent phenotype? Answer: black coat MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

103) Based on the information shown in the figure, what do you predict the fourth generation will look like?

A) All the hamsters will betan. B) Five hamsters will be black. C) There is no way to predict what the fourth generation will look like. D) All the hamsters will have mottled tan/black fur. E) All the hamsters will be black. Answer: A 104) A population of plants comes in two flower colors: blue and white. Crossing two blue-flowered plants produces mostly blue-flowering offspring and some white-flowering offspring. Crossing two white-flowered plants produces only white-flowering offspring. This indicates that the white-flowering plants are A) mutating. B) homozygous dominant for the flower color allele. C) heterozygous for the flower color allele. D) in equilibrium. E) homozygous recessive for the flower color allele. Answer: E 105) Suppose that the only remaining population of a certain reptile species lives on an African mountain and that there is no migration out of this large but isolated population. Which of the following describes the most likely future of this reptile population? A) The population will survive only as long as the environment remains constant. B) Evolution will promptly cease. C) The population will go extinct after a few generations because of inbreeding. D) Evolution will continue because of mutations, assortative mating, and genetic drift. E) The bottleneck effect will cause major evolutionary changes in the isolated population. Answer: D 106) Imagine that two men and two women settle on an uninhabited island, no new settlers arrive, and nobody leaves the island for many generations. All four of the settlers have brown eyes, but one of the men carries a recessive gene for blue eyes. Eye color has no effect on fitness. If the percentage of blue-eyed individuals on the island increases from 0% to 25%, what is the probable cause? A) Natural selection B) Random mutation C) Artificial selection D) Genetic drift Answer: D 107) The fish in a certain population average 10 millimeters in length. Imagine that a population of predatory birds arrives in the area, but they cannot eat fish longer than 15 millimeters. After a decade, if the fish average 14 millimeters in length, what probably happened? A) There was disruptive selection for fish length. B) There was stabilizing selection for fish length. C) The longer fish survived and produced more offspring than shorter fish. D) The presence of the predator caused mutations for larger fish to occur. E) The fish and the predator coevolved. Answer: C

108) Despite causing a life-threatening disease, the sickle-cell allele in some areas of Africa has remained in high frequency in those populations because it protects against malaria. In the United States, malaria was eradicated shortly before World War II by eliminating the mosquito that spreads the disease. What is likely to happen to the frequency of the sickle-cell allele in African Americans living in the United States? A) The sickle-cell allele will disappear from the African American population. B) The normal allele will disappear from the African American population. C) The frequency of the sickle-cell allele will not change. D) The frequency of the sickle-cell allele willincrease. E) The frequency of the sickle-cell allele will decrease. Answer: E 109) In central Africa, the frequency of the sickle-cell allele has remained stable over the years because the allele protects against malaria. In the United States, malaria was eradicated by eliminating the mosquito that spreads the disease. The decreasing frequency of the sickle-cell allele in African Americans since malaria was eliminated in the United States is an example of A) the founder effect. B) directional selection. C) stabilizing selection. D) genetic drift. E) disruptive selection. Answer: B

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Two populations of plants look identical but their flowers are fertilized by different pollinators-one by a night-flying hummingbird moth, the other by honeybees. These two populations of flowers are examples of A) identical gene pools. B) the same species using differentpollinators. C) different species. D) groups within the same species. E) identical evolutionary paths. Answer: C 2) Before the modern era of science, organisms were assigned to species on the basis of A) geographic location. B) behavioral similarities. C) the existence of fossils of earlier forms. D) similarities in appearance. E) their capability of interbreeding. Answer: D 3) A group of an interbreeding natural population that is reproductively isolated from other such groups is called a A) community. B) species. C) genotype. D) tribe. E) genus. Answer: B 4) The biological concept of species requires that A) individuals are able to reproduce outside the group. B) geographic isolation occurs. C) organisms reproduce sexually. D) organisms are morphologically similar. E) only asexual reproduction occurs. Answer: C 5) The biological species concept cannot be applied to A) species resulting from adaptive radiation. B) sympatric populations. C) extinct organisms. D) polyploid populations. E) allopatric populations. Answer: C 6) Populations that were once considered separate species are sometimes reassigned to the same species because A) it was discovered that they can produce viable and fertile offspring. B) they are no longer capable of interbreeding. C) they have evolved to look different from each other. D) they have been found to be genetically identical. E) they have evolved to look the same. Answer: A

7) Two fossils may be assigned to different species if A) they show no evidence of being capable of interbreeding. B) they are anatomically different. C) they come from different places. D) one appears to be ancestral to the other. E) they come from different time periods. Answer: B 8) Fruit fly species all look similar to one another. If you have a male and a female fruit fly, how can you prove that they are the same species, according to the biological species concept? A) If they mate when they are put together, they are the same species. B) If they can asexually reproduce and their offspring can also successfully asexually reproduce, they are the same species. C) Examine them closely with a low-power microscope, comparing their physical characteristics to published species key lists of characteristics. D) If they mate successfully and their offspring are fertile, they are the same species. E) Determine the base sequence of the DNA of their chromosomes. Answer: D 9) Which of these definitions of species best matches the biological species concept? A) Members of the same species are whatever an expert says they are. B) Members of the same species are all genetically identical. C) Members of the same species are all morphologically similar. D) Members of the same species look almost exactly alike. E) Members of the same species can mate and produce fertile offspring. Answer: E 10) Two populations of plants found in the same meadow look identical but are fertilized by different pollinators-one by a night-flying hummingbird moth, the other by honeybees that fly by day. This is an example of A) behavioral isolation. B) temporal isolation. C) mechanical incompatibility. D) ecological isolation. E) geographicisolation. Answer: B 11) One species of fish feeds in the muddy bottom of a lake. A second species eats insects that land on the water surface. This is an exampleof A) ecological isolation. B) temporal isolation. C) geographic isolation. D) behavioralisolation. E) mechanical incompatibility. Answer: A

12) Two species of snails are physically unable to mate. This is an example of A) behavioral isolation B) temporal isolation. C) mechanical incompatibility. D) geographic isolation. E) ecological isolation. Answer: C 13) Two different species of pine release their pollen at different times of the year. This is an example of A) geographic isolation. B) ecological isolation. C) behavioral isolation. D) mechanical incompatibility. E) temporal isolation. Answer: E 14) Two species of garter snakes live in the same geographic area. One lives mainly in water and the other mainly on land; therefore, they rarely encounter each other and do not interbreed. What type of isolation is this? A) Behavioral B) Geographic C) Temporal D) Ecological E) Mechanical Answer: D 15) Female blue-footed boobies of the Galápagos Islands will mate only after a specific courtship display on the part of the male. The male high-steps to advertise his bright blue feet. What mechanism describes why the females do not mate with other species of boobies? A) Geographic isolation B) Behavioral isolation C) Temporal isolation D) Mechanical incompatibility E) Ecological isolation Answer: B 16) Two species of pines, Pinus radiata and Pinus muricota, live in the same regions of California and are capable of forming hybrids under laboratory conditions. However, they do not interbreed because one releases pollen in February and the other in April. What genetic isolating mechanism is involved? A) Ecological B) Temporal C) Hybrid inviability D) Geographic E) Gametic Answer: B

17) In many species of fireflies, males flash light from their abdomens to attract females. Each species has a different flashing pattern. This is an example of A) behavioral isolation. B) ecological isolation. C) temporal isolation. D) mechanical incompatibility. E) geographicisolation. Answer: A 18) Eastern and Western meadowlarks look almost identical and sometimes inhabit the same areas of prairies. These birds recognize members of their own species by distinctive songs and thus do not breed with each other. This is an exampleof A) mechanical isolation. B) geographic isolation. C) behavioralisolation. D) ecological isolation. E) temporal isolation. Answer: C 19) The elaborate courtship rituals of many bird species help to preserve their genetic isolation through A) temporal isolation. B) behavioral isolation. C) mechanical incompatibility. D) hybrid inviability. E) allopatric separation. Answer: B 20) One method of maintaining the genetic isolation of a population is the inability of sperm to fertilize eggs of a different species. This is called A) temporal isolation. B) behavioral isolation. C) hybrid inviability. D) gametic incompatibility. E) ecological isolation. Answer: D 21) The Great Dane and the Chihuahua are both domestic dogs (the same species), but mating between them is limited because of A) geographic isolation. B) hybrid inviability. C) hybrid infertility. D) behavioral isolation. E) mechanical incompatibility. Answer: E

22) Interbreeding two different species of lovebirds produces offspring that are unable to build a nest after they mature because they lack the appropriate nest-building behavior needed to build a nest. This limits genetic mixing between the speciesdue to A) geographic isolation. B) mechanical incompatibility. C) ecological isolation. D) hybrid inviability. E) behavioralisolation. Answer: E 23) Horses and donkeys can mate successfully to produce mules, which are always sterile. Which genetic isolating mechanism prevents horses and donkeys from becoming a single species? A) Hybrid infertility B) Mechanical isolation C) Hybrid inviability D) Temporal isolation E) Behavioral isolation Answer: A 24) If a hybrid is unable to produce sperm because meiosis does not proceed correctly, gene flow between the species is restricted by A) temporal isolation. B) ecological isolation. C) hybrid infertility. D) hybrid viability. E) gametic isolation. Answer: C 25) When offspring are infertile after breeding occurs between individuals of different species, the genetic identities of the two populations are protected by A) behavioral isolation. B) temporal isolation. C) mechanical incompatibility. D) hybrid infertility. E) genetic isolation. Answer: D 26) Lions and tigers can interbreed and produce offspring called tiglons or ligers, which have normal life spans but are sterile. Lions and tigers remain isolated genetically because of A) behavioral isolation. B) heterozygote disadvantage. C) mechanical incompatibility. D) hybrid infertility. E) hybrid inviability. Answer: D

27) Temporal isolation is an exampleof A) neither a premating nor a postmating isolation mechanism. B) a postmating isolating mechanism. C) both a premating and a postmating isolation mechanism. D) a premating isolating mechanism. Answer: D 28) Gametic incompatibility is an exampleof A) a premating isolating mechanism. B) hybrid inviability. C) a geographic isolating mechanism. D) a postmating isolatingmechanism. Answer: D 29) A pet store puts both Norway rats (Rattus norvegicus) and black rats (Rattus rattus) in the same cage. If mating occurs, the pregnancy will not succeed because the embryos fail to develop properly. This is an example of A) temporal isolation. B) hybrid inviability. C) hybrid infertility. D) hybrid vigor. E) gametic incompatibility. Answer: B 30) Crossing a zebra with a horse produces sterile offspring. This is an example of A) temporal isolation. B) hybrid inviability. C) hybrid infertility. D) hybrid vigor. E) gametic incompatibility. Answer: C 31) When some hybrid organisms do not live long, it is an example of A) temporal isolation. B) hybrid inviability. C) hybrid infertility. D) hybrid vigor. E) gametic incompatibility. Answer: B 32) When the pollen of one plant species will not germinate on the flower of another species, it is an example of A) temporal isolation. B) hybrid inviability. C) hybrid infertility. D) hybrid vigor. E) gametic incompatibility. Answer: E

33) When two organisms reach sexual maturity at different times, it is an example of A) temporal isolation. B) hybrid inviability. C) hybrid infertility. D) hybrid vigor. E) gameticincompatibility. Answer: A 34) Since the Pleistocene ice age, deserts have been gradually forming in the southwestern United States. As the original lakes and rivers of this area shrank into isolated streams, ponds, and springs, the fishes living in them developed a strong potential for A) mechanical incompatibility. B) speciation. C) temporal isolation. D) hybridization. E) hybrid inviability. Answer: B 35) Two species of squirrels live on either side of the Grand Canyon. It is believed that a long time ago, before being separated by the canyon, they were the same species. This is an example of A) behavioralisolation. B) mechanical isolation. C) temporal isolation. D) allopatric speciation. E) hybrid inviability. Answer: D 36) There are currently many similar-looking but different species on either side of the Isthmus of Panama. They most likely resulted from A) temporal isolation. B) hybridization. C) allopatric speciation. D) random mutations. E) sympatricspeciation. Answer: C 37) Where would a researcher most likely find examples of allopatric speciation? A) In a desert lacking sand dunes or rock formations B) On a mountain range with many steep valleys and turbulent rivers C) On the surface of a large lake D) In a large, flat prairie lacking any significant water E) At the bottom of a sandy, slowly flowing river Answer: B

38) What happens when two populations become geographically separated from each other and then genetic divergence occurs? A) The founder effect B) Continental drift C) Sympatric speciation D) Temporal isolation E) Allopatricspeciation Answer: E 39) The Kaibab squirrel lives on the north side of the Grand Canyon, and the Abert squirrel lives on the south side. Even though these two populations are only miles apart, their gene pools are kept isolated by A) hybrid infertility. B) ecological isolation. C) mechanical incompatibility. D) temporal isolation. E) geographicisolation. Answer: E 40) A horse has a diploid number (2n) of 64 and a donkey has 2n = 62. The hybrid of these two species, mules, have 2n = 63 and are sterile. Why are mules sterile? A) Mules are not true hybrids. B) One chromosome is unpaired and fails to divide properly during meiosis. C) Horses are not able to form new species. D) Mules cannot physically mate with each other. E) Mules cannot physically mate with horses and donkeys. Answer: B 41) The parasitic Rhagoletis flies show such a preference for either hawthorn or apple trees that they are no longer interbreeding populations. What type of speciation does this scenario illustrate? A) Sympatric B) Allopatric C) The founder effect D) Specialization E) Polyploidy Answer: A 42) Which statement best describes the reproductive isolation between populations of Rhagoletis flies, one of which is found on apple trees and the other that is found on hawthorn trees? A) Hybrid offspring of the two populations are sterile. B) Hawthorn trees and apple trees grow in different areas, so the two populations do not encounter each other. C) Apple-liking males are more likely to encounter apple-liking females than hawthorn-liking females. D) Male flies of one population cannot physically mate with females from the other population. E) Eggs laid by female flies mated with a male from the "wrong" population do not develop. Answer: C

43) When a species invades a new habitat and evolves rapidly into several new species to better exploit new resources, what has occurred? A) Adaptive radiation B) Extinction C) Genetic divergence D) Hybridization E) Polyploidy Answer: A 44) A single species of finch from South America was displaced to a new habitat in the Galápagos Islands and evolved rapidly into several new species as it exploited the new resources. What occurred in these Darwin's finches? A) Stabilizing selection B) Polyploidy C) Adaptive radiation D) Phyletic speciation E) Divergent speciation Answer: C 45) The origins of 300 or more species of cichlid fish in Lake Malawi can best be explained by A) random events. B) polyploidy. C) the fossil record. D) premating isolating mechanisms. E) adaptive radiation. Answer: E 46) The introduction of a new species into an area that has several different habitats and very rich resources, but no predators will likely lead to A) temporal isolation. B) limited speciation. C) adaptive radiation. D) extinctions. E) mechanical incompatibility. Answer: C 47) The organisms most likely to undergo sympatric speciation by polyploidy are A) protists. B) plants. C) birds. D) mammals. E) insects. Answer: B

48) The introduction of a few individuals into a new habitat that is unoccupied by other members of the species is a(n) A) limited speciation. B) founder event. C) temporal isolation. D) adaptive radiation. E) extinction. Answer: B 49) Hybridization of two species in which of the following cases could lead to the extinction of one of the original species? A) It may introduce deleterious genes from one species to another. B) An endangered species may further decline by producing less-fit hybrid offspring. C) Hybridization increases inbreeding, which decreases the average fitness of the species. D) The two species increase their population sizes, thus increasing the effects of genetic drift. E) The hybrid offspring may outcompete the parental species. Answer: B 50) In northern Minnesota, the lynx (Lynx canadensis) habitat overlaps the bobcat (Lynx rufus) habitat. The two can breed and produce healthy, fertile offspring, which could lead to A) extinction of one or both species. B) gametic incompatibility. C) hybrid infertility. D) hybrid inviability. E) geographicisolation. Answer: A 51) Which statement best describes how overspecialization can affect a species? A) New adaptations will never occur in a highly specialized species. B) Highly specialized adaptations are rare in species that occupy a very limited geographic range. C) Highly specialized adaptations enable a species to live anywhere on Earth. D) Highly specialized adaptations in a species increase the likelihood of extinction if the environment changes. E) If the habitat around a specialized species changes, the species always evolves new specialized adaptations. Answer: D 52) Which of the following is the most prevalent immediate cause of extinction? A) Specialization B) Disease C) Environmental change D) Predation E) Competition Answer: C

53) Which species is most likely to becomeextinct? A) Carp, found throughout Europe, the United States, and Canada B) The white tiger beetle, found throughout several mid-Atlantic U.S. states C) The northeastern pygmy shrew, found throughout New Jersey and Pennsylvania D) Kirtland's warbler, which breeds in only a small area of Michigan E) The jack-in-the-pulpit, found throughout the eastern United States and Canada Answer: D 54) Overspecialized adaptations A) are found only in species with very wide geographic ranges. B) enable a species to be more adaptable to environmental changes. C) promote survival in a wide range of habitats. D) are the result of naturalselection. E) enable a species to be more independent of other species. Answer: D 55) The most common cause of extinction is A) limited species range. B) habitat change. C) interactions with other species. D) asteroid impacts. E) overspecialization. Answer: B 56) What is the best explanation for the origin of the unique species recently found in the Annamite Mountains of Vietnam? A) Adaptive radiation B) Behavioral isolation C) Temporal isolation D) Allopatric speciation E) Sympatricspeciation Answer: D 57) Which species is least likely to becomeextinct? A) A fish species that feeds on only rare snails found in only one small river B) A fish species found in all five of the Great Lakes C) A fish species that has hybridized with another species to produce infertile offspring D) A mammal species that can live equally well on dry land and in fresh water E) A mammal species that feeds on a rare tropical orchid Answer: D 58) The immediate cause of most extinctions is A) wide distribution. B) genetic drift. C) hybridization. D) environmental change. E) overspecialization. Answer: D

59) Organisms from two separate species can look anatomically similar. A) True B) False Answer: A 60) Premating isolation mechanisms occur when two species have different and incompatible mating behaviors. A) True B) False Answer: A 61) Two species of plants that both use honeybees as pollinators but reproduce at different times of the year-one spring, the other midsummer-demonstrate geographicisolation. A) True B) False Answer: B 62) Hybrid inviability occurs when two species mate and produce fertile offspring. A) True B) False Answer: B 63) Polyploidy is an important mechanism of speciation in plants. A) True B) False Answer: A 64) Polyploidy is an important mechanism of speciation in animals. A) True B) False Answer: B SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 65) The biological species concept is based on the idea that individuals in one group are be unable to breed with individuals outside their group. This phenomenon is referred to as . Answer: reproductive isolation 66) One species of moss in upstate New York produces gametes in May, and another species of moss in the same region produces gametes in June. This is an example of a(n) isolating mechanism. Answer: temporal 67) Mechanisms that prevent mating between species are called

isolating mechanisms.

Answer: premating 68) Two organisms that live on different islands are experiencing

isolation.

Answer: geographic 69) When hybrid offspring are created between species but are unable to breed successfully, it is referred to as . Answer: hybrid infertility

70) Hybrid inviability is an example of a(n)

isolating mechanism.

Answer: postmating 71) In the late 1700s, two populations of minnows became isolated when an earthquake altered the path of a river. Now the populations can no longer successfully breed with each other even when they are both moved to the same pond. These organisms have undergone speciation. Answer: allopatric 72) For new species to develop, there must be

in the population.

Answer: geneticdivergence 73) A flower has four copies of each chromosome. This is an example of

Answer: polyploidy 74) Researchers believe that at least

% of the species that have lived on Earth have become extinct.

Answer: 99.9 75) Explain why naming and describing species based only on their appearance can be problematic. Answer: In some cases, individuals that look the same are actually different species. For example, the cordilleran flycatcher and the Pacific slope flycatcher look so similar that birdwatchers have difficulty telling them apart, but they are two different species that do not interbreed. In other cases, individuals that look very different are the same species. For example, the myrtle warbler and Audubon's warbler were once classified as separate species because they have different-colored throat feathers, but they are the same species. 76) What are the five premating isolating mechanisms that keep different species from successfully mating? Answer: The mechanisms are geographic isolation, ecological isolation, temporal isolation, behavioral isolation, and mechanical incompatibility. 77) A plant breeder can use plum pollen to hand-fertilize an apricot flower. The fruit contains fertile seed that grows into a hybrid called a plucot. However, in the natural environment, plums and apricots bloom several weeks apart. Why are plums and apricots considered separate species? Answer: Because the flowering occurs at two different times, the plants are temporally isolated. This premating isolation mechanism keeps them reproductively isolated in nature, a characteristic of separate species. 78) How do premating isolation mechanisms differ from postmating isolation mechanisms? Answer: Premating isolation mechanisms prevent mating from ever occurring, whereas postmating isolation mechanisms occur after mating and prevent the hybrid offspring from passing on its genes. 79) In what type of habitat, or under what types of environmental conditions, would you expect adaptive radiation to occur? Answer: Any habitat in which many different types of unexploited food resources and few or no competitors exist is ideal for adaptive radiation. This seems to be the case in Darwin's finches of the Galápagos Islands, the cichlids of Lake Malawi, and other classic examples of adaptive radiation. 80) Modern biologists have identified two main factors that drive speciation. What are these factors? Answer: The factors are isolation and genetic divergence.

81) Oceanic islands are not the only geographic habitats that can harbor isolated populations of individuals. What are some other examples of isolated "island" populations? Answer: Any habitat that contains a boundary that the organism cannot cross is considered an "island"-for example, a mountaintop, a small pond in the middle of an arid region, or even a living host (for a parasite). 82) From an evolutionary perspective, explain how three species of large, flightless birds (ostriches, rheas, and emus) came to occupy the widely separated landmasses of Africa, South America, and Australia. Answer: All of these birds evolved from a common "ratite" ancestor that lived on the supercontinent called Gondwana. In response to the extreme geographic isolation resulting from continental drift, allopatric speciation occurred and resulted in the three unique ratite species that are now found on the three different continents. 83) Einkorn (Triticum boeoticum) is an ancient grain with a diploid number of 14 (2n = 14). Durum (Triticum turgidum) appeared later. Durum grains are larger and the plant is hardier. It has twice the genetic material of Einkorn (2n = 28) but contains basically the same chromosomes. Can you propose a hypothesis on how durum evolved? Answer: Durum could possibly be a polyploidy of einkorn. Polyploid plants are common and may become new species. 84) What events can push a species to extinction? Answer: Possible causes of extinction include loss of a food source, hybridization, loss of habitat, and competition with another species for resources. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 85) Strong courtship displays like the one in the figure below can lead to

A) temporal isolation. B) mechanical incompatibility. C) behavioral isolation. D) hybrid infertility. E) geographicisolation. Answer: C

86) The series of events depicted in the figure demonstrates

A) hybrid infertility. B) allopatric speciation. C) mechanical incompatibility. D) temporal isolation. E) behavioralisolation. Answer: B SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 87) Store-bought hybrid tomatoes are very popular with consumers. Suppose you buy a tomato from the grocery store, collect seeds from it, and plant the seeds. If the seeds do not germinate, the seedlings fail to thrive, or the plants die quickly after sprouting, what reproductive isolating mechanism might be responsible? Answer: hybrid inviability

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 88) All members of the golden hamster species known today are descendants of a single litter collected in Syria in 1939. Its diploid chromosome number is 44. Two other species of hamster, each with a diploid number of 22, overlap geographically in Syria. The golden hamster is thought to be a new species from the mating of a male and female of the two other hamster species. What mechanism might explain this recent event of speciation? A) Disruptive selection B) Polyploidy C) Adaptive radiation D) Formation of a fertile hybrid and halving of the chromosome number of this hybrid E) Temporal isolation Answer: B 89) A European species of marsh grass called Spartina maritima has a diploid number (2n) of 60. A similar species native to North America, S. alterniflora, has 2n = 62. In 1835, the North American species was found growing near the European species in Southampton, England, after being accidentally imported. Occasional sterile hybrids were noted. In 1895 a new species, S. anglica, was first identified at Southampton and subsequently became common. The new species has been identified as a fertile hybrid of the original two species. What is the 2n chromosome number of the hybrids that formed from the original two species S. maritima and S. alterniflora? A) 153 B) 61 C) 60 D) 31 E) 122 Answer: B

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Louis Pasteur's experiment illustrated that A) only some organisms can form spontaneously in nutrient broth. B) microbes will grow spontaneously in a nutrient broth that has been sterilized and sealed. C) life began by chemical evolution. D) microbes will not grow in a nutrient broth that has been sterilized unless air is allowed to enter the vessel through an opening. E) some complex molecules associated with living organisms can be synthesized by heating and cooling a solution of simple molecules and providing an electric spark. Answer: D 2) The scientists usually given credit for disproving the theory of spontaneous generation of bacteria are A) Cech and Altman. B) Luis and Walter Alvarez. C) Oparin and Haldane. D) Miller and Urey. E) Tyndall and Pasteur. Answer: E 3) If you open a can of chicken noodle soup and immediately examine it microscopically, you will find no microorganisms. If you let the open can sit on the shelf for a few weeks and then examine it, you will find many microorganisms. The origin of these microorganisms is most likely A) spontaneous generation. B) improper sterilization of the soup prior to canning. C) endosymbiotic evolution. D) prebiotic evolution. E) airborne microorganisms. Answer: E 4) The theory that life began in the distant past from nonliving molecules that became able to reproduce themselves is called A) natural selection. B) prehistoric evolution. C) endosymbiont evolution. D) spontaneous evolution. E) prebiotic evolution. Answer: E 5) Theories on the atmosphere of early Earth indicate that it lacked A) CH4. B) NH3. C) H2. D) O2. E) H2O. Answer: D

6) What compounds were used in Miller and Urey's experiment to simulate the atmosphere of early Earth? A) Water, ammonia, hydrogen, and methane B) Ammonia, hydrogen, and carbon dioxide C) Water, oxygen, hydrogen, and methane D) Water, oxygen, ammonia, and methane E) Oxygen, ammonia, hydrogen, and methane Answer: A 7) Miller and Urey's experiments to simulate prebiotic evolution produced A) mitochondria and chloroplasts. B) large amounts of free oxygen. C) prokaryotic cells. D) a rich mixture of organicmolecules. E) protocells. Answer: D 8) Some RNA molecules have been discovered that can A) convert organic molecules to protocells. B) duplicate lipid molecules. C) act as enzymes. D) form primitive cells. E) degrade proteins. Answer: C 9) RNA molecules that function as enzymes A) developed from protein-based enzymes. B) are called ribozymes. C) duplicate lipid molecules. D) degrade proteins. E) form primitive cells. Answer: B 10) The outer boundaries of Miller and Urey's laboratory-created vesicles are most similar to A) complete cells. B) cell membranes. C) bacteria. D) RNA. E) amino acids. Answer: B 11) The scenario of prebiotic evolution leading to the origin of life on Earth is plausible because A) experiments suggest that all of the chemical components of living cells can be formed quickly from inorganic precursors. B) it has been observed to occur near thermal vents at the bottom of the ocean. C) it has been observed to occur on other planets. D) there was a vast period of time for simple chemicals to evolve into complex molecules found in cells that exist today. E) it has been observed under laboratory conditions. Answer: D

12) The experiments that demonstrated that meat does not spontaneously generate maggots were conducted by A) Louis Pasteur. B) Francisco Redi. C) Alexander Oparin. D) Sidney Altman. E) Harold Urey. Answer: B 13) The idea that river mud left in the sun will turn into frogs illustrates A) self-replication. B) how prokaryotes evolve. C) spontaneous generation. D) prebiotic evolution. E) the endosymbiont theory. Answer: C 14) Who disproved the "broth-to-microorganisms" hypothesis? A) Francisco Redi B) Sidney Altman C) Louis Pasteur D) Stanley Miller E) Alexander Oparin Answer: C 15) Which of the following scientists was part of a pair who first discovered that cellular reactions can be catalyzed by a ribozyme? A) Alexander Oparin B) John Tyndall C) Stanley Miller D) Francisco Redi E) Sidney Altman Answer: E 16) Who is credited with proposing that prebiotic chemical conditions could lead to the evolution of complex molecules and, eventually, to living organisms? A) Alexander Oparin and John Haldane B) Francisco Redi C) Stanley Miller D) Louis Pasteur E) Sidney Altman Answer: A 17) One theory holds that the first self-replicating molecules were A) DNA. B) amino acids. C) RNA. D) carbohydrates. E) lipids. Answer: C

18) The oldest fossil organisms presently known have been dated at approximately how many years old? A) 1.7 billion B) less than 1.7 billion C) 3.4 billion D) 4.5 billion E) more than 4.5 billion Answer: C 19) Which is the correct series of events in the evolution of life on Earth? A) Photosynthesis → O2 → aerobic metabolism B) Aerobic metabolism → photosynthesis → O2 C) O2 → aerobic metabolism → photosynthesis D) O2 → photosynthesis → aerobic metabolism Answer: A 20) Based on current knowledge about the conditions of early Earth, the first organisms were most likely A) anaerobic eukaryotes. B) multicellular eukaryotes. C) photosynthetic eukaryotes. D) photosynthetic prokaryotes. E) anaerobic prokaryotes. Answer: E 21) The oxygen that arose in early Earth's atmosphere was likely produced by organisms that were very similar to modern A) fungi. B) plants. C) protists. D) algae. E) cyanobacteria. Answer: E 22) The earliest fossil organisms resemble modern A) eukaryotes. B) prokaryotes. C) green algae. D) protists. E) protocells. Answer: B 23) The organisms originally responsible for putting oxygen in Earth's atmosphere lived around A) 6 billion years ago. B) 2.4 billion years ago. C) 3.5 million years ago. D) 1.5 million years ago. E) 3.5 billion years ago. Answer: B

24) The earliest photosynthetic organisms A) probably used water as a source of hydrogen. B) probably did not produce oxygen. C) possessed chloroplasts. D) probably used hydrogen sulfide as a source of hydrogen. E) date back to the time when life first emerged on Earth. Answer: D 25) If early Earth's atmosphere contained little or no O2, then where did most of the O2 in our modern atmosphere come from? A) Photosynthesis B) Respiration C) The splitting of water vapor by sunlight D) The breakdown of carbon dioxide E) The oxidation of metals Answer: A 26) Water-based photosynthesis converts carbon dioxide and which of the following to energy-containing molecules? A) Chlorophyll B) Hydrogen bromide C) Hydrogen sulfide D) Methane E) Water Answer: E 27) The endosymbiotic hypothesis accounts for the origin of which cell structure? A) Ribosome B) Plasma membrane C) Cell wall D) Chromosome E) Chloroplast Answer: E 28) An anaerobic prokaryote engulfs a prokaryote capable of using oxygen to produce energy. The anaerobe could now perform A) both photosynthesis and aerobic metabolism. B) only anaerobic metabolism. C) photosynthesis. D) aerobic metabolism. Answer: D 29) The hypothesis that certain eukaryotic cell structures may have evolved from a prokaryotic cell being engulfed by a eukaryotic cell is called the A) protocell hypothesis. B) spontaneous generation hypothesis. C) prebiotic evolution hypothesis. D) endosymbiont hypothesis. E) living intermediate hypothesis. Answer: D

30) To be classified as a eukaryote, an organism must have A) a cell wall. B) flagella. C) sexual reproduction. D) centrioles. E) internal membranes. Answer: E 31) Multicellularity enables organisms to overcome cellular limits and A) be photosynthetic. B) reproduce more efficiently. C) become big. D) become fast. E) undergo aerobic respiration. Answer: C 32) Probably the greatest advantage for the original multicellular organisms was their ability to A) avoid predation. B) increase their metabolism. C) use more oxygen. D) increase their food intake. E) photosynthesize. Answer: A 33) The first multicellular eukaryotic fossils were A) fungi. B) amphibians. C) algae. D) cyanobacteria. E) reptiles. Answer: C 34) The earliest multicellular animals in the fossil record are A) mammals. B) kelp. C) worms. D) sponges. E) trilobites. Answer: D 35) Modern invertebrates first appear in the fossil record during the A) Cambrian period. B) Silurian period. C) Precambrian era. D) Devonian period. E) cyanobacteria. Answer: C

36) Exoskeletons provided an evolutionary advantage to organisms by A) allowing exposure to oxygen. B) increasing their mobility and protecting them from predation. C) increasing their ability to find a mate and reproduce. D) increasing predation. E) allowing increased opportunities for symbiotic relationships. Answer: B 37) About 530 million years ago, what adaptation evolved to make fish the dominant predators of the sea? A) Internal skeleton B) Scales C) Sensory organs D) Jaws E) Fins Answer: A 38) The first multicellular terrestrial organisms were A) reptiles. B) fungi. C) plants. D) insects. E) amphibians. Answer: C 39) One advantage that enabled the seed plants to greatly surpass the ferns in colonizing the land was the evolution of A) photosynthesis. B) spores. C) sex without swimming sperm. D) a woody stem. E) a fibrous root system. Answer: C 40) To survive successfully on land, plants needed to develop A) the ability to use oxygen. B) methods to prevent water loss. C) photosynthesis. D) swimming sperm. E) internal skeletons. Answer: B 41) Flowering plants first rose to prominence in the A) Eocene epoch. B) Cretaceous period. C) Cambrian period. D) Paleozoic era. E) Precambrian era. Answer: B

42) Early land plants required adaptations that A) aided reproduction. B) decreased water loss. C) helped support theplant. D) all of the above. E) none of the above. Answer: D 43) The first land plants were restricted to moist, marshy environments because of A) reproductive cell requirements. B) the lack of a cuticle. C) the need for stem support. D) sensitivity to sunlight. E) the need for nutrients. Answer: A 44) The earliest group of land plants whose reproduction did not require water for swimming sperm were the A) club mosses. B) algae. C) ferns. D) conifers. E) lobefins. Answer: D 45) Ferns and club mosses had an advantage over earlier plants because they developed A) mitochondria. B) flowers. C) cones. D) photosynthesis. E) swimming sperm. Answer: E 46) Amphibians assumed to have evolvedfrom A) lobefin fish. B) arthropods. C) reptiles. D) segmented worm. E) mollusks. Answer: A 47) By examining fossil evidence, paleontologists believe that mammals evolved from ancestors of modern A) arthropods. B) reptiles. C) sharks. D) amphibians. E) lobefins. Answer: B

48) The exoskeleton of early marine arthropods can be considered a "pre-adaptation" for life on land because it A) absorbed light. B) reflected ultraviolet radiation. C) resisted water loss. D) protected against predators. Answer: C 49) Which group of vertebrates was the first to evolve a waterproof egg, which allowed the group to move away from water, deeper onto dryland? A) Primates B) Reptiles C) Lobefins D) Birds E) Mammals Answer: B 50) Birds and mammals have a more active lifestyle than reptiles due to A) a slower metabolism. B) internal fertilization. C) a high, constant body temperature and insulation over their body surface. D) internal fertilization and a high, constant body temperature. E) insulation over their body surface. Answer: C 51) The first terrestrial animals were probably A) amphibians. B) reptiles. C) dinosaurs. D) arthropods. E) mammals. Answer: D 52) The "pre-adaptations" of early arthropods that allowed them to evolve into terrestrial forms were A) eggs. B) lungs. C) kidneys. D) vertebral columns. E) exoskeletons. Answer: E 53) Arthropods were the first terrestrial animals because their exoskeletons allowed them to withstand A) starvation. B) ultraviolet radiation. C) the force of gravity. D) high oxygen concentrations. E) lower atmospheric pressure. Answer: C

54) The modern-day group of vertebrates that bridges the evolutionary gap between land-dwelling and water-dwelling organisms is A) amphibians. B) reptiles. C) whales and dolphins. D) fish. E) aquatic birds. Answer: A 55) Reptiles evolved scaly body coverings as a means for A) flight. B) heat production. C) insulation. D) courtship rituals. E) protection from drying out. Answer: E 56) The earliest group of land animals was the A) amphibians. B) protists. C) lungfish. D) lobefins. E) arthropods. Answer: E 57) The generally slow and steady succession of species on Earth has been interrupted by A) balanced polymorphism. B) episodes of mass extinction. C) genetic equilibrium. D) unusually high rates of platetectonics. E) extreme specialization of a few species. Answer: B 58) The largest mass extinction event of all time occurred at the end of the A) Permian period. B) Cambrian period. C) Cretaceous period. D) Pleistocene epoch. E) Mesozoic era. Answer: A 59) The "Southern Beech" tree is found in such diverse places as Australia, South Africa, and South America. People did not transplant it. How did it probably get to these widely separated locations? A) Seeds were carried by birds. B) These landmasses were once connected and later drifted apart. C) The simultaneous creation of the same species occurred in different geographic locations. D) Seeds were blown by the prevailing winds. E) Glaciers split what was once a continuous, huge population of beeches. Answer: B

60) Most scientists attribute the mass extinction of the dinosaurs to A) sunspots. B) meteorite impact. C) sea-level change. D) gradual climate change. E) predation by mammals. Answer: B 61) If the Cretaceous mass extinction had not occurred, which group of animals would probably include the largest land animals today? A) Bony fish B) Reptiles C) Insects D) Amphibians E) Birds Answer: B 62) The human species first appeared in the A) Tertiary period. B) Quaternary period. C) Cretaceous period. D) Permian period. E) Jurassic period. Answer: B 63) In addition to Homo, another genus within the hominins is A) Australopithecus. B) Lemur. C) Cro-Magnon. D) Tarsius. E) Habilis. Answer: A 64) Which of these characteristics separates primates from other mammals? A) Placental young B) Tree-dwelling C) Mammary glands D) Parental care of young E) Precision grip Answer: E 65) An adaptation that is closely associated with hominin evolution is A) grasping hands. B) a backbone. C) lungs. D) hair. E) omnivory. Answer: A

66) Current research indicates that hominins originally evolved in which continent? A) Africa B) Australia C) Asia D) North America E) Europe Answer: A 67) What is the significance of upright walking? A) It provides good posture. B) It facilitates digestion. C) It frees the hands for gathering and carrying food. D) It facilitates circulation. E) It facilitates social interactions. Answer: C 68) Which characteristic sets hominins apart from other primates? A) A four-chambered heart B) Binocular vision C) Bipedal locomotion D) Facial hair E) Grasping hands Answer: C 69) Which of the following species do paleoanthropologists believe may be the most direct ancestor to Homo sapiens? A) Homo ergaster B) Homo erectus C) Homo heidelbergensis D) Homo neanderthalensis E) Homo habilis Answer: C 70) Homo heidelbergensis is believed to be the ancestor species of A) Homo ergaster. B) Homo sapiens. C) Homo neanderthalensis and Homo sapiens. D) Homo ergaster and Homo sapiens. E) Homo neanderthalensis. Answer: C 71) The first hominin species associated with the use of tools was A) Homo habilis. B) Homo sapiens. C) Australopithecus afarensis. D) Australopithecus robustus. E) Homo erectus. Answer: A

72) The scientific name for Neanderthalsis A) Homo habilis. B) Homo sapiens. C) Homo erectus. D) Homo neanderthalensis. E) Australopithecus robustus. Answer: D 73) All surviving hominins belong to the species A) Homo habilis. B) Homo erectus. C) Australopithecus robustus. D) Homo robustus. E) Homo sapiens. Answer: E 74) What species of hominin created the cave paintings at Lascaux, France? A) Homo habilis B) Australopithecus afarensis C) Homo sapiens D) Homo erectus E) Australopithecus robustus Answer: C 75) Current theories hold that hominin species migrated out of Africa A) multiple times throughout history. B) once, nearly 800,000 years ago. C) once, about 150,000 years ago. D) once, 10 million years ago. E) once, nearly 2 million years ago. Answer: A 76) It has been proposed that large brains evolved in Homo species because A) natural selection favored large-brained individuals because they were better in social interactions. B) large brains allowed better visual acuity, which was favored by natural selection. C) genetic drift increased the frequency of large-brained alleles. D) large-brained individuals were better able to outwit and escape predators. E) evolution of a large brain was a consequence of evolution of overall larger body size. Answer: A 77) Which of the following processes involves behaviors that are acquired by learning and can be modified and passed on from one generation to the next? A) Environmental selection B) Natural selection C) Pre-adaptation D) Prebiotic evolution E) Cultural evolution Answer: E

78) A major human cultural innovation that happened about 10,000 years ago was the A) development of domesticated crops andlivestock. B) development of self-expression in artforms. C) development of language. D) ability to think in abstractterms. E) use of tools. Answer: A 79) The hobbit-sized hominin whose fossilized remains were recently discovered on a remote oceanic island belonged to the species A) Homo erectus. B) Homo neanderthalensis. C) Homo floresiensis. D) Homo sapiens. E) Homo habilis. Answer: C 80) Which era saw the rise of seeds and pollen in plants? A) Cenozoic B) Paleozoic C) Cretaceous D) Precambrian E) Mesozoic Answer: B 81) Continental drift is caused by A) ocean currents. B) plate tectonics. C) earthquakes. D) tidal forces. E) long-term weathering. Answer: B 82) Living organisms can spontaneously generate from nonliving matter. A) True B) False Answer: B 83) Miller and Urey's experiments attempting to re-create the prebiotic environment produced a rich mixture of complex organic chemicals from simplechemicals. A) True B) False Answer: A 84) Miller and Urey's experiments attempting to re-create the prebiotic environment produced prokaryotic cells. A) True B) False Answer: B

85) Some of the organic molecules on early Earth came from outer space. A) True B) False Answer: A 86) Some scientists theorize that early life was RNA-based. A) True B) False Answer: A 87) RNA can act like an enzyme. A) True B) False Answer: A 88) The earliest life-forms were photosyntheticeukaryotes. A) True B) False Answer: B 89) Organisms that have complex internal membranes are prokaryotic. A) True B) False Answer: B 90) Mitochondria contain their own DNA, separate from that of the rest of the cell. A) True B) False Answer: A 91) Cell size is limited by the ability of oxygen, nutrients, and wastes to diffuse through the cell membrane. A) True B) False Answer: A 92) All the life-forms found in the Silurian fossil record are still alive today. A) True B) False Answer: B 93) Pollen likely evolved in response to plants moving to drier land. A) True B) False Answer: A 94) Eggs and scales are features that enabled reptiles to dominate land during the Permian period. A) True B) False Answer: A

95) The extinction of the dinosaurs is thought to be due to a massive meteorite impact. A) True B) False Answer: A 96) Climate change has been linked to mass extinctions. A) True B) False Answer: A SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 97) Oxygen has a negative influence on the formation of complex organic molecules because it and changes their structure.

with them

Answer: reacts 98) The first self-replicating molecule was probably

Answer: RNA 99) Laboratory research has shown that if a solution containing lipids and proteins is agitated for a long time, then hollow structures called vesicles are produced that resemble . Answer: cells 100)

may have evolved from aerobic bacteria that were engulfed by predatory prokaryotic cells. Answer: Mitochondria

101)

may have evolved from photosynthetic cyanobacteria that were engulfed by predatory prokaryotic cells. Answer: Chloroplasts

102) Prokaryotic cells evolved about

years ago.

Answer: 3.5 billion 103) The fossil record indicates that about 600 million years ago, a wide variety of the oceans.

animals had evolved in

Answer: invertebrate 104) Pollen eliminated the need for

in plant reproduction.

Answer: water 105) The first animals to move onto land were

Answer: arthropods 106) Arthropods were able to move onto land because their

prevented dehydration and provided support.

Answer: exoskeleton 107) The fossil evidence indicates that amphibians evolved from Answer: fish

108) Lobefins are thought to have evolved into

Answer: amphibians 109) Prior to continental drift, North America and Eurasia formed a supercontinent called

Answer: Laurasia 110) The earliest upright

were in a group called australopithecines.

Answer: hominins 111) The oldest fossils of anatomically modern

are 160,000 years old.

Answer: Homosapiens 112) Humans are in the mammal group known as

Answer: primates 113) The first terrestrial plants were descendants of

Answer: algae 114) Fossils are aged by a process that examines the

of known radioactive elements.

Answer: ratio 115) Experiments that attempt to simulate conditions on early Earth have produced results that hint at the possible origins of life. What have the experiments produced? Answer: The early experiments have produced organic molecules, such as small amino acids and nucleotides that are now produced by living organisms, from inorganic molecules. 116) Why is RNA considered by many scientists to have been the basis for early forms of life? Answer: RNA is capable of both information storage (like DNA) and catalytic activity (like enzymes). RNA can also make exact copies of itself. The abilities to reproduce and to enzymatically catalyze reactions are important characteristics of cells. A primitive RNA-based biochemistry might have functioned much like today's "DNA → RNA → protein" system. 117) Explain why an organism that carries on aerobic metabolism has an advantage over an organism that uses anaerobic metabolism. Answer: Aerobic metabolism results in much greater amounts of usable energy from the same amount of food. It also provides a mechanism for protecting cells from the destructive effects of oxygen by using it for metabolism. 118) Describe how the mitochondrion evolved as an organelle, using the endosymbiont hypothesis. Answer: The mitochondrion probably began as an aerobic bacterium that was engulfed, but not digested, by another prokaryotic cell. The two cells began a symbiotic relationship that persisted, with the host cell providing protection and nutrients to the aerobic bacterium, which in turn provided adenosine triphosphate (ATP) or similar molecules to its host. 119) What adaptations did ancient algae have to make as they washed ashore and evolved into land plants? Answer: Ancient algae evolved waterproof coatings to prevent drying out, vascular tissue to move water from roots to leaves, thick cell walls to stand erect, gametes produced within structures to prevent drying out, and pollen to eliminate the need for water-based sperm transport.

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

120) Based on the graph, if 35% of the original 40K remains in a sample of basalt, what is the approximate age of the rock? A) 1 billion years old B) 2 billion years old C) 3 billion years old D) 4 billion years old E) 5 billion years old Answer: B 121) Based on the graph, if 60% of the original 40K remains in a sample of basalt, what is the approximate age of the rock? A) 1 billion years old B) 2 billion years old C) 3 billion years old D) 4 billion years old E) 5 billion years old Answer: A

122) The figure illustrates

A) Operin and Haldane's theory on the formation of living organisms. B) spontaneous generation. C) the development of prokaryotes from eukaryotic organisms. D) the formation of eukaryotes according to the endosymbiont theory. E) prebioticconditions. Answer: D

123) According the pictured phylogenetic tree, the common ancestor for all Homo species is

A) Homo ergaster. B) Homo habilis. C) Australopthecus afarensis. D) Homo erectus. E) Paranthropus boisei. Answer: C 124) While exploring a sulfur spring, a scientist finds a new organism. It is single-celled, lacks a cell wall, has a few internal membranes, and appears to have set up a symbiotic relationship with a species of free-living purple sulfur bacteria that are common in the spring. There are no other organisms within it. This new organism would be considered a(n) A) eukaryote. B) living intermediate. C) aerobe. D) prokaryote. Answer: B

125) Scientists find several sets of fossil remains in a cave. The skeletons appear have been buried with stone tools and carved jewelry of ivory and bone. The artifacts are dated to 90,000 years old. The skeletons are anatomically similar to modern humans. Based on this information, the skeletons most likely are all A) Cro-Magnons. B) Neanderthals. C) Australopithecus afarensis. D) Homo erectus. E) Homo floresiensis. Answer: A

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) What is the second of the two names in an organism's scientific name? A) Species B) Genus C) Kingdom D) Order E) Family Answer: A 2) A mountain lion, or puma, has the scientific name Felis concolor. The term Felis is the A) species. B) genus. C) kingdom. D) order. E) family. Answer: B 3) A house cat has the scientific name Felis catus. The term catus is the A) species. B) genus. C) kingdom. D) order. E) family. Answer: A 4) The Asian elephant has the scientific name Elephas maximus. The term Elephas is the A) species. B) genus. C) kingdom. D) order. E) family. Answer: B 5) What is the main reason scientists use Latin scientific names? A) All scientists speak Latin. B) Latin names are recognized worldwide, overcoming language barriers. C) Scientific publications are usually in Latin. D) Linnaeus was from Italy, so he spoke Latin. E) Common names don't soundprofessional. Answer: B 6) The science of reconstructing the evolutionary history of life is called A) biology. B) taxidermy. C) pre-adaptation. D) systematics. E) gradualism. Answer: D

7) Which of the following is the largest or most inclusive group? A) Order B) Genus C) Phylum D) Class E) Family Answer: C 8) Which of the following is the smallest or least inclusive group? A) Kingdom B) Domain C) Family D) Class E) Genus Answer: E 9) Which of the following is the smallest or least inclusive group? A) Class B) Genus C) Kingdom D) Order E) Species Answer: E 10) Which of the following is the correct way to write the scientific name of the wolf? A) Canis lupus B) canis lupus C) canis Lupus D) Canis Lupus E) Canis lupus Answer: E 11) Canis latrans, Canis lupus, and Canis familiaris are all members of the same A) genus. B) subspecies. C) race. D) species. E) family. Answer: A 12) If two organisms are members of the same phylum, then they must also be members of the same A) domain. B) genus. C) class. D) family. E) species. Answer: A

13) In the scientific name of humans, Homo sapiens, the term Homo is the A) class. B) family. C) order. D) genus. E) species. Answer: D 14) Which of the following groups contains the fewest number of species? A) Class B) Kingdom C) Phylum D) Order E) Domain Answer: D 15) The most powerful way to infer evolutionary relationships relies on which type of evidence? A) Comparison of DNA base sequences B) Comparative anatomy C) Behavioral similarities D) The ability to mate and produce fertile offspring Answer: A 16) A major difficulty facing systematists is A) sequencing DNA. B) placing specimens into the predefined taxonomic categories of species and genus. C) distinguishing similar features due to common ancestry from those due to convergent evolution. D) distinguishing anatomy from physiology in plant evolution. E) understanding the sequence of cell divisions in the early embryology of plants and animals. Answer: C 17) Historically, in the field of taxonomy, what characteristic was most commonly used for determining species relationships? A) Anatomical similarity B) DNA sequence similarity C) Geographic proximity D) Capability of interbreeding E) Chromosomal similarity Answer: A 18) Comparing the chromosomes of chimpanzees and humans has revealed that the two species A) are only distantly related. B) should not be classified in the same family. C) should be classified in the same species. D) are closely related. E) should be classified in the same genus. Answer: D

19) DNA analysis reveals that two species of birds appear to have evolved from a common ancestor. These two species belong to the same A) nest group. B) gene pool. C) species. D) clade. E) breeding group. Answer: D 20) Who was the Swedish naturalist who established the modern system for classifying organisms? A) Aristotle B) Linnaeus C) Whittaker D) Woese E) Darwin Answer: B 21) Which biologist first proposed that all organisms share a common ancestry? A) Aristotle B) Linnaeus C) Whittaker D) Woese E) Darwin Answer: E 22) Who introduced the "two-part" system (genus and species) that biologists use to name organisms? A) Aristotle B) Linnaeus C) Whittaker D) Woese E) Darwin Answer: B 23) Modern systematics constructs clades and evolutionary relationships on the basis of A) genetic similarities. B) fossils. C) mating behaviors. D) anatomical similarities. E) whether or not an organism reproducessexually. Answer: A 24) Before 1970, what was the basis for the biological classification system? A) Five kingdoms: Monera, Protista, Fungi, Animalia, and Plantae B) Two kingdoms: Animalia and Plantae C) Two kingdoms: Bacteria and Eukarya D) Two kingdoms: Monera and Animalia E) Three kingdoms: Bacteria, Animalia, and Plantae Answer: B

25) Which group contains mostly unicellular, eukaryotic organisms? A) Fungi B) Bacteria C) Animalia D) Protists E) Plantae Answer: D 26) An organism with a nucleus would be placed in which domain? A) Bacteria B) Archaea C) Eukarya D) Animalia E) Fungi Answer: C 27) A modern system of classification gives the category name domainto A) Fungi. B) Eukarya. C) Prokaryota. D) Hominidae. E) insects. Answer: B 28) Which of the following is prokaryotic? A) humans B) Plantae C) Archaea D) Fungi E) Animalia Answer: C 29) Which of the following is a prokaryote? A) Troglodytes gorilla B) Blechnum nudum C) Homo sapiens D) Vibrio cholerae E) Porifera Answer: D 30) Which of the following groups is composed of eukaryotic organisms? A) Archaea B) Fungi C) Monera D) Bacteria Answer: B

31) Which of the following groups is composed of eukaryotic organisms? A) Monera B) Bacteria C) Protists D) Archaea Answer: C 32) Based on evolutionary lineage, fungi and animals belong to the same A) clade. B) order. C) genus. D) family. E) species. Answer: A 33) Why do some biologists NOT consider reptiles to be a monophyletic group? A) Reptiles evolved independently at several different times in the past and from several different ancestral species. B) Reptiles, birds, amphibians, and fish appeared in the fossil record at approximately the same time. C) The ancestors of reptiles are the class Amphibia. D) All reptiles do not reproducesexually. E) Birds are the direct descendants of some reptiles. Answer: E 34) Which of the following is NOT a monophyletic group? A) The kingdom Animalia, which includes all animals B) The family Semionotidae, which includes fish that may not share a common ancestor C) Turtles and lizards D) The class Mammalia, which includes all mammals E) You, your parents, and your siblings Answer: B 35) Genetics studies of human populations have revealed that A) Homosapiens probably did not evolve from primates. B) humans have very little genetic variation compared to other mammals. C) all humans are virtually identical. D) human populations vary tremendously at the level of DNA sequences. E) it is nearly impossible to determine the relatedness of human populations. Answer: B 36) The greatest genetic diversity among humans is found between some A) Australian B) African C) European D) North American E) Asian Answer: B

populations.

37) What should biologists do when two similar organisms that were originally thought to be separate species are found to interbreed freely and produce normal offspring whenever they live in the same habitat? A) Separate the two groups until they become dissimilar enough to prevent interbreeding. B) Consider both types to be a single species. C) Develop a new name for the hybrids. D) Retain the two species' names if the organisms have very different appearances. Answer: B 38) If genetic studies reveal that a population has genetic sequences in common with two closely related species but has no unique sequences of its own, then A) it should be assigned separate species status. B) it should be considered a hybrid of the two species. C) all three should be assigned to the same species. D) all three should be considered subspecies within the same species. E) it should be assigned to the species with which it shares more sequences. Answer: B 39) Systematics reassigns phylogenetic placement based on A) reproduction. B) behaviors. C) new information about genetic relationships. D) physical features. E) seed formation. Answer: C 40) Evolutionary relationships among organisms are most likely to be revised at the A) domain B) species C) genus D) kingdom E) order Answer: B 41) The total number of named species is about A) 1,600. B) 160. C) 1.6 million. D) 160,000. E) 1.6 billion. Answer: C 42) The number and variety of species in an area is the A) domain. B) clade. C) biodiversity. D) taxonomy. E) synapomorphy. Answer: C

level.

43) The science of reconstructing an organism's evolutionary history is called systematics. A) True B) False Answer: B 44) Each class can be split into several kingdoms. A) True B) False Answer: B 45) All organisms that are derived from a single common ancestor make up a clade. A) True B) False Answer: A 46) Systematics holds that the more similar the DNA of two organisms, the more closely related they are. A) True B) False Answer: A 47) Scientists currently identify three domains: plants, animals, and bacteria. A) True B) False Answer: B 48) Systematists use synapomorphies to build phylogenetic trees. A) True B) False Answer: A 49) Monophyletic groups contain all the species that evolved from a common ancestor. A) True B) False Answer: A 50) Once an organism is placed in a specific species, the designation cannot be changed. A) True B) False Answer: B 51) A phylogenetic species is defined as the smallest diagnosable group that contains all the descendants of a single common ancestor. A) True B) False Answer: A 52) Current research indicates that the temperate forest has the greatest biodiversity. A) True B) False Answer: B

53) Research indicates that HIV developed from a bird virus. A) True B) False Answer: B 54) The virus most closely related to HIV infects monkeys. A) True B) False Answer: A SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 55) The second of the two names in an organism's scientific name is the

Answer: species 56) Historically, most classification has been based on

similarity.

Answer: anatomical 57)

evolution results in similar anatomical features between unrelated organisms that may be misleading in determining species relationships. Answer: Convergent

58)

is a term that refers to the "evolutionary history" of an organism. Answer: Phylogeny

59) Based on taxonomic ranks, each order is divided into

Answer: families 60) Modern systematics isbased on

similarities.

Answer: molecular 61) HIV appears to have developed from a(n)

Answer: monkeyvirus 62) Based on current hypotheses, the prokaryotic group that gave rise to eukaryotes is the

Answer: Archaea 63) Fungi and animals belong tothe domain

Answer: Eukarya 64) Sponges and worms belong to the domain

Answer: Eukarya 65) Ferns and flowering plants belong to the clade

Answer: Plantae 66) Two butterflies have identical wing patterns, but in one the pigment is blue and in the other the pigment is yellow. The original ancestor had green wing pigments. The wing pigment is an example of a(n) . Answer: synapomorphy

67) Eukaryotes that are not plants, animals, or fungi are classified as

Answer: protists 68)

groups are groups in which all members are descendants of a common ancestor. Answer: Monophyletic

69)

groups contain only some of the descendants of a common ancestor. Answer: Paraphyletic

70) Dogs, wolves, foxes, and coyotes are genetically similar and form a group called a

Answer: clade 71) Organisms that reproduce

do not meet the standard criterion of a species.

Answer: asexually 72) The smallest diagnosable group that contains all the descendants of a single common ancestor is a(n)

Answer: phylogeneticspecies 73) List the following taxonomic categories from the most specific to the most general: genus, domain, family, phylum, order. Answer: genus → family → order → phylum → domain 74) How did Darwin's evolutionary theory change the significance of the taxonomic categories of organisms? Answer: Taxonomic categories are now considered to reflect the evolutionary relationships among organisms. 75) Briefly explain why the adoption of a standard, two-part scientific naming system is helpful to biologists. Answer: "Common names" can create confusion because the same common name may be used for different species and different common names may be used for the same species. In contrast, standard scientific names can be recognized by biologists worldwide and help them avoid confusion when discussing organisms. In addition, the two-part name makes it easy for biologists to discern whether two species are closely related (that is, whether they are in the same genus). 76) Why can organisms that look physically similar belong to different clades? Answer: A clade is based on genetic similarity. Convergent evolution may result in organisms with similar physical appearances, but if the organisms are from different evolutionary lineages, they cannot be in the same clade. 77) Explain how systematics and Linnaean taxonomy differ. Answer: Linnaean taxonomy is based on physical characteristics, whereas systematics looks at evolutionary relationships. 78) How can DNA tell you how closely related two organisms are? Answer: The more closely related two organisms are, the more similar their DNA sequences. 79) How do Archaea and Bacteriadiffer? Answer: They differ in the nucleotide sequences of RNA, which results in protein differences.

80) Why are Archaea and Bacteria, which are both prokaryotes, different domains? Answer: The two differ in the forms of proteins that are coded by different DNA sequences. Specifically, the ribosomes of the two groups are different. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

81) Based on the evolutionary tree shown here, which two organisms are most closely related? A) Chimps and bonobos B) Common gibbons and chimps C) Orangutans and common gibbons D) Humans and orangutans E) Humans and gorillas Answer: A 82) Based on the evolutionary tree, which organism's species split earliest from other members of the clade? A) Orangutans B) Gorillas C) Chimps D) Common gibbons E) Humans Answer: D

83) Based on the tree of life, which two groups have the closest ancestor in common? A) Animals and fungi B) Bacteria and animals C) Archaea and fungi D) Protists and fungi E) Plants and Archaea Answer: A 84) According to chemical and molecular evidence, members of the kingdom Fungi are most closely related to which of these groups in the tree of life? A) Protists B) Animals C) Plants D) Archaea E) Bacteria Answer: B

85) Based on the eukaryotic tree, gymnosperms are most closely related to A) zygomycota. B) angiosperms. C) porifera. D) chlorophyta. E) oomycota. Answer: B 86) Based on the eukaryotic tree, diatoms are most closely related to A) cnidaria. B) oomycota. C) phaeophyta. D) porifera. E) ciliates. Answer: C 87) Based on the eukaryotic tree, deuterostomes are most closely related to A) angiosperms. B) porifera. C) protostomes. D) diplomonads. E) pteridophyta. Answer: C

88) Based on the phylogeny figure, HIV-1 (strain 1) is most closely related to A) HIV-2 (strain 1). B) SIV-mandrill. C) HIV-2 (strain 2). D) SIV-chimpanzee (strain 1). E) SIV-sooty mangeby monkey. Answer: D 89) Based on the phylogeny figure, HIV-1 (strain 1) and HIV-2 (strain 2) A) both evolved into SIV-sooty mangeby monkey. B) both evolved from SIV-chimpanzee (strain2). C) evolved into HIV-2 (strain 1). D) became SIV-mandrill. E) share the least DNA in common. Answer: E 90) Suppose a population of a new plant is found on an island. DNA sequencing determines that this plant shares a limited number of genes with plants on the mainland. Within the species, there is great genetic variability. This would suggest that A) this plant species has been isolated on the island for a long period of time. B) this new species is more closely related to animals. C) this plant species is very closely related to plants on the mainland. D) DNA sequencing is unreliable for determining genetic linkages. Answer: A

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Bacterial cellwalls contain A) starch B) peptidoglycan C) pectin D) cellulose E) chitin

, which makes them different from other organisms.

Answer: B 2) Peptidoglycan is found in the cell walls of A) fungi. B) bacteria. C) plants. D) viruses. E) archaea. Answer: B 3) The classification of bacteria has historically been based on A) nutrient requirements and pigments. B) the appearance of colonies and rate of growth. C) pigments and presence of flagella. D) the means of locomotion and thickness of cell wall. E) microbial nutrition, physical appearance, and how they move. Answer: E 4) What differentiates gram-positive bacteria from gram-negative bacteria? A) The way the cell wall stains B) The use of oxygen C) The means of locomotion D) The appearance of colonies E) Nutrient requirements Answer: A 5) In which of these environments would you normally find prokaryotes? A) A single drop of seawater B) Human skin C) A spoonful of soil D) An animal's intestinal tract E) All of the above Answer: E 6) Which of the following is within the size range of a typical prokaryote? A) A cell 25 micrometers indiameter B) A cell 700 micrometers long C) A cell the size of the period at the end of a sentence D) A cell 100 micrometers indiameter E) A cell 2 micrometers in diameter Answer: E

7) Mobile prokaryotes can move around with the help of A) sex pili. B) flagella. C) peptidoglycan. D) endospores. E) plasmids. Answer: B 8) How do the flagella of bacteria differ from the flagella of archaea? A) Archaeal flagella are thinner than bacterial flagella. B) Bacterial flagella occur at only one end of the cell. C) Bacterial flagella cannot rotate. D) The flagella of archaea are scattered over the cell surface. E) Bacterial flagella are used for reproduction. Answer: A 9) Bacterial endospores are used for A) forming biofilms. B) keeping the bacteria alive under harsh conditions. C) bioremediation. D) attracting viruses. E) bacterial reproduction. Answer: B 10) What do the sticky layers of protective slime produced by some bacteria enable them to do? A) Sexually reproduce B) Move from one location toanother C) Acquire resistance to antibiotics D) Stick together and form biofilms E) Survive extreme conditions for long periods of time Answer: D 11) Dental plaque is an example of A) beneficial bacteria. B) an endospore. C) a cell membrane. D) bacterial flagella. E) abiofilm. Answer: E 12) Which structure enables a bacterium to survive and infect a host even after a long period of desiccation? A) Capsule B) Endospore C) Pili D) Protein coat E) Slime layer Answer: B

13) The oldest endospores to be revived and cultured to produce live bacteria are A) 250,000 years old. B) 2,500 years old. C) 25,000 years old. D) 250 million years old. E) 250 years old. Answer: D 14) Sex pili are prokaryotic structures that are used A) during binary fission. B) during conjugation. C) for movement. D) for gathering prey. E) for adhering to surfaces. Answer: B 15) Binary fission is the method by which bacteria A) reproduce. B) survive extreme conditions for long periods of time. C) metabolize without oxygen. D) acquire genetic variation. E) move to new locations. Answer: A 16) Through which process are bacteria able to exchange genetic material? A) Anaerobic respiration B) Sexual reproduction C) Photosynthesis D) Endospore formation E) Conjugation Answer: E 17) Some bacteria use H2S instead of H2O in photosynthesis, and they release A) sulfur. B) carbon monoxide. C) oxygen. D) ethanol. E) acetic acid. Answer: A 18) Cyanobacteria obtain energy from A) parasitizing viruses. B) digesting plants. C) digesting cyanide. D) sunlight. E) digesting benzene. Answer: D

19) In bacteria, the small, circular pieces of DNA that are located outside the chromosome are called A) sex pili. B) endospores. C) bacteriophages. D) plasmids. E) flagella. Answer: D 20) Mutations that improve the survival and reproduction of organisms, and thus contribute to the evolution of species, arise rapidly in prokaryotes due to their A) anaerobic metabolism. B) rapid rate of cell division. C) cell wall composition. D) sexual reproduction. E) absence ofa nucleus. Answer: B 21) Intestinal bacteria are necessary for plant-eating animals to digest A) lipids. B) proteins. C) carbon dioxide. D) nitrogen. E) cellulose. Answer: E 22) Legumes obtain a useful form of A) carbon B) hydrogen C) nitrogen D) oxygen E) sulfur

from bacteria that live in root nodules.

Answer: C 23) Which of the following plants contains nitrogen-fixing bacteria in its root nodules? A) Potatoes B) Oranges C) Tomatoes D) Corn E) Soybeans Answer: E 24) Through which process do bacteria recycle nutrients in the environment? A) Decomposition B) Conjugation C) Endospore formation D) Photosynthesis E) Binary fission Answer: A

25) Oil spills are sprayed with bacterial cultures in order to A) kill the bacteria. B) prevent the oil from sticking to wildlife. C) make the oil easier to wash away. D) detoxify the oil. E) break down the oil. Answer: E 26) The use of bacteria to break down pollutants is referred to as A) bioremediation. B) biosynthesis. C) nitrogen-fixation. D) biofixation. E) binary fission. Answer: A 27) The causative agents of bubonic plague, which killed 100 million people during the 14th century, were A) fish. B) rats. C) fleas. D) bacteria. E) viruses. Answer: D 28) Lyme disease is caused by A) Borellia burgdorferi. B) nitrogen-fixing bacteria. C) contaminated water. D) Clostridium botulinum. E) rats. Answer: A 29) Disease-causing bacteria are called A) protozoa. B) pathogens. C) viroids. D) cyanobacteria. E) archaea. Answer: B 30)

are used in the production of foods such as yogurt, cheese, and sauerkraut. A) Bacteria B) Eukaryotes C) Viroids D) Protists E) Viruses Answer: A

31) Which of the following is the dreaded "black death" bacterium? A) Escherichia coli B) Streptococcus C) Yersinia pestis D) Clostridium E) Borrelia burgdorferi Answer: C 32) Which of the following is a normal inhabitant of a cow's digestive tract that can cause harm to people when it contaminates ground beef? A) Streptococcus pneumoniae B) Clostridium tetani C) Escherichia coli D) Yersinia pestis E) Borrelia burgdorferi Answer: C 33) The cause of tetanus is A) Clostridium tetani. B) Borrelia burgdorferi. C) Streptococcus pneumoniae. D) Campylobacter. E) Escherichia coli. Answer: A 34) The corkscrew-shaped bacterium system issues. A) Escherichia coli B) Borrelia burgdorferi C) Yersinia pestis D) Clostridium botulium E) Clostridium tetani

is vectored by ticks into humans and eventually may cause nervous

Answer: B 35) Which of the following causes AIDS (acquired immune deficiency syndrome)? A) A virus B) A bacterium C) A prion D) An archaea E) A viroid Answer: A 36) Viruses that attack prokaryotes arecalled A) prions. B) human pathogens. C) bacteriophages. D) host cells. E) viroids. Answer: C

37) Short, circular strands of RNA that can cause plant diseases are called A) prions. B) archaea. C) viruses. D) bacteria. E) viroids. Answer: E 38) Which of the following has no organelles, ribosomes, or cytoplasm? A) A bacterium B) A cyanobacterium C) An alga D) A virus E) A plant Answer: D 39) A virus basically consists of A) proteins and a cell membrane. B) RNA or DNA and a protein coat. C) RNA or DNA and amembrane. D) enzymes and a protein coat. E) RNA or DNA and enzymes. Answer: B 40) Which of the following consists of a protein coat surrounding a molecule of genetic material? A) Archaea B) Bacteria C) Viruses D) Protists E) Prions Answer: C 41) Which of the following is NOT alive? A) Virus B) Plant C) Bacterium D) Cyanobacterium E) Protist Answer: A 42) Which virus attacks white blood cells? A) HIV B) Herpes C) Influenza D) Smallpox E) Rabies Answer: A

43) Antibiotics can be effective only against a A) viroid. B) bacterium. C) prion. D) virus. Answer: B 44) For which of the following diseases or conditions should antibiotics be used? A) Mad cow disease B) A common cold C) AIDS (to combat HIV) D) Lyme disease E) Smallpox Answer: D 45) Viroids A) are infectious chains of aminoacids. B) are infectious pieces of DNA enclosed in a protein coat. C) attack bacteria. D) are infectious pieces of RNA. E) have a plasma membrane. Answer: D 46) Prions are A) also known as viroids. B) improperly folded proteins. C) viral protein coats. D) bacterial proteins. E) sexually transmitted bacteria. Answer: B 47) The common cold is caused by a A) bacterium. B) prion. C) virus. D) viroid. E) fungus. Answer: C 48) Bovine spongiform encephalopathy, or mad cow disease, is caused by a A) bacterium. B) prion. C) virus. D) viroid. E) fungus. Answer: B

49) Creutzfeldt-Jakob disease is caused bya A) bacterium. B) prion. C) virus. D) viroid. E) fungus. Answer: B 50) AIDS is caused by a A) bacterium. B) prion. C) virus. D) viroid. E) fungus. Answer: C 51) Avocado sunblotch is caused by a A) bacterium. B) prion. C) virus. D) viroid. E) fungus. Answer: D 52) Herpes is caused by a A) bacterium. B) prion. C) virus. D) viroid. E) fungus. Answer: C 53) Rabies is caused by a A) bacterium. B) prion. C) virus. D) viroid. E) fungus. Answer: C 54) Which of the following causes infectious sores on the mucous membranes of the mouth that occur during times of stress? A) Escherichia B) Listeria C) Bacillus anthracis D) Herpes virus E) Prions Answer: D

55) Which is the correct sequence of viral replication? A) Penetration → transcription → assembly → genetic material replication → protein synthesis B) Penetration → genetic material replication → transcription → assembly → protein synthesis C) Transcription → penetration → genetic material replication → assembly → protein synthesis D) Penetration → genetic material replication → transcription → protein synthesis → assembly E) Genetic material replication → penetration → transcription → assembly → protein synthesis Answer: D 56) Bacteria lack membrane-bound organelles. A) True B) False Answer: A 57) Bacteria are multicellular microbes. A) True B) False Answer: B 58) Bacteria are able to increase their genetic variability by reproducing sexually. A) True B) False Answer: B 59) Bacterial endospores are easily damaged by heat and drying. A) True B) False Answer: B 60) Biofilms are the immune system's way to keep pathogens from colonizing a host. A) True B) False Answer: B 61) Some archaea can live in boiling water. A) True B) False Answer: A 62) Anaerobic bacteria require high levels of oxygen to survive. A) True B) False Answer: B 63) Nitrogen-fixing bacteria remove nitrogen from plants and return it to the soil. A) True B) False Answer: B

64) Humans can eat live cultures of some bacteria without getting sick. A) True B) False Answer: A 65) Bioremediation is the process in which bacteria digest plants and release oily toxins. A) True B) False Answer: B 66) Organisms that produce disease are pathogens. A) True B) False Answer: A 67) All bacteria are harmful to humans. A) True B) False Answer: B 68) Viruses contain both DNA and RNA. A) True B) False Answer: B 69) Prions are made up of only protein. A) True B) False Answer: A 70) Kuru is caused by one of the archaea. A) True B) False Answer: B 71) Because viruses have limited genetic material, their mutation rates are very low. A) True B) False Answer: B 72) Smallpox is caused by infected rats. A) True B) False Answer: B SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 73) The bacterial cell wall can contain

Answer: peptidoglycan

74) The classifications gram-positive and gram-negative are based on

of the bacterial cell wall.

Answer: staining 75) The largest prokaryote is

Answer: Thiomargarita 76) Many prokaryotes thrive in

environments, which lack oxygen.

Answer: anaerobic 77) Unlike aerobic prokaryotes, anaerobic prokaryotes can obtain energy when

is notavailable.

Answer: oxygen 78) Cyanobacteria are

prokaryotes.

Answer: photosynthetic 79) Cyanobacteria obtain energy through

Answer: photosynthesis 80) Lyme disease iscaused by

that are transmitted to humans by deerticks.

Answer: bacteria 81) Tetanus is caused by

bacteria that grow in deep puncture wounds.

Answer: anaerobic 82) A bacterium capable of causing disease in a host is a(n)

Answer: pathogen 83)

is the process by which bacteria return nutrients to the soil. Answer: Decomposition

84) A particle that lacks all organelles and must always reproduce as an intracellular parasite is a(n)

Answer: virus 85) How do members of Archaea differ from the Bacteria? Answer: Bacterial cell walls contain peptidoglycan; archaeal walls lack peptidoglycan. Other differences include different ribosomes, different cell membranes, and different mechanisms for protein synthesis. 86) Briefly explain how the classification of prokaryotes has changed in recent years due to new technological advances. Answer: Until recently, prokaryotes were classified on the basis of their appearance, staining properties, nutrient requirements, and means of locomotion. With new genetic techniques, modern microbiologists rely heavily on comparisons of DNA and RNA nucleotide sequences when classifying prokaryotic species. 87) How do bacteria transfer genetic material without reproducing? Answer: Bacteria can pass information on a plasmid via conjugation.

88) Why are bacteria able to evolve so quickly? Answer: Binary fission is a rapid process. Some bacteria have the ability to divide via binary fission every 20 minutes. This rapid rate of division allows for mutations to occur much more quickly than cells dividing more slowly. 89) In what ways are bacteria beneficial to humans? Answer: Bacteria make food and some vitamins for us, recycle nutrients in the environment, and can be used for bioremediation. 90) In their relationships with humans, are most species of bacteria beneficial, harmful, or no noticeable purpose? Answer: The vast majority of prokaryotic species are beneficial to humans. Only small numbers are pathogenic, but those species tend to get a lot of our attention! 91) Are viruses alive or not? Explain your reasoning. Answer: Viruses are simply genetic material (DNA or RNA) surrounded by a protein coat. They are able to make copies of themselves only with the help of a host cell. Viruses are not organized on a cellular level and have no metabolism, cytoplasm, or self-made membranes. They cannot synthesize organic molecules. Because they lack these and other characteristics of living organisms, they should not be considered alive. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 92) The bacterium in the figure contains a(n)

A) prion. B) biofilm. C) nucleus. D) endospore. E) virus. Answer: D

93) The nodules in the figureare

A) converting nitrogen gas to a form usable by plants. B) protecting the plant from viroids. C) carrying on photosynthesis. D) intended to hold pathogenic bacteria. E) intended to exchange genetic material between the plant and the bacteria. Answer: A 94) The organism in the figureparasitizes

A) bacteria. B) protists. C) animals. D) plants. E) fungi. Answer: A

95) While examining a hot spring, you find something you haven't seen before. It has a cell membrane, but the cell wall lacks peptidoglycan. It contains both DNA and RNA. The DNA is circular. It would be classified as a(n) A) prion. B) virus. C) fungus. D) archaea. E) bacterium. Answer: D 96) Assume a genetic analysis of a sick animal's DNA indicates that part of one chromosome does not belong to the animal. It is foreign DNA and is not similar to any of the animal's normal genes. It most likely comes from a(n) A) bacterial infection. B) prion infection. C) fungal infection. D) viral infection. E) archaeal infection. Answer: D 97) You discover a new particle. It has only RNA as a nucleic acid and lacks both a membrane and cytoplasm. This particle is a(n) A) virus. B) archaea. C) bacteria. D) fungus. E) prion. Answer: A

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Which one of the following groups is characterized as eukaryotic? A) Protists B) Bacteria C) Prions D) Viruses E) Cyanobacteria Answer: A 2) Which of the following best fits into the protist's group? A) Plants B) Fungi C) Animals D) Prokaryotes E) Any eukaryote that is not a plant, animal, or fungus Answer: E 3) A protist that lives inside a host organism and absorbs nutrients from that living host is A) photosynthetic. B) symbiotic. C) parasitic. D) a decomposer. E) predatory. Answer: C 4) Protists A) form a single clade. B) develop embryos during reproduction. C) carry out photosynthesis without chloroplasts. D) are prokaryotic. E) obtain nutrition through a variety of different methods. Answer: E 5) Protists that absorb nutrients from dead organic matter are called A) symbiotic. B) parasitic. C) decomposers. D) predatory. E) photosynthetic. Answer: C 6) Protist photosynthesis relies on A) pseudopods. B) chloroplasts. C) pseudoplasmodia. D) silica. E) eyespots. Answer: B

7) The first protist chloroplast was likely to have been a(n) A) virus. B) chemosynthetic bacterium. C) symbiotic green alga. D) photosynthetic bacterium. E) example of secondary endosymbiosis. Answer: D 8) Secondary endosymbiosis can occur when a A) nonphotosynthetic protist engulfs a photosynthetic bacterium. B) virus infects a photosynthetic prokaryote. C) green alga engulfs a photosyntheticbacterium. D) nonphotosynthetic protist engulfs a photosynthetic protist. E) protist evolves to become a prokaryote. Answer: D 9)

are photosynthetic protists. A) Prokaryotes B) Parasites C) Plants D) Fungi E) Algae Answer: E

10) The foundation of a marine food chain is A) fungi. B) plants. C) viruses. D) algae. E) Archaea. Answer: D 11) A flagellated protist lives inside the guts of termites and enables the termites to digest the cellulose in wood as a food source. This protist belongs to the A) ciliates. B) Archaea. C) apicomplexans. D) amoebas. E) parabasalids. Answer: E 12) Protists that have two nuclei are classified as A) ciliates. B) parabasalids. C) amoebas. D) diplomonads. E) apicomplexans. Answer: D

13) Protists that lack mitochondria are A) euglenozoans. B) apicomplexans. C) excavates. D) ciliates. E) amoebas. Answer: C 14) Which protist causes a sexually transmitted disease? A) Giardia B) Trichomonas C) Pfiesteria D) Trypanosoma E) Plasmodium Answer: B 15) Both Trichomonas and Giardia are parasitic protists in the group called A) alveolates. B) euglenids. C) slime molds. D) excavates. E) diatoms. Answer: D 16) Which cell structure is missing in Trichomonas and Giardia? A) Mitochondria B) Flagella C) Nuclei D) Cell membranes E) Cysts Answer: A 17) A parasitic protist that presents a major health problem to backpackers and hikers if they drink unfiltered stream or lake water is A) Giardia. B) Plasmodium. C) Trypanosoma. D) Pfiesteria. E) Didinium. Answer: A 18) Which group of protists includes photosynthetic, unicellular, freshwater organisms that possess eyespots? A) Alveolates B) Brown algae C) Apicomplexans D) Amoebas E) Euglenids Answer: E

19) Which group of protists includes photosynthetic, individual cells that lack a rigid cell wall and move via a flagellum? A) Slime molds B) Water molds C) Amoebas D) Euglenids E) Diatoms Answer: D 20) The eyespot of a Euglena cell enables it to A) photosynthesize. B) see images in black and white only. C) spot potential predators. D) see images in color. E) orient toward light. Answer: E 21) Which of the following is a characteristic of the organism that causes malaria? A) Viral B) Multicellular C) Photosynthetic D) Prokaryotic E) Unicellular Answer: E 22) Which protist causes African sleeping sickness? A) Plasmodium B) Didinium C) Giardia D) Pfiesteria E) Trypanosoma Answer: E 23) Which protist group includes the water molds, diatoms, and brown algae? A) Slime molds B) Excavates C) Diplomonads D) Stramenopiles E) Euglenids Answer: D 24) Which group has caused such agricultural problems as downy mildew, potato blight, and an avocado disease? A) Protozoa B) Oomycetes C) Slime molds D) Diatoms E) Cyanobacteria Answer: B

25) The oomycete that nearly destroyed the French wine industry in the late 1870s was A) red tide. B) acercozoan. C) a protozoan. D) a slime mold. E) a water mold. Answer: E 26) Which group comprises a significant portion of phytoplankton and therefore is important to marine food webs? A) Cyanobacteria B) Protozoa C) Slime molds D) Euglenids E) Diatoms Answer: E 27) Which group is characterized by gritty, glassy, protective shells? A) Dinoflagellates B) Water molds C) Diatoms D) Slime molds E) Brown algae Answer: C 28) Which unicellular protists have silica shells consisting of top and bottom halves that fit together like pillboxes? A) Diatoms B) Amoebas C) Apicomplexans D) Slime molds E) Euglenids Answer: A 29) Which organism caused the disease that destroyed potato crops and led to the Irish potato famine in the mid-1800s? A) Trypanosoma B) Alveolates C) Kinetoplastids D) Water mold E) Excavates Answer: D 30) Free-floating, photosynthetic, unicellular protists include A) amoebas. B) ciliates. C) cyanobacteria. D) brown algae. E) phytoplankton. Answer: E

31) Paralytic shellfish poisoning occurs when A) diatoms B) dinoflagellates C) excavates D) euglenids E) diplomonads

are eaten by humans or marine mammals.

Answer: B 32) Both cyanobacteria and phytoplankton are A) multicellular. B) heterotrophic. C) photosynthetic. D) eukaryotic. E) parasitic. Answer: C 33) Which organisms are responsible for the majority of photosynthesis? A) Cyanobacteria B) Phytoplankton C) Conifers D) Ferns E) Flowering plants Answer: B 34) Both Didinium and Paramecium are protists in the group called A) slime molds. B) rhizarians. C) ciliates. D) excavates. E) alveolates. Answer: C 35) Which group is commonly referred to as the "seaweeds"? A) Water molds B) Phytoplankton C) Ciliates D) Brown algae E) Cyanobacteria Answer: D 36) Which protist group includes organisms that can reach heights of hundreds of feet and grow more than half a foot per day? A) Cyanobacteria B) Water molds C) Brownalgae D) Slime molds E) Phytoplankton Answer: C

37) The giant kelp found along the Pacific coast is an example of A) phytoplankton. B) cyanobacteria. C) brown algae. D) water molds. E) slime molds. Answer: C 38) Which protist group includes the dinoflagellates, apicomplexans, and ciliates? A) Protozoa B) Diatoms C) Stramenopiles D) Euglenids E) Alveolates Answer: E 39) Which group of photosynthetic, mostly marine protists was named for the motion created by their two whip-like flagella? A) Euglenids B) Cercozoans C) Amoebas D) Dinoflagellates E) Apicomplexans Answer: D 40) When a red tide occurs, huge numbers of microscopic organisms are filtered out of coastal waters by oysters and clams. This sometimes causes the shellfish to become toxic to people who eat them. The organisms that create the red tide are classified as A) slime molds. B) euglenids. C) dinoflagellates. D) diatoms. E) red algae. Answer: C 41) Which of the following is eukaryotic, usually acts as a producer in its ecosystem, and spins via its flagella? A) Dinoflagellate B) Sporozoan C) Apicomplexan D) Cyanobacterium E) Slime mold Answer: A 42) Which of the following is the parasite apicomplexans that causes malaria if it infects a human host? A) Trichomonas B) Paramecium C) Plasmodium D) Giardia E) Pfisteria Answer: C

43) Which protozoan group consists entirely of parasitic forms? A) Ciliates B) Apicomplexans C) Amoebas D) Radiolarians E) Slime molds Answer: B 44) Which of the following is a parasitic protist that is spread by Anopheles mosquitoes? A) Giardia B) Paramecium C) Trichomonas D) Pfisteria E) Plasmodium Answer: E 45) The short, hair-like structures that propel Paramecium through the water are called A) cilia. B) pseudopods. C) vacuoles. D) pseudoplasmodia. E) flagella. Answer: A 46) Calcium carbonate shells and thread-like pseudopods are characteristic of A) radiolarians. B) excavates. C) alveolates. D) foraminiferans. E) euglenids. Answer: D 47) The protist characterized by a silica shell and thread-like pseudopods is a(n) A) euglenid. B) radiolarian. C) excavate. D) foraminiferan. E) alveolate. Answer: B 48) Plasmodial slime molds are described as acellular because they A) have no membranes surrounding theirnuclei. B) reproduce asexually. C) have no nuclei. D) lack DNA. E) are heterotrophic. Answer: A

49) A pseudoplasmodium is a(n) A) aggregation of mycelia. B) group of cellular slime mold cells. C) extension of the slime mold that engulfs prey. D) acellular slime mold. E) disease-causing protist. Answer: B 50) A

forms when an acellular slime mold is exposed to dry conditions or starvation. A) plasmodium B) water mold C) fruiting body D) cellular slime mold

Answer: C 51) Which of the following characteristics distinguishes red algae from diatoms and dinoflagellates? A) One is multicellular, whereas the other is not. B) One is photosynthetic, whereas the other is not. C) One is a protist, whereas the other is not. D) One is eukaryotic, whereas the other is not. E) One lives in an aquatic environment. Answer: A 52) Which group has silica shells similar to those of diatoms? A) Radiolarians B) Apicomplexans C) Ciliates D) Dinoflagellates E) Euglenids Answer: A 53) Which of the following is considered to be most closely related to plants? A) Slime molds B) Euglenids C) Green algae D) Diatoms E) Brown algae Answer: C 54) Which of the following may be parasitic with humans? A) Apicomplexan B) Dinoflagellate C) Diatom D) Amoeba E) Slime mold Answer: A

55) Which of the following has pseudopods? A) Diatom B) Ciliate C) Amoeba D) Apicomplexan E) Slime mold Answer: C 56) The protists are a group that can best be defined as "any eukaryote that is not a plant, animal, or fungus." A) True B) False Answer: A 57) The protists make up an inadequately defined and poorly organized group that biologists will likely reorganize. A) True B) False Answer: A 58) The protists include photosynthetic, parasitic, and pathogenic species. A) True B) False Answer: A 59) Some protists can cause sexually transmitted diseases in humans. A) True B) False Answer: A 60) Alveolates are characterized by pseudopods and silica shells. A) True B) False Answer: B 61) The majority of photosynthesis is carried out by phytoplankton. A) True B) False Answer: A 62) Euglenids have functional eyespots that can discern all colors of visible light and the movement of predators. A) True B) False Answer: B 63) Chalk deposits are formed from the ancient remains of apicomplexans. A) True B) False Answer: B

64) Giardia is found in fresh water and causes an intestinal infection in mammals. A) True B) False Answer: A 65) Diplomonads have two nuclei and move via flagella. A) True B) False Answer: A SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 66) Some protists, such as amoebas, rely on finger-like projections called

for capturing prey and moving.

Answer: pseudopods 67) The process in which photosynthetic bacteria were engulfed by a large cell and formed chloroplasts is called . Answer: endosymbiosis 68) Organisms with pseudopods can surround other organisms and trap them in a

for digestion.

Answer: foodvacuole 69) Excavates lack

Answer: mitochondria 70) The way that Giardia normally infects a host is when the host ingests

in contaminated water.

Answer: cysts 71) Beavers are major carriers of Giardia, which is a member of the group people who drink water that contains the organism's cysts.

that can cause severe diarrhea in

Answer: diplomonad 72) The coral that make up a tropical coral reef can survive only in clear, well-lit waters because of the symbiotic, photosynthetic that live within the tissues of the coral. Answer: dinoflagellates 73) The most complex group of unicellular protists is the

Answer: ciliates 74) The active, feeding form of a(n)

is a thin, multinucleate plasmodium.

Answer: acellular slime mold 75) The cream.

algae are an important source of carrageenan, which is used to thicken paints, cosmetics, and ice

Answer: red 76) The White Cliffs of Dover, England, were formed over millions of years by the accumulation of calcium carbonate shells from . Answer: foraminiferans

77) Trypanosoma is a protistan parasite that causes

in humans.

Answer: African sleeping sickness 78)

is a protistan parasite that causes malaria in humans. Answer: Plasmodium

79) Malaria is caused by a protist that is transmitted by the bite of a(n)

Answer: mosquito 80) The group of protistan aquatic organisms known generally as

produces most of the world's oxygen.

Answer: phytoplankton 81) Paralytic shellfish poisoning is caused by the group of protists known as

Answer: dinoflagellates 82) Anaerobic, flagellated protists such as Trichomonas are grouped as

Answer: parabasalids 83) Oomycetes are primarily

that destroy crops such as grapes and potatoes.

Answer: decomposers 84) The group

includes brown algae and diatoms.

Answer: stramenopiles 85) In rhizarians, the

extend through a calcium carbonate or silica shell.

Answer: pseudopods 86) What types of organisms are classified as protists? Answer: Protists are a catch-all group that contains all eukaryotic organisms that do not fit under the heading of plant, animal, or fungus. 87) By what mechanism(s) do protists reproduce? Answer: Protists reproduce by both asexual methods, which yield two identical organisms, and sexual methods, which combine the genetic material of two organisms. 88) What would life on Earth be like today if eukaryotic protists had not evolved? Answer: Life on Earth would most likely be a diversity of prokaryotes, but no eukaryotes. This is because plants, animals, and fungi likely evolved from protists that subsequently underwent radical changes in their cellular structure and eukaryotic design. 89) How do amoebas differ fromforaminiferans? Answer: Both amoebas and foraminiferans have pseudopods, but amoebas lack the calcium carbonate shell found on foraminiferans. 90) How do kinetoplastids differfrom excavates? Answer: Excavates lack mitochondria, whereas kinetoplastids have mitochondria.

91) One of the techniques for controlling the spread of malaria is to drape netting over the bed. What are the two reasons that this measure would prevent the spread of malaria? Answer: Plasmodium rely on mosquitoes to spread from person to person. The netting would stop the mosquitoes from biting humans, thereby preventing uninfected mosquitoes from picking up the parasite and stopping infected mosquitoes from biting a new host and spreading the infection. 92) Explain the difference between a plasmodium and Plasmodium. Answer: A plasmodium is an acellular slime mold structure made up of thousands of nuclei that are not confined in separate cells. Plasmodium is the genus of apicomplexan protists that causes malaria. 93) What is required to get a cellular slime mold to form a pseudoplasmodium? Answer: The pseudoplasmodium forms when food becomesscarce. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 94) The organisms in the image have shells made of

A) cilia. B) cellulose. C) silica. D) starch. E) calcium carbonate. Answer: C

95) The organisms in the photo belong to the group

A) alveolates. B) rhizarians. C) excavates. D) euglenozoans. E) stramenopiles. Answer: A 96) What characteristic do the organisms in the photos share?

A) Both have calcium carbonate shells. B) Both are photosynthetic. C) Both are parasites. D) Both use pseudopods to capturefood. E) Both are multicellular. Answer: C

97) What characteristic do the organisms in the photos share?

A) Both have calcium carbonate shells. B) Both are parasites. C) Both are prokaryotic. D) Both are photosynthetic. E) Both use pseudopods to capture food. Answer: D 98) While exploring a newly exposed shoreline, you find a new protist. It appears to be multicellular, it uses carbon dioxide from the air to carry out photosynthesis, and its chloroplasts closely resemble those of ferns and grasses. This organism is most likely to belong to the group A) green alga. B) diatom. C) brown alga. D) slime mold. E) apicomplexan. Answer: A

99) After a meal of raw oysters, a woman begins to feel numbness and tingling in her hands and feet. By the time she gets to the hospital, she can no longer move and is having difficulty breathing. The lab finds a protist with two flagella. The organism isa(n) A) radiolarian. B) apicomplexan. C) dinoflagellate. D) euglenozoan. E) brown alga. Answer: C 100) A man is brought to the hospital suffering from nausea, vomiting, and severe stomach cramps. He had recently returned from a hiking trip in northern Minnesota. A sample taken from the man shows a single-celled flagellate organism that lacks mitochondria but has two nuclei. This organism is a(n) A) diatom. B) excavate. C) green alga. D) apicomplexan. E) euglenozoan. Answer: B 101) A shift in weather patterns causes a drought. The normally moist forest becomes dry, with the leaf litter on the forest floor blowing away in high winds. The creek, which normally overflows and floods the forest floor every time it rains, dries up. What would you expect to happen to the slime molds that live in the area? A) The slime molds would shift from the plasmodium and form fruiting bodies. B) The slime mold would begin making red photosynthetic pigments. C) The plasmodium would expand and colonize the now-clean forest floor. D) Dry conditions would encourage the slime mold to photosynthesize. E) The slime mold would begin parasitizing humans. Answer: A 102) A woman develops liver inflammation, a high fever, and a severe decline in red blood cell numbers. Her blood is filled with a parasitic, single-celled organism. When asked about any recent travel, she tells the nurse about her trip to a tropical rain forest. It was a great trip except for the huge number of mosquitoes that bit her. She is probably infected with A) Trichomonas. B) Plasmodium. C) Trypanosoma. D) Giardia. E) Euglena. Answer: B

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) A fertilized egg isa A) sporophyte. B) gametophyte. C) zygote. D) spore. E) gamete. Answer: C 2) In plants, the diploid, multicellular organism is the A) sporophyte. B) gametophyte. C) zygote. D) spore. E) gamete. Answer: A 3) In plants, the haploid, multicellular organism is the A) sporophyte. B) gametophyte. C) zygote. D) spore. E) gamete. Answer: B 4) In plants, the haploid, single-celled product of mitosis is a A) sporophyte. B) gametophyte. C) zygote. D) spore. E) gamete. Answer: E 5) The cells of a gametophyteare A) tetraploid. B) diploid. C) triploid. D) haploid. E) unable to divide by mitosis. Answer: D 6) Specific cells of diploid sporophytes undergo meiosis to produce A) haploid, single-celled spores. B) diploid, multicellular spores. C) diploid, multicellular gametes. D) haploid, single-celled gametes. E) a diploid, single-celledzygote. Answer: A

7) On a trip to the beach, you find a multicellular organism whose cells have chloroplasts and cell walls. Based on this description, you know that the organism could be a brown alga, a red alga, a green alga, or a land plant washed into the ocean. The presence of which of the following would allow you to definitively identify this organism as a plant? A) Starch B) Cellulose C) Multicellular embryo D) Chlorophyll a E) Alternation of generations Answer: C 8) Which of the following supports the idea that land plants arose from green algae? A) Both contain lignin in their cell walls. B) Both photosynthesize. C) Green algae live in freshwater environments, and plants require fresh water. D) Both utilize chlorophylls a and b. E) Both are multicellular. Answer: D 9) The plant kingdom contains all of the descendants of the common ancestor of its members. This kingdom therefore would be called a(n) A) node. B) clade. C) angiosperm. D) sporophyte. E) stoma. Answer: B 10) Green algae are assumed to be ancestors of plants because A) green algae make cellulose and starch. B) the fossil ancestors have beendiscovered. C) green algae are almost exclusively marine. D) lignin is known to occur in some green algae. E) green algae make chitin andlaminarin. Answer: A 11) The closest living relatives to plants are A) amoebas. B) ciliates. C) foraminferans. D) stoneworts. E) red algae. Answer: D 12) Both plants and green algae store food as A) cellulose. B) starch. C) chlorophyll. D) lipids. E) lignin. Answer: B

13) Pollen and seeds evolved in response to A) the evolution of flowers. B) seed predators. C) living on dry land. D) living in a moist environment. E) an increase in pollinators. Answer: C 14) Which of these is an advantage shared by early plants that invaded land? A) Increased sunlight availability B) Fewer predators C) Increased support against gravity D) A and B E) All of the above Answer: D 15) Which of the following is NOT one of the key adaptations to land shared by all land plants? A) Waxy cuticle B) Protected embryos C) A means of taking up nutrients from the soil D) Stomata E) Water transport byxylem Answer: E 16) To control the movement of gases, land plants developed A) stomata. B) acuticle. C) flowers. D) vascular tissue. E) lignin. Answer: A 17) To limit water loss, land plants developed A) stomata. B) acuticle. C) flowers. D) vascular tissue. E) lignin. Answer: B 18) To strengthen the conducting cells and help plants stand erect without water for them to float in, land plants developed A) stomata. B) acuticle. C) flowers. D) vascular tissue. E) lignin. Answer: E

19) Which of the following statements about the function of flowers is TRUE? A) They attract pollinators. B) They protect seeds until they are mature. C) They provide nutrients to theembryo. D) They aid in the dispersal of seeds. E) They attract seed dispersers. Answer: A 20) With respect to plant reproduction, there has been an evolutionary trend toward A) sporophyte prominence. B) greater seed production. C) smaller flowers. D) larger fruits. E) increased pollen production. Answer: A 21) Which of the following is a characteristic of nonvascular plants? A) Stems and leaves B) Extensive root system C) Xylem and phloem D) Small size E) All of the above Answer: D 22) Why are mosses and liverworts dependent on water for reproduction? A) Eggs are passively transported to sperm by water. B) Sperm must swim through water to reach and fertilize eggs. C) Egg and sperm production occurs only when the plants are immersed in water. D) Sperm are passively transported to eggs by water. E) Eggs and sperm are released into water and then unite. Answer: B 23) While walking in a tropical forest, you come upon a 6-meter-tall plant that shows no evidence of seed production. The plant is most likely a(n) A) bryophyte. B) gymnosperm. C) fern. D) alga. E) angiosperm. Answer: C 24) You discover a new species of plant in a tropical rain forest. You observe that it has flagellated sperm and the sporophyte emerges from the gametophyte; however, seeds and xylem tissue is lacking. This plant is probably a(n) A) fern. B) alga. C) gymnosperm. D) bryophyte. E) angiosperm. Answer: D

25) Which of the following weather conditions would you expect to have the greatest negative impact on the sexual reproduction of ferns and mosses? A) Excessively wet and rainy B) Moderate temperatures and rainfall C) Excessively dry for several days D) The shade of a forest E) Above-average temperatures for several days Answer: C 26) Which evolutionary plant innovation eliminated the need for sperm to swim through water in order to fertilize an egg, resulting in plants being truly adapted for reproduction on land? A) Pollen B) Roots C) Independent gametophyte D) Fruit E) Rhizoids Answer: A 27) If you were hiking and wanted to show off your understanding of the differences between gymnosperms and angiosperms, what characteristics could you see with your naked eye that would help you impress your friends? A) Size of the male gametophyte B) Flowers or cones C) Presence or lack of vasculartissues D) Presence or lack ofseeds E) Presence or lack of spores Answer: B 28) In flowering plants, what is the relationship between the sporophyte and gametophyte? A) Flowering plants do not producegametophytes. B) The sporophyte and gametophyte are independent of each other. C) Flowering plants do not producesporophytes. D) The sporophyte is dominant, and the gametophyte is retained on the sporophyte. E) The gametophyte is dominant, and the sporophyte is microscopic. Answer: D 29) Which group of land plants is most restricted to moist environments? A) Vascular plants B) Angiosperms C) Anthophyta D) Bryophytes E) Tracheophytes Answer: D 30) Bryophytes absorb water and nutrients through A) rhizoids. B) roots. C) rhizomes. D) mycorrhizae. E) tracheophytes. Answer: A

31) Which of the following are important reproductive adaptations that allow plants to inhabit terrestrial environments? A) Gametophytes and sporophytes B) Flowers and leaves C) Leaves and stems D) Roots and leaves E) Seeds and pollen Answer: E 32) Which group of plants was the first to produce seeds? A) Lycophytes B) Chlorophytes C) Angiosperms D) Bryophytes E) Gymnosperms Answer: E 33) Which of the following are gymnosperms? A) Ginkgos, conifers, and horsetails B) Cycads, ginkgos, and ferns C) Conifers, ginkgos, and ferns D) Cycads, conifers, and ferns E) Cycads, ginkgos, and conifers Answer: E 34) While walking along a streambed, you encounter a reedy seedless plant. Upon closer inspection, you determine that the stems contain large amounts of silica and have tiny scale-like leaves. This plant is most likely a A) liverwort. B) cycad. C) moss. D) fern. E) horsetail. Answer: E 35) Which of the following groups is represented today by a single species? A) Cycads B) Liverworts C) Ginkgos D) Bryophytes E) Conifers Answer: C 36) Which of the following groups has been planted extensively along U.S. streets because of their resistance to pollution? A) Conifers B) Liverworts C) Ginkgos D) Cycads E) Bryophytes Answer: C

37) What group dominated the Carboniferous period and is now burned as coal? A) Cycads B) Angiosperms C) Seedless vascular plants D) Conifers E) Algae Answer: C 38) How do ferns differ from other seedless vascular plants? A) Their sperm are flagellated. B) They lack xylem. C) The sporophyte is dominant. D) They have broad leaves. E) Their flowers are microscopic. Answer: D 39) Which group does NOT depend on water for reproduction? A) Bryophytes B) Club mosses C) Ferns D) Flowering plants E) Algae Answer: D 40) Why can't you buy fern seeds from a garden supply store? A) Fern seeds must stay moist. B) The seeds are extremely rare. C) Ferns do not produce seeds. D) Fern seeds do not survive long after they are produced. E) The seeds are too small to package. Answer: C 41) In angiosperms, what is the male gametophyte? A) Pollen B) A seed C) A flower D) The anther E) Sperm Answer: A 42) A fruit is a A) female gametophyte. B) seed. C) mature ovary. D) plant embryo. E) mature ovule. Answer: C

43) Fruit production requires precious resources. What important benefit does fruit provide? A) Is a means of seeddispersal B) Attracts pollen eaters C) Keeps the seed moist D) Prevents consumption of enclosed seeds E) Feeds theembryo Answer: A 44) Most gymnosperms are pollinated by A) shrews. B) insects. C) birds. D) lizards. E) wind. Answer: E 45) You've stumbled upon a thick mat of moss in the woods. Upon closer inspection, you observe sporophytes emerging from the gametophytes. From your previous biology course, you know that the sporophyte is attached to a(n) A) flower. B) female cone. C) embryo sac. D) antheridium. E) archegonium. Answer: E 46) Which of the following is most likely to be successful and thrive in a desert ecosystem? A) Green alga B) Fern C) Horsetail D) Angiosperm E) Conifer Answer: D 47) Which of the following relies on the wind for pollination? A) Tulip B) Pine tree C) Stinking corpse lily D) Gardenia E) Magnolia tree Answer: B 48) Which of the following is technically NOT a fruit? A) Pumpkin B) Tomato C) Cucumber D) Lettuce E) Green pepper Answer: D

49) Why might a seed be covered in prickly hooks? A) To allow it to float on water B) To keep it from being eaten C) To help the seed germinate D) To aid in seed dispersal E) To attract insects Answer: D 50) Gnetophytes are A) angiosperms. B) bryophytes. C) ferns. D) seedless vascular plants. E) nonflowering seed plants. Answer: E 51) What major adaptations contributed to the success of the angiosperms? A) Flowers and fruits B) Broad leaves C) Sap containing "antifreeze" D) A and B E) A and C Answer: D 52) Ginkgos are classified as A) angiosperms. B) bryophytes. C) seedless vascular plants. D) gymnosperms. E) ferns. Answer: D 53) Horsetails are classified as A) angiosperms. B) bryophytes. C) seedless vascular plants. D) gymnosperms. E) ferns. Answer: C 54) Cycads are classified as A) angiosperms. B) bryophytes. C) seedless vascular plants. D) gymnosperms. E) ferns. Answer: D

55) Roses are classified as A) angiosperms. B) bryophytes. C) seedless vascular plants. D) gymnosperms. E) ferns. Answer: A 56) A complete lack of vascular tissue is characteristicof A) mosses. B) angiosperms. C) cycads. D) ginkgos. E) ferns. Answer: A 57) Pollen production by the anthers of a flower is characteristic of A) conifers. B) ginkgos. C) angiosperms. D) ferns. E) mosses. Answer: C 58) Which of the following is NOT an ecological service performed by plants? A) Help create and maintain soil B) Reduce erosion by wind and water C) Capture solar energy D) Increase soil humidity E) Produce oxygen as a by-product of photosynthesis Answer: D 59) Which of the following is a plant-derived heart medication? A) Morphine B) Codeine C) Digoxin D) Vinblastine E) Taxol Answer: C 60) Plants provide us with a variety of goods. Which of the following is NOT provided by plants? A) Nylon B) Cotton C) Wood D) Pleasure E) Cooking oil Answer: A

61) The characteristic that sets plants apart from photosynthetic protists is the multicellular, dependent embryo. A) True B) False Answer: A 62) The haploid generation of a plant is called the sporophyte. A) True B) False Answer: B 63) The cuticle of leaves and stems is one modification that enabled plants to move onto land. A) True B) False Answer: A 64) One function of the plant cuticle is to increase water uptake by roots. A) True B) False Answer: B 65) Seeds allowed plants to colonize dry land. A) True B) False Answer: A 66) Mosses produce large amounts ofpollen. A) True B) False Answer: B 67) In nonvascular plants, sperm are formed in antheridia by mitosis. A) True B) False Answer: A 68) In nonvascular plants, sperm are formed in the archegonia by meiosis. A) True B) False Answer: B 69) Club mosses and horsetails have vascular tissue. A) True B) False Answer: A 70) Cycads attract pollinators with large, fragrant flowers. A) True B) False Answer: B

71) The only seedless vascular plants with broad leaves are ferns. A) True B) False Answer: A 72) Fruits are a method of pollen dispersal. A) True B) False Answer: B 73) Some flowers are pollinated by bats. A) True B) False Answer: A 74) Plants remove carbon dioxide from the atmosphere. A) True B) False Answer: A 75) Plants increase the rate at which water leaves terrestrial ecosystems. A) True B) False Answer: B SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 76) You find a multicellular, eukaryotic organism that carries out photosynthesis and produces dependent embryos. It is classified as a(n) . Answer: plant 77) The

generation of a plant is diploid.

Answer: sporophyte 78) The

generation of a plant is haploid.

Answer: gametophyte 79) Gametophytes are multicellular plants that develop from reproductive cells called

Answer: spores 80) Plants produce

by mitosis and

by meiosis.

Answer: gametes; spores 81) Sporophytes are multicellular plants that produce

Answer: spores 82) A group containing all the descendants of the same common ancestor is known as a Answer: clade

83) Land plants are believed to have evolved from

Answer: green algae, or stoneworts 84) To reduce water loss, stems and leaves are covered with a(n)

Answer: cuticle 85) The conducting tissues of vascular plants are rigid because they contain

in their cell walls.

Answer: lignin 86) A mature pine tree is part of the

generation.

Answer: sporophyte or diploid 87) Antheridia are structures that produce

Answer: sperm 88) The

are the most diverse seedless vascular plants.

Answer: ferns 89) Conifer seeds develop in reproductive structures called

Answer: cones 90) Angiosperms produce pollen instructures called

Answer: anthers 91) Ephedra, used by humans as a stimulant and appetite suppressant, is a member of the gymnosperms.

group of

Answer: gnetophyte 92) Most gymnosperms are pollinated by wind, whereas most angiosperms are pollinated by

Answer: animals 93) In flowering plants, a ripened ovary is known as a

Answer: fruit 94) During photosynthesis, plants remove

from and add

to the atmosphere.

Answer: carbon dioxide; oxygen 95) Taxol and vinblastine are plant-derived medicines usedto treat

Answer: cancer 96) What evidence supports the idea that members of the plant kingdom evolved from ancestral green algae? Answer: Plants and green algae have similar DNA sequences, store starch, have cellulose in their walls, and use the same photosynthetic pigments. 97) Why was the evolution of lignin-impregnated cell walls significant? Answer: Lignin provides support for plants, enabling them to grow to great heights on land.

98) What advantage do seed plants have over spore-forming plants? Answer: Seeds tolerate drying better and live longer than spores. Seeds can take advantage of animals for dispersal, whereas spores are too small and lacking in nutrients to interest animal carriers. 99) Explain the difference between an angiosperm seed and a gymnosperm seed. Answer: Gymnosperm seeds develop in cones and lack fleshy covering. Angiosperm seeds develop within the ovary to form a fruit. 100) In some areas of the world where there are large numbers of pine trees, in the spring everything is covered with a yellow dust that turns out to be pine pollen. Why must conifers produce so much pollen, and why doesn't a field of flowers produce so much pollen? Answer: Pines are pollinated by the wind, so they must produce large excesses of pollen. Field flowers are pollinated by insects and therefore don't have to produce so much pollen. 101) Explain how bryophytes are an intermediate between green algae and terrestrial plants. Answer: Bryophytes are land-dwelling plants but must be close to water because they are nonvascular and lack the ability to transport water over long distances. Like green algae, they also produce swimming sperm, which means water must be available for fertilization to occur. 102) Explain the evolutionary importance ofseeds. Answer: Seeds enabled plants to thrive on land because the plant embryos are protected from drying out and survive on the food stored inside the seed until growing conditions are favorable. The seed coat helps regulate the timing of seedgermination. 103) What methods do angiosperms use to disperse seed? Answer: Angiosperm seeds are spread via wind, water, ingestion of fruits by birds and animals, and hitching a ride on fur, feathers, and clothing. 104) Why are ferns not well adapted to desert areas? Answer: Ferns have limited vascular elements and are not very effective at transporting water. Most ferns lack a heavy cuticle to prevent drying under low humidity. Ferns require liquid water to transport the sperm. 105) With regard to reproduction, how do gymnosperms differ from angiosperms? Answer: Gymnosperms do not produce flowers, whereas angiosperms do. 106) What characteristics allow conifers to dominate cold, dry habitats? Answer: Conifers have the ability to photosynthesize year round, their leaves form small needles protected with a heavy waxy cuticle, and their resin acts as an antifreeze. 107) How does photosynthesis benefit nonphotosynthetic organisms such as humans? Answer: Plants convert solar energy to chemical energy in the form of sugars and starches, which provide food for humans. During photosynthesis, oxygen is given off as a waste product. This provides the oxygen we breathe. 108) How do humans benefit from growing plants? Answer: Plants are used for fuels, food, medicines, shelter, and pleasure.

109) In the 1800s, northern Minnesota was covered with heavy forests. After the forests were logged off, the land was sold for farms. The majority of the farms failed because the land became waterlogged. Why did this happen? Answer: Plants absorb and hold huge amounts of water. Without the trees to absorb the water, the water table rose and the land flooded. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

110) Based on the evolutionary tree, the closest relatives of seed plants are the A) liverworts. B) ferns. C) mosses. D) green algae. Answer: B 111) Based on the evolutionary tree, angiosperms are most closely related to A) gymnosperms. B) green algae. C) mosses. D) liverworts. E) ferns. Answer: A 15

112) The eucalyptus flower in the photograph shown here is most likely pollinated by

A) humans. B) water. C) wind. D) insects. E) frogs. Answer: D

113) The fruit in the photograph shown here has evolved for dispersal by

A) frogs. B) water. C) insects. D) wind. E) humans. Answer: D 114) You observe a 1-inch-tall plant in the woods. This plant is part of a mass of similar small plants covering an area of several square feet. It is very flexible and does not easily stand upright by itself. Upon examining the tiny, flat, leaflike structures of this plant, you see no veins. There is no evidence of seeds, but at the end of a little stalk on the tip of the plant, there is some sort of spore-bearing structure. This plant is probably a(n) A) fern. B) angiosperm. C) bryophyte. D) gymnosperm. E) alga. Answer: C 115) While walking in a forest, you find a plant with what appears to be unfertilized seeds located at the bases of woody scales exposed to the air. Yellow dust-like particles coat the surface of the unfertilized seeds. This plant is probably a(n) A) seedless vascular plant. B) gymnosperm. C) bryophyte. D) angiosperm. E) alga. Answer: B

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Fungal cell walls are different from plant cell walls because fungal walls contain A) cellulose, whereas plant walls havepectin. B) chitin, whereas plant walls have cellulose. C) cellulose, whereas plant walls have chitin. D) glycogen, whereas plant walls havecellulose. E) chitin, whereas plant walls have starch. Answer: B 2) Which of the following features are characteristic of fungi? A) No cell walls, parasitic, heterotrophic B) Cell walls, photosynthesis, and usually filamentous bodies C) Cell walls, chemosynthetic, heterotrophic D) Cell walls, feeding by absorption, and usually filamentous bodies E) No cell walls, feeding by absorption, chemosynthesis Answer: D 3) The body of a fungus is generally composed of A) cellulose. B) hyphae. C) mold. D) mycorrhizae. E) vascular tissue. Answer: B 4) The interwoven mass of cells that forms large structures such as an earthstar or a mushroom is a A) hypha. B) septum. C) mycelium. D) spore. E) root. Answer: C 5) Some fungi are predators (not parasites) of A) nematodes (roundworms). B) chestnut and elm trees. C) humans. D) spiders. E) wheat. Answer: A 6) Which polysaccharide is produced by both fungi and arthropods? A) Chitin B) Cellulose C) Fructose D) Glucose E) Glycogen Answer: A

7) When you eat mushrooms on your pizza, you are technically eating the A) seeds. B) roots. C) mycelium. D) chloroplasts. E) fungal leaves. Answer: C 8) Fungi usually obtain food by A) photosynthesis. B) chemosynthesis. C) digesting it externally and then absorbing it. D) absorbing it and then digesting it within fungal cells. E) producing antibiotics that internally destroy bacteria. Answer: C 9) Both bacteria and fungi digest food by A) eating only small organisms that they can engulf. B) forming food vacuoles through phagocytosis. C) photosynthesis. D) ingesting previously decomposed molecules. E) secreting enzymes and then absorbing the smaller molecules. Answer: E 10) Moldseasily contaminate foods because fungi A) are not visible. B) have haploid bodies. C) are unaffected by cooking. D) produce huge numbers of airbornespores. E) produce temporary, visible reproductive structures. Answer: D 11) Fungi are similar to plants because both A) have chloroplasts in their cells. B) liberate nutrients from dead tissues. C) are important producers in theirecosystems. D) produce embryos when they reproduce. E) have cell walls surrounding their plasma membranes. Answer: E 12) The dominant generation in the fungal life cycle is usually A) unicellular. B) a sporophyte. C) haploid. D) polyploid. E) diploid. Answer: C

13) Which of the following sequences describes sexual reproduction in the fungal life cycle? A) The haploid zygote divides by meiosis to form haploid spores. B) Haploid gametes divide by meiosis to produce a diploid zygote, which grows by mitosis to produce diploid mycelia. C) Free-swimming gametes fuse to form a diploid zygote, which grows by mitosis. D) The diploid zygote divides by meiosis to form haploid spores, which produce haploid mycelia through mitosis. E) Diploid spores divide by meiosis to form haploid gametes, which join to form mycelia. Answer: D 14) The mat-like structure composed of hyphal threads that forms the body of most fungi is called a(n) A) septum. B) mycelium. C) ascus. D) basidium. E) zygospore. Answer: B 15) Which fungal group produces swimming, flagellated spores? A) Ascomycetes B) Glomeromycetes C) Zygomycetes D) Chytrids E) Basidiomycetes Answer: D 16) In which environment would you most likely find chytrids? A) A well-used gym bag B) A basket of overripe fruit C) A warm swamp D) The back of the refrigerator Answer: C 17) According to the fossil record, the most ancient group of fungi is probably the A) zygomycetes. B) glomeromycetes. C) basidiomycetes. D) chytrids. E) ascomycetes. Answer: D 18) The worldwide die-off of frogs has been traced to infection by A) glomeromycetes. B) zygomycetes. C) basidiomycetes. D) ascomycetes. E) chytrids. Answer: E

19) A zygosporangium is produced by A) meiosis of hyphae. B) mitosis of hyphae. C) meiosis of megaspores. D) the union of two haploidhyphae. E) the union of egg andsperm. Answer: D 20)

form beneficial symbiotic relationships with plant roots. A) Chytrids B) Zygomycetes C) Glomeromycetes D) Ascomycetes E) Basidiomycetes Answer: C

21) When zygosporangia germinate, they must undergo A) sporulation B) mitosis C) fertilization D) meiosis Answer: D 22) Which fungal phylum usually carries on sexual reproduction? A) Zygomycetes B) Chytrids C) Basidiomycetes D) Glomeromycetes E) Ascomycetes Answer: C 23) The name sac fungi is appropriate for the ascomycetes because A) it is best to carry them in a sack. B) they produce seeds in saclikestructures. C) they grow well in closedbags. D) the body of the fungus is a saclike shape. E) they produce spores in saclike structures. Answer: E 24) In ascomycetes, theascus functions in A) sexual reproduction. B) vegetative growth. C) asexual reproduction. D) photosynthesis. E) digestion. Answer: A

before forming hyphae.

25) The specialized reproductive structures of club fungi are called A) mycelia. B) basidia. C) zygospores. D) toadstools. E) asci. Answer: B 26) The specialized reproductive structures of sac fungi are called A) mycelia. B) zygospores. C) toadstools. D) basidia. E) asci. Answer: E 27) Which group of fungi appears to lack asexual reproduction? A) Ascomycetes B) Glomeromycetes C) Chytrids D) Basidiomycetes E) All fungi have asexual reproduction. Answer: B 28) Black bread molds produce diploid reproductive structures called A) toadstools. B) asci. C) mycelia. D) zygosporangia. E) basidia. Answer: D 29) The conspicuous structures on the surface of a dead tree that indicate a fungus is growing inside are for A) reproduction. B) show only. C) feeding. D) defense. E) pollination. Answer: A 30) How are lichens and mycorrhizae similar? A) Both are pioneer species that colonize bare rock. B) Both form symbiotic relationships with photosynthetic species. C) Both parasitize live plants, eventually killing them. D) Both are saprophytes that decompose dead materials. Answer: B

31) What are lichens? A) Algae B) A symbiotic association of algae and Archaea C) A symbiotic association of algae and fungi D) Fungi E) Archaea Answer: C 32) Mycorrhizae are symbiotic associations between A) algae and plant roots. B) algae and fungi. C) fungi and plant stems. D) animals and fungi. E) plant roots and a fungus. Answer: E 33) Which of the following are among the first organisms to colonize barren habitats? A) Small mammals B) Plants C) Fungi D) Mushrooms E) Lichens Answer: E 34) Which fungal group is most commonly found in lichens? A) Zygomycetes B) Ascomycetes C) Chytrids D) Basidiomycetes E) Glomeromycetes Answer: B 35) Mycorrhizae surround and infiltrate the A) flowers B) roots C) leaves D) stems E) seeds

of vascular plants.

Answer: B 36) Mycorrhizae associations are A) common; at least 80% of the species of plants form these associations. B) absolutely necessary for survival. C) very unusual. D) common only in nutrient-rich environments. E) common only to species, such as grasses. Answer: A

37) The photosynthetic component of a lichen is a(n) A) basidiomycete. B) ascomycetes. C) alga or cyanobacterium. D) small plant. E) arthropod or protist. Answer: C 38) Fungi that live inside plant leaves and provide protection from insects are A) endophytes. B) saprophytes. C) mycorrhizae. D) lichens. E) photosynthetic. Answer: A 39) Why are fungi important in recycling woody plants? A) Woody plants occupy the same environment as fungi. B) Fungi are the only organisms capable of digesting both cellulose and lignin. C) Fungi have the internal digestion necessary to digest wood. D) Fungi digestchloroplasts. Answer: B 40) If there were no fungi, which of the following would occur? A) Oxygen production would stop. B) Grazing animals would be unable to digest plants. C) Nutrient recycling would stop. D) Plants would overrun the Earth. Answer: C 41) The importance of fungi to ecosystems is mostly as a(n) A) symbiote. B) predator. C) decomposer. D) producer. E) parasite. Answer: C 42) If a strong fungicide is released and eliminates all the fungi in an ecosystem, which of the following is likely to happen? A) Improved soil fertility B) Faster breakdown of leaf litter C) Increased rate of photosynthesis D) An accumulation of dead and discarded plant and animal tissues E) Improved growth of plantspecies Answer: D

43) Which of the following is an example of a parasitic fungal disease? A) Athlete's foot B) Malaria C) Herpes D) Sleeping sickness E) Trichinosis Answer: A 44) Single-celled fungi are known as A) spores. B) club fungi. C) chytrids. D) prokaryotes. E) yeasts. Answer: E 45) Ascomycetes produce which of thefollowing? A) Basidia B) Smuts and rusts C) Black bread mold D) Chytrids E) Penicillin Answer: B 46) Which fungi produces toxins (including LSD) that can cause convulsions, hallucinations, and death if consumed by a person? A) Candida albicans B) Chytrid fungi C) Claviceps purpurea D) Deadly night shade E) Aspergillus Answer: C 47) The antibiotic penicillin was originally derived from A) chemical factories. B) fungi. C) Archaea. D) plants. E) bacteria. Answer: B 48) The highly toxic Aspergillus infects A) milk. B) peanuts. C) wheat. D) human skin. E) bread. Answer: B

49) Aflatoxins, which are highly toxic, carcinogenic compounds, come from A) corn smut. B) Claviceps purpurea. C) Amanita. D) Candida albicans. E) Aspergillis. Answer: E 50)

causes human yeast infections. A) Aspergillus B) Amanita C) Claviceps purpurea D) Candida albicans Answer: D

51) Which of the following fungus causes ergot poisoning, a common cause of death in Europe in the Middle Ages? A) Amanita B) Truffles C) Candida albicans D) Claviceps purpurea E) Aspergillus Answer: D 52) Rusts and smuts are examplesof A) fungal plant diseases. B) human pathogens. C) lichens. D) yeasts. E) mycorrhizae. Answer: A 53) What gives blue cheeses such as Roquefort and Stilton their unique flavor? A) Ascomycete mold B) Chytrids C) Yeast D) Mushrooms E) Alcohol Answer: A 54) Which of the following is a by-product of yeast fermentation? A) Sugar B) Carbon dioxide C) Chitin D) Oxygen gas E) Carbon monoxide Answer: B

55) During alcohol fermentation, yeasts ferment A) complex carbohydrates. B) oxygen gas. C) carbon dioxide. D) chitin. E) sugar. Answer: E 56) What creates the holes inbread? A) Alcohol B) Yeast C) Oxygen gas D) Air E) Carbon dioxide Answer: E 57) Histoplasmosis is caused by A) carbon dioxide inhalation. B) inhaling certain fungal spores. C) ergot poisoning. D) eating too much yeast. E) Amanita-induced liver failure. Answer: B 58) Which fungus group is responsible for Dutch elm disease and the destruction of the American elm? A) Ascomycetes B) Basidiomycetes C) Chytrids D) Glomeromycetes E) Zygomycetes Answer: A 59) Fungal hyphae usually are diploid. A) True B) False Answer: B 60) Fungi are heterotrophs, but they do not ingest their food. A) True B) False Answer: A 61) Fungal cell walls are composed of lignin. A) True B) False Answer: B 62) Chytrids are the fungal species best adapted to colonizing dry environments. A) True B) False Answer: B 10

63) Glomeromycetes reproduce by basidiospores. A) True B) False Answer: B 64) Fairy rings are produced by basidiomycetes. A) True B) False Answer: A 65) Yeasts form a symbiotic relationship with a bacteria. A) True B) False Answer: B 66) Mycorrhizae are plant parasites. A) True B) False Answer: B 67) Lichens can form from the symbiotic relationship between a photosynthetic bacterium and a fungus. A) True B) False Answer: A 68) Mycorrhizae help plants obtain water from the soil. A) True B) False Answer: A 69) Fungi that feed on dead tissue are saprophytes. A) True B) False Answer: A 70) Ringworm is a fungal infection of the skin. A) True B) False Answer: A SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 71) Hyphae are divided into cells by

Answer: septa 72) During asexual reproduction, fungi produce haploid spores via

Answer: mitosis 73) During sexual reproduction, fungi produce haploid spores via Answer: meiosis

74) Chytrids reproduce by swimming

, which sets this group apart from other fungi.

Answer: spores 75) In black bread molds, the

produce haploid spores for asexual reproduction.

Answer: sporangia 76) During sexual reproduction, the spores of the sac fungi develop in

Answer: asci 77) In a lichen,

produce sugars for the fungal partner.

Answer: cyanobacteria or algae 78) It is hypothesized that

associations may have helped plants colonize dry land.

Answer: mycorrhizal 79) Fungi that live symbiotically inside plants are

Answer: endophytes 80) In the environment, fungi that feed off dead organic material are important

Answer: decomposers 81) Often, the first organisms to colonize a new environment are

Answer: lichens 82) Truffles, the spore-containing structure of a

, are eaten as a delicacy.

Answer: ascomycete 83)

is a single-celled fungus that produces yeast infections. Answer: Candida albicans

84) Ergot poisoning is caused by a

produced by the ascomycete Claviceps purpurea.

Answer: toxin 85) The mold used to produce blue cheeses such as Roquefort and Stilton reproduces sexually via

Answer: asci, or ascospores 86) Originally, fungi were considered a type of plant. Now they are classified in their own kingdom. What characteristics differentiate fungi from plants? Answer: Plant cell walls are based on cellulose; fungal cell walls are based on chitin. Plants have chloroplasts and carry on photosynthesis; fungi lack chloroplasts and obtain energy from other organisms. 87) How do ascomycetes differ fromglomeromycetes? Answer: Ascomycetes reproduce sexually by producing spores in terminal sacs, whereas glomeromycetes live in the roots of plants, formingmycorrhiza. 88) How do ascomycetes differ frombasidiomycetes? Answer: Ascomycetes reproduce sexually by producing several spores in terminal sacs. Basidiomycetes produce club-shaped structures.

89) How do glomeromycetes differ frombasidiomycetes? Answer: Glomeromycetes live in the roots of plants, forming mycorrhiza, whereas basidiomycetes produce club-shaped structures. 90) How are chytrids different from glomeromycota, basidiomycota, and ascomycota? Answer: Chytrids produce flagellated, swimming spores, a trait seen in only a few fungi, such as chytrids, rumen fungi, and blastoclades. 91) What roles do fungi play in the environment? Answer: Fungi recycle nutrients by decomposing dead organisms, they form symbiotic relationships that provide nutrients to plants, and they act as pioneer species. 92) Why do fungi have the ability to decompose materials such as cotton and wool that other organisms cannot? Answer: Fungi contain both protease and cellulase enzymes not found in other organisms. 93) What role do mycorrhizae play in helping plants survive? Answer: Mycorrhizae help plants obtain nutrients such as nitrogen and phosphorus from the environment and improve water uptake by plant roots. 94) We tend to think of fungi as being bad. What are some ways in which fungi benefit humans? Answer: Fungi provide us with antibiotics, they flavor our foods (blue cheese, miso, etc.), and they ferment plant products to produce bread, wine, and beer. 95) Beer is sometimes called liquid bread.Why? Answer: Both beer and bread are made from yeast-fermented grains. 96) Why is it unsafe to collect wild mushrooms without expert training? Answer: Poisonous mushrooms can closely resemble those that are safe to eat. It often requires an expert to differentiate them. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

97) Based on the illustration shown here, basidiomycetes are most closely related to

A) algae. B) zygomycetes. C) ascomycetes. D) glomeromycetes. E) chytrids. Answer: C

98) The structure shown in the photograph is a(n)

A) lichen. B) ascus. C) mycelium. D) chytrid. E) alga. Answer: C 99) The structure in the photograph is a(n)

A) zygosporangium. B) glomeromycete. C) seed. D) basidium. E) ascus. Answer: A

100) This organism represents

A) a symbiotic relationship between a fungus and an alga. B) chytrids. C) a severe plant pathogen. D) sexual reproduction in basidiomycetes. E) a mycorrhizeal association. Answer: A 101) The fungi in the photographs here are examples of

A) reproductive structures. B) hyphae. C) mycelia. D) mushrooms. E) fairy rings. Answer: A

102) This photograph shows a glomeromycete fungus growing in the cell of a plant. The fungus will help the plant get water and minerals, and the plant will supply the fungus with some sugar. This relationship is known as

A) a Blastoclade. B) parasitic. C) a lichen. D) autotrophic. E) a mycorrhiza. Answer: E

103) According to the figure, the life cycle of a typical basidiomycete, basidiomycetes are life cycle. A) mushrooms B) diploid C) nuclei D) haploid E) ascomycetes

for most oftheir

Answer: D 104) According to the figure, the life cycle of a typical basidiomycete, which of the following statements is TRUE about sexual reproduction? A) It does not include meiosis. B) It results in diploid hyphae. C) It begins when hyphae form a mushroom. D) It begins in the gills of the mushroom. E) It begins when a (-) hypha and a (+) hypha meet. Answer: E

105) You must decide how to classify a newly discovered organism, but you have only limited test materials to help you make your decision. Chemical A glows if a nuclear envelope is present. Chemical B turns blue in the presence of chloroplasts. Chemical C fizzes when mixed with chitin. After testing the organism, you find out that it glows, doesn't turn blue, and fizzes. You classify this organism as a A) zooflagellate. B) slime mold. C) fungus. D) diatom. E) bacterium. Answer: C 106) You find a new organism. It gains nutrients by secreting enzymes outside of itself and absorbing the digested product. It is eukaryotic and has a cell wall containing chitin. It reproduces with flagellated, swimming spores. You classify the new organism as a(n) A) ascomycota. B) mushroom. C) basidiomycota. D) rumen fungus. Answer: D 107) A more or less circular ring of mushrooms appears in your yard, apparently overnight. The circle is several yards in diameter. The mushrooms appear to be producing spores. What is the most likely explanation for this circle of mushrooms? A) The mushrooms are all part of the same organism, with mycelia radiating out from the location of a germinated spore. B) Mushroom spores were dropped by a circling bird, thus explaining the circular shape of the group of mushrooms. C) The circle represents the fungal life cycle. D) One mushroom in the circle reproduced sexually to make all the other mushrooms in the circle. E) The mushroom plants in the center of the circle were older and have already died or been eaten by herbivores. Answer: A

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) A multicellular organism that lacks cell walls and obtains energy by eating other organisms is a(n) A) chytrid. B) alga. C) fungus. D) plant. E) animal. Answer: E 2) The only animals that lack tissues are A) nematodes. B) sponges. C) cnidarians. D) chytrids. E) chordates. Answer: B 3) A

is an organism whose body cavity forms between the body wall and the digestive system. A) sponge B) nematode C) deuterostome D) protostome E) hermaphrodite

Answer: D 4) In the animal kingdom, cephalizationis A) concentration of sensory structures in the head. B) development of eyes at the anterior end of the organism. C) evolutionary development of a netlike system of veins. D) development of a body that has paired structures forming a side-to-side mirror image. E) the ability to respond rapidly to external stimuli. Answer: A 5) One trend in the evolution of animals is the increase in the number of tissue (germ) layers during embryonic development. Flatworms and more complex animals have layers. A) two B) three C) four D) five E) six Answer: B 6) Organisms that are radially symmetrical have A) two B) three C) four D) five E) six

embryonic germ layers.

Answer: A

7) The skin and nervous tissues develop from which germ layer? A) Protoplasm B) Endoderm C) Ectoderm D) Mesoderm E) Mesoglea Answer: C 8) Which of the following animal phyla is distinguished by a lack of tissues? A) Sponges B) Echinoderms C) Roundworms D) Flatworms E) Annelids Answer: A 9) Damage to the embryonic ectoderm would show up as damage to which adult body tissues? A) Body cavity linings B) Muscles C) Skeletal tissue D) Nervous tissue E) Circulatory tissue Answer: D 10) Between the organs and the body wall, complex animals have a body cavity called a A) mesoglea. B) thorax. C) mesoderm. D) cnidarian. E) coelom. Answer: E 11) Which germ layer gives rise to the muscle layer of the uterus? A) Mesoderm B) Endoderm C) Ectoderm Answer: A 12) How many tissue layers are in the embryos of sponges? A) None B) One C) Two D) Three E) Four Answer: A

13) An arthropod embryo has A) no B) one C) two D) three E) four

germ layer(s).

Answer: D 14) Anemones have no A) mesoderm. B) ectoderm. C) endoderm. Answer: A 15) A cnidarian, which is radially symmetrical, has A) no B) one C) two D) three E) four

germ layer(s).

Answer: C 16) The common ancestor of sponges and other animals was probably A) multicellular without tissues. B) unicellular. C) multicellular with tissues and a few organ systems. D) multicellular with tissues and many organ systems. E) multicellular with tissues but without organ systems. Answer: A 17) All animals with tissueshave A) bilateral symmetry. B) radial symmetry. C) symmetrical bodies. D) two germ layers. E) three germ layers. Answer: C 18) Which of the following characteristics is associated with all animals that are bilaterally symmetrical at some point in their life cycle? A) Lack of organs B) Gastrovascular cavity C) Coelom D) Cephalization E) Mesoderm Answer: E

19) Which of the following characteristics is often associated with animals that are radially symmetrical? A) Sessile or otherwise nonmobile B) Mesoderm C) Cephalization D) Mobility E) Gastrovascular cavity Answer: A 20) The major difference between protostomes and deuterostomes is the A) presence or absence of acoelom. B) type of body symmetry. C) way the body cavity forms. D) presence or absence of tissues. E) presence or absence of cephalization. Answer: C 21) Ecdysozoans A) periodically shed their outer bodycovering. B) have a body cavity that forms from the digestive system. C) include mollusks, annelids, and flatworms. D) have a special feeding structure. E) have trochophore larva. Answer: A 22) Which of these groups is characterized by having no body cavity? A) Roundworms B) Cnidarians C) Annelids D) Arthropods E) Chordates Answer: B 23)

are characterized by having apseudocoelom. A) Cnidarians B) Roundworms C) Arthropods D) Annelids E) Chordates Answer: B

24) Which of these groups is characterized by having a TRUE coelom? A) Flatworms B) Arthropods C) Roundworms D) Cnidarians E) Sponges Answer: B

25) Which of these groups is characterized by a lack of symmetry (neither radial nor bilateral)? A) Arthropods B) Flatworms C) Chordates D) Sponges E) Cnidarians Answer: D 26) The simplest multicellular animals that have only a few different cell types are A) anemones. B) sea squirts. C) flatworms. D) jellyfish. E) sponges. Answer: E 27) Giant squids are classified as A) arthropods. B) mollusks. C) platyhelminthes. D) echinoderms. E) chordates. Answer: B 28) The currents of water (containing food) that pass through a sponge are maintained by A) a water-vascular system. B) the osculum. C) ganglia. D) medusae. E) collar cells. Answer: E 29) Sponges have A) a nerve net. B) an exoskeleton. C) a gastrovascular cavity. D) spicules. E) muscles. Answer: D 30) Which cnidarian is the basis of many impressively diverse marine habitats? A) Coral B) Hydra C) Anemone D) Sea cucumber E) Jellyfish Answer: A

31) Hydra, anemones, and jellyfish are in the phylum A) Protista. B) Porifera. C) Cnidaria. D) Flagellates. E) Platyhelminthes. Answer: C 32) A cnidarian that builds a calcium carbonate skeleton is a(n) A) coral. B) crab. C) oyster. D) snail. E) clam. Answer: A 33) Flatworms lack A) a respiratory system. B) the ability to move. C) a reproductive system. D) a nervous system. E) a digestive cavity. Answer: A 34) What causes schistosomiasis, a devastating disease that affects about 200 million people in tropical regions? A) Amoebas B) Nematodes C) Echinoderms D) Trichinella E) Parasitic flatworms called blood flukes Answer: E 35) The phylum Nematoda includes which of the following very common organisms, some of which are parasitic and most of which are often found in soil? A) Earthworms B) Roundworms C) Segmented worms D) Tapeworms E) Flatworms Answer: B 36) Worms with a well-developed circulatory system (including five pairs of hearts) are A) nematodes. B) annelids. C) platyhelminths. D) echinoderms. E) eels. Answer: B

37) Which invertebrate animal group is characterized by having a closed circulatory system? A) Platyhelminthes B) Echinodermata C) Arthropoda D) Annelida E) Nematoda Answer: D 38) A(n) provides support and protection to arthropods. A) shell B) hydrostatic skeleton C) cytoskeleton D) exoskeleton E) epidermis Answer: D 39) Insects are members of thegroup A) Echinodermata. B) Arachnida. C) Arthropoda. D) Mollusca. E) Annelida. Answer: C 40) An animal such as a grasshopper can conserve water because it has an elaborately branching system of tubes within its body that it uses for gas exchange. These tubes are called A) kidneys. B) book lungs. C) tracheae. D) flame cells. E) gills. Answer: C 41) Which of the following animals are arachnids? A) Beetles B) Grasshoppers C) Flukes D) Spiders E) Wasps Answer: D 42) Which of the following animals uses a radula to scrape food into its mouth? A) Rat B) Snail C) Starfish D) Scallop E) Octopus Answer: B

43) The taxonomic group that contains the most species and seemingly most intelligent invertebrates is A) Uniramia. B) Cephalopoda. C) Chordata. D) Aves. E) Gastropoda. Answer: B 44) The animals most like the ancestral protist colonies that likely gave rise to all animals are A) chordates. B) sponges. C) arthropods. D) nematodes. E) echinoderms. Answer: B 45) What distinguishes a free-living flatworm from other organisms? A) A cuticle B) A tubular gut C) A coelom D) Eyespots E) Hooks Answer: D 46) Adult echinoderms that have radial symmetry lack A) nervous tissue. B) a tubular gut with separate mouth and anus. C) a head. D) a coelom. E) a method of movement. Answer: C 47) The low energy demands of nematodes allow them to survive without a A) respiratory system. B) tubular gut. C) body cavity. D) reproductive system. E) skeleton. Answer: A 48) Within the mollusks, only the cephalopods have a A) radula. B) tubular gut. C) closed circulatory system. D) hinged shell. E) coelom. Answer: C

49) A hemocoel or blood cavity is found in or associated with A) sponges. B) acoelomates. C) an open circulatory system. D) all animals. E) cephalopods. Answer: C 50) The tube feet of echinoderms that are used for locomotion, capturing prey, and gas exchange are "inflated" by the , which is unique to the echinoderms. A) water-vascular system B) coelom C) hemocoel D) hydrostatic skeleton E) tubular gut Answer: A 51) A snail is a(n) A) mollusk. B) nematode. C) arthropod. D) chordate. E) echinoderm. Answer: A 52) A clam is a(n) A) echinoderm. B) mollusk. C) arthropod. D) chordate. E) arachnid. Answer: B 53) Spiders belong to the A) arthropods. B) chordates. C) echinoderms. D) cnidarians. E) mollusks. Answer: A 54) A crayfish is a member of the phylum A) Echinodermata. B) Mollusca. C) Annelida. D) Platyhelminthes. E) Arthropoda. Answer: E

55) Oysters are classified in thephylum A) Echinodermata. B) Mollusca. C) Annelida. D) Platyhelminthes. E) Arthropoda. Answer: B 56) A sea urchin is a member of the phylum A) Echinodermata. B) Mollusca. C) Annelida. D) Platyhelminthes. E) Arthropoda. Answer: A 57) Members of the phylum A) Echinodermata B) Mollusca C) Annelida D) Platyhelminthes E) Arthropoda

are characterized by having tube feet.

Answer: A 58) Which of the following phyla contains animals that reproduce asexually? A) Annelida B) Nematoda C) Cnidaria D) Chordata E) Mollusca Answer: C 59) In the various cnidarian species A) some live as polyps, some as medusae, and some as both in different stages. B) all have medusae as the juvenile stage and polyps as the adult stage. C) all have polyps as the juvenile stage and medusae as the adult stage. D) all live as polyps. E) all live as medusae. Answer: A 60) The venomous sea wasp is classified in the phylum A) Cnidaria. B) Arthropoda. C) Annelida. D) Mollusca. E) Nematoda. Answer: A

61) Parasitic tapeworms are members of the phylum A) Platyhelminthes. B) Annelida. C) Arthropoda. D) Nematoda. E) Cnidaria. Answer: A 62) An arthropod exoskeleton is composed of A) silica. B) lignan. C) calcium carbonate. D) cellulose. E) chitin. Answer: E 63) Charles Darwin wrote that members ofthe phylum they mix and aerate soil. A) Arthropoda B) Cnidaria C) Nematoda D) Annelida E) Platyhelminthes

are particularly important for agriculture because

Answer: D 64) The endoskeleton of an echinoderm is composed of A) cellulose. B) calcium carbonate. C) silica. D) lignan. E) chitin. Answer: B 65) Members of thetaxonomic group are best described as having a large, well-developed brain, having excellent vision, and being marine carnivorous predators. A) gastropods B) insects C) oligochaetes D) cephalopods E) bivalves Answer: D 66) Of all of the invertebrate phyla, only members of the phylum A) Cnidaria B) Annelida C) Nematoda D) Platyhelminthes E) Arthropoda Answer: E

can fly.

67) The leeches used by doctors to prevent blood clotting and stimulate the growth of blood vessels in patients recovering from reconstructive surgery are members of the phylum A) Arthropoda. B) Annelida. C) Nematoda. D) Cnidaria. E) Platyhelminthes. Answer: B 68) Animals obtain energy through photosynthesis. A) True B) False Answer: B 69) Animal cells lack a cell wall. A) True B) False Answer: A 70) An animal whose body cavity is completely lined with mesoderm has a pseudocoelom. A) True B) False Answer: B 71) Chordates and echinoderms are both protostomes. A) True B) False Answer: B 72) Most animal phyla are radially symmetrical. A) True B) False Answer: B 73) Sponges are radially symmetrical. A) True B) False Answer: B 74) Flatworms have a coelom that is only partially surrounded with mesoderm. A) True B) False Answer: B 75) The only invertebrates capable of flight are arachnids. A) True B) False Answer: B

76) Cephalopods are the only mollusks that have a closed circulatory system. A) True B) False Answer: A 77) A hemocoel is part of an open circulatory system. A) True B) False Answer: A 78) Sea stars (starfish) are bilaterally symmetrical at one time in their life cycle. A) True B) False Answer: A SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 79) Groups of similar cells that function together form

Answer: tissues 80) The

is the embryonic germ layer that develops into nervous tissue.

Answer: ectoderm 81) Animals that have distinct right and left sides display

symmetry.

Answer: bilateral 82) Animals that have no body cavity between the digestive system and the body wall are body plan.

in terms of

Answer: acoelomates 83) The are the simplest animals to have an excretory system. (Hint: This system consists of cilia beating within canals.) Answer: flatworms 84) The Trichinella worm, which causes trichinosis, is classified as a(n)

Answer: nematode 85) Flatworms that contain both male and female reproductive organs in the same individual are called Answer: hermaphroditic 86) A jointed exoskeleton is a characteristic of

Answer: arthropods 87) During insect complete metamorphosis, a larva forms a Answer: pupa 88) All animal cells lack a

Answer: cell wall

before becomingan adult.

89) If motility is considered a characteristic of animals, then why are stationary creatures such as sponges still considered to be animals? Answer: They have a larval stage that is motile, so they meet the criterion of mobility because at some point in their life cycle they are mobile. These animals become sessile as adults. 90) How does the skeletal system of an arachnid differ from that of a cephalopod? Answer: Arachnids have an exoskeleton composed of protein and chitin that surrounds the entire body. A cephalopod has a cartilage skeleton around its brains only. 91) How does the circulatory system of an annelid differ from the circulatory system of a gastropod? Answer: Annelids have a closed circulatory system, whereas gastropods have an open circulatory system. 92) If someone discovered a new compound that stops metamorphosis at the larval stage, what would be the benefits and drawbacks of this pesticide for humans? Answer: On the positive side, the organisms would not finish maturing and so could not reproduce, which would mean fewer insects. On the negative side, the larval stage is the "hungry stage," so the organisms would stay in the larval state and eat vast quantities, potentially destroying crops. 93) Explain why natural selection would have favored a closed circulatory system for cephalopods. Answer: A closed circulatory system distributes blood more efficiently, thus ensuring that all cells get an adequate supply of glucose and oxygen for ATP synthesis. Cephalopods are predatory creatures and rely on speed and stealth to catch their prey. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 94) The organism in the illustrationhas

A) a pseudocoelom. B) a true coelom. C) no coelom. Answer: A

95) The organism shown here isa(n)

A) fluke. B) arachnid. C) cephalopod. D) gastropod. E) annelid. Answer: C 96) Your job is to classify a newly discovered animal species. Your initial studies reveal that your specimen lacks tissues and organs and has no head, body symmetry, body cavity, or segmentation. To what phylum does this animal belong? A) Cnidaria B) Mollusca C) Annelida D) Platyhelminthes E) Porifera Answer: E 97) Your job is to classify a newly discovered animal species. Your initial studies reveal that your specimen has tissues but lacks organs; has no head, body cavity, or segmentation; and has radial symmetry. To what phylum does this animal belong? A) Cnidaria B) Mollusca C) Annelida D) Platyhelminthes E) Porifera Answer: A 98) Your job is to classify a newly discovered animal species. Your initial studies reveal that your specimen has tissues, organs, and a head; has no body cavity or segmentation; and has bilateral symmetry. To what phylum does this animal belong? A) Cnidaria B) Mollusca C) Annelida D) Platyhelminthes E) Porifera Answer: D

99) Your job is to classify a newly discovered animal species. Your initial studies reveal that your specimen has tissues, organs, a head, and a coelom; has no segmentation; and has bilateral symmetry. To what phylum does this animal belong? A) Cnidaria B) Mollusca C) Annelida D) Platyhelminthes E) Porifera Answer: B 100) Your job is to classify a newly discovered animal species. Your initial studies reveal that your specimen has tissues, organs, a head, and a pseudocoelom; has no segmentation; and has bilateral symmetry. To what phylum does this animal belong? A) Nematoda B) Platyhelminthes C) Cnidaria D) Mollusca E) Annelida Answer: A 101) Your job is to classify a newly discovered animal species. Your initial studies reveal that your specimen has tissues, organs, and a coelom; has no head or segmentation; and has radial symmetry. To what phylum does this animal belong? A) Nematoda B) Platyhelminthes C) Mollusca D) Echinodermata E) Cnidaria Answer: D

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) The discovery of a coelacanth in South Africa in 1938 was surprising to biologists because it A) has not evolved for more than 80 million years. B) is the first species to have made the transition to land. C) was thought to be extinct. D) represents a transition between two major groups of fishes. E) was a newly evolved species. Answer: C 2) All chordates have A) a ventral, hollow nerve cord. B) a backbone. C) a post-anal tail. D) gills. E) a bonyendoskeleton. Answer: C 3) Which of the following is present in all chordates? A) Chloroplasts B) A vertebral column C) A notochord D) An external skeleton E) Four limbs Answer: C 4) How does the nerve cord of chordates differ from the nerve cord of animals in other taxonomic groups? A) It develops from thegill slits. B) It runs along the dorsal side of the body. C) It does not extend into the tail. D) It does not develop until after the embryonic period. E) It is surrounded by bone. Answer: B 5) At some stage of the life cycle, all chordates have A) a backbone. B) a pre-anal tail. C) a ventral nerve cord. D) an externalskeleton. E) pharyngeal gillslits. Answer: E 6) In all chordates, the notochord A) may or may not appear at all; it is not found in all chordates. B) appears at least during early stages of development. C) is found throughout the lifecycle. D) appears only in adults. E) appears only during early stages ofdevelopment. Answer: B

7) The notochord A) becomes the digestive system. B) becomes the brain. C) is for muscle attachment. D) develops from the pharyngeal gill slits. E) forms the nerve cord in an adult. Answer: C 8) Which of the following has a ventral nerve cord? A) Shark B) Earthworm C) Frog D) Coelacanth E) Hummingbird Answer: B 9)

have a dorsal nerve cord. A) Bugs B) Leeches C) Sharks D) Starfishes E) Earthworms Answer: C

10) Which of the following features is absent in lancelets? A) Nerve cord B) Gill slits C) Notochord D) Backbone E) Tail Answer: D 11) Lancelets live in A) the sea. B) fresh water. C) treetops. D) sulfur springs. E) deserts. Answer: A 12) Which of the following best describes which chordate characteristics lancelets retain as adults? A) Pharyngeal gill slits, limbs, and lobed fins B) Dorsal nerve cord, jaws, limbs, and lobed fins C) Notochord, dorsal nerve cord, post-anal tail, and pharyngeal gill slits D) Post-anal tail, hair, jaws, and amniotic egg E) Notochord, lobed fins, and jaws Answer: C

13) A tunicate is a(n) A) jawless fish. B) bony fish. C) amphibian. D) invertebrate chordate. E) cartilaginous fish. Answer: D 14) Larval sea squirts A) live in fresh water. B) display all four chordate characteristics. C) have a brain encased inbone. D) are sessile. E) lack a notochord. Answer: B 15) The great size and mobility of the vertebrates are likely the result of A) lightweight endoskeletons. B) four-chambered hearts. C) lungs used for respiration. D) increased brain size and complexity. E) uterine development ofoffspring. Answer: A 16) What characteristic of hagfishes differentiates them from lancelets and tunicates? A) Bony jaws B) Dorsal nerve cord C) Skull surrounding the brain D) Post-anal tail E) Gills Answer: C 17) In vertebrates, the analogous structure to the notochord is A) a nerve cord. B) jaws. C) fins. D) a skull. E) a backbone. Answer: E 18) Which characteristic differentiates hagfishes from other craniates? A) Bony jaws B) Skeletal elements surrounding the nerve cord C) A lack of gills D) Two-chambered hearts E) Lobe-like fins Answer: B

19) What is the function of the vertebral column? A) Protect the nerve cord B) Tear and crush food C) Help increase the metabolic rate D) Provide weight in aquatic life-forms E) Limit muscle attachments Answer: A 20) The earliest vertebrates lacked A) skeletons. B) gills. C) brains. D) a notochord. E) jaws. Answer: E 21) What is the advantage of paired appendages? A) They protect the nerve cord. B) They provide internal support for the animal. C) They improve mobility. D) They improve the sensory ability. E) They increase the metabolic rate, making animals endothermic. Answer: C 22) Parasitic lampreys have A) internal fertilization. B) a three-chambered heart. C) sucker-like mouths lined with teeth. D) bony jaws. E) radial proportions. Answer: C 23) Why are lampreys classified asvertebrates? A) They lack gills. B) They lack jaws. C) They are ectothermic. D) Their nerve cord is surrounded by cartilage. E) They have an exoskeleton. Answer: D 24) A lamprey is a(n) A) cartilaginous fish. B) jawless fish. C) invertebrate chordate. D) amphibian. E) bony fish. Answer: B

25) Lamprey populations introduced into the Great Lakes have grown dramatically. Why? A) A fish species that they naturally prey upon has recently been introduced into the Great Lakes. B) They have no natural predators in these waters. C) Competitive species have driven them from the ocean. D) Lamprey stocking programs have been highly effective. E) Fishers have intentionally introduced them with the hope of farming them for "eel skin." Answer: B 26) Lampreys have reduced the size of commercial fish populations in the Great Lakes because they A) share many of the samepredators. B) are predators to many of the same prey species. C) compete for food with those fish species. D) are parasites on those fishspecies. E) secrete toxins that injure or kill other fishes. Answer: D 27) Lampreys differ from other vertebrates because they lack A) skulls. B) hearts. C) gills. D) metabolism. E) jaws. Answer: E 28) Cartilaginous fishes differ from lampreys because they A) are ectotherms. B) lack a skull. C) have jaws. D) have a three-chambered heart. E) lack a skeleton. Answer: C 29) The skeletons of rays and skates are made of A) cartilage. B) bone. C) muscle. D) chitin. E) protein slime. Answer: A 30) Chondrichthyes includes A) lampreys. B) all fishes. C) sharks. D) frogs. E) whales. Answer: C

31) Which vertebrate group is the most diverse? A) Actinopterygii B) Reptilia C) Mammalia D) Actinistia E) Chondrichthyes Answer: A 32) Most have swim bladders. A) ray-finned fishes B) marine mammals C) jawless fishes D) cartilaginous fishes E) lobe-finned fishes Answer: A 33) Why have populations of many ray-finned fish species decreased in recent years? A) Overfishing by humans B) Bacterial disease C) Pollution of their environment D) Parasitism by lampreys E) Loss of their prey species Answer: A 34) Lungfishes are classified as A) ray-finned fishes. B) jawless fishes. C) lobe-finned fishes. D) amphibians. E) cartilaginous fishes. Answer: C 35) A shark is a(n) A) bony fish. B) amphibian. C) jawless fish. D) cartilaginous fish. E) invertebrate chordate. Answer: D 36) The characteristic that separates cartilaginous fishes from lampreys is A) lungs supplemented by air sacs. B) bony skeletons. C) sucker-like mouths lined with teeth. D) jaws. E) four-chambered hearts. Answer: D

37) A(n) protects the internal organs of ray-finned fishes. A) internal cartilageskeleton B) exoskeleton made of cartilage C) internal bony skeleton D) notochord E) exoskeleton made of chitin Answer: C 38) Fins composed of a web of skin covering thin, bony spines are characteristic of A) lampreys. B) hagfishes. C) cartilaginous fishes. D) lobe-finned fishes. E) ray-finned fishes. Answer: E 39) Fins composed of rod-shaped bones surrounded by thick layers of muscle are characteristic of A) lampreys. B) lobe-finned fishes. C) hagfishes. D) ray-finned fishes. E) cartilaginous fishes. Answer: B 40) Which were the first tetrapods to move to land? A) Hagfishes B) Ray-finned fishes C) Reptiles D) Amphibians E) Monotremes Answer: D 41) Why do amphibians need a moist environment? A) Amphibians eat only aquatic organisms. B) Amphibians require a moist environment to support their body weight because their cartilaginous skeleton is weak. C) Their eggs have only a jelly-like coating that needs to stay moist. D) Amphibians require a moist environment for their scales to develop. E) The gills of the adult won't work if they dry out. Answer: C 42) One adaptation that enables an animal to live successfully on dry land is A) moist skin used for gasexchange. B) external fertilization. C) a two-chambered heart. D) development in a shelled egg. E) gills. Answer: D

43) Amphibians are not especially successful land-dwellers because of their A) production of a shelled amniotic egg. B) lungs that are supplemented by air sacs. C) two-chambered hearts. D) choice of prey. E) reliance on moist skin for gas exchange. Answer: E 44) A tadpole isa(n) A) bony fish. B) cartilaginous fish. C) invertebrate chordate. D) jawless fish. E) amphibian. Answer: E 45) Which vertebrate group has a three-chambered heart? A) Ray-finned fishes B) Lobe-finned fishes C) Amphibians D) Birds E) Mammals Answer: C 46) Which of the following best describes the major problem(s) amphibians face? A) Habitat destruction, global warming, and X-ray exposure B) A major decrease in populations due to a variety of factors, including toxins, UV exposure, fungal infections, and habitat destruction C) Exposure to environmental toxins, global warming, and ozone depletion D) Developmental abnormalities from UV light exposure and ozone depletion E) Fungal infection, bacterial infection, and prion infection Answer: B 47) Why can't amphibians be entirelyterrestrial? A) They have a three-chambered heart that is not efficient enough for terrestrial life. B) Their limbs are not adapted to support their bodies on land. C) Their reproduction requires water to allow fertilization and keep eggs moist. D) Their digestion is adapted for consuming aquatic prey. E) They do not have lungs but instead have gills that require water for gas exchange. Answer: C 48) Why have reptiles successfully adapted to land? A) They have a two-chambered heart to maximize oxygen utilization. B) They lack gills at any point during their development. C) They produce eggs that resistdehydration. D) They nurse their young. E) They are endothermic. Answer: C

49) To prevent dehydration, reptiles have A) moist, slime-coveredskin. B) eggs that contain no water. C) a four-chambered heart. D) scaly skin. E) embryos that lack gills. Answer: D 50) Why don't reptilian embryos dry out in a desert habitat? A) Reptile eggs are protected by a jelly-like coating. B) The placenta facilitates gas exchange between the mother and the embryo. C) Reptiles are endothermic. D) Reptiles produce shelled amniotic eggs. E) Reptiles produce lots of defensive slime. Answer: D 51) The high body temperature of birds and mammals is due to A) behaviors such as basking in the sun and seeking shade. B) the presence of sweat, scent, and sebaceous glands. C) the exchange of gases and nutrients via the placenta. D) the fur that insulates them. E) their high metabolic rates. Answer: E 52) Which of the following is essential for birds to maintain their high metabolic rate? A) Skin that is used as a respiratory structure B) A four-chambered heart, which maximizes oxygen delivery C) Hollow bones, which decrease bodymass D) Extraordinary coordination by a well-developed nervous system E) Embryonic development in a shelled amniotic egg Answer: B 53) Why are reptiles better adapted to land dwelling than amphibians are? A) Their two-chambered heart better mixes oxygenated and deoxygenated blood. B) Their scaly skin prevents waterloss. C) Their moist skin is used as a respiratory structure. D) Their embryos develop in auterus. E) Their lungs have a smaller surface area for gas exchange. Answer: B 54) A marsupial is a(n) A) mammal. B) amphibian. C) bird. D) reptile. E) mollusk. Answer: A

55) An animal that has a four-chambered heart, is endothermic, and does not give birth to live offspring can be classified as a(n) A) amphibian. B) reptile. C) mollusk. D) mammal. E) bird. Answer: E 56) A terrestrial vertebrate that has scales and a three-chambered heart is a(n) A) amphibian. B) reptile. C) lobe-finned fish. D) mammal. E) bird. Answer: B 57) Which of the following is TRUE of all reptiles? A) They are exclusively terrestrial. B) They have four well-developed limbs. C) They have teeth. D) They are predatory carnivores. E) They have a heart with either three or four chambers. Answer: E 58) Birds belong to a related group of vertebrates that includes all of the A) reptiles. B) amphibians. C) ray-finned fishes. D) mammals. E) lobe-finned fishes. Answer: A 59) Which characteristic do birds share with mammals? A) A single ovary in females B) Hollow bones C) Mammary glands D) A four-chambered heart E) Sweat glands Answer: D 60) Although they are mammals, monotremes lack A) a four-chambered heart. B) nipples. C) mammary glands. D) ovaries in females. E) hair. Answer: B

61) How do monotremes differ from other mammals? A) They do not produce milk. B) They have a four-chambered heart. C) They have claws. D) They lay eggs. E) They have hair. Answer: D 62)

are the mammals with the greatest number of species. A) Bats B) Whales C) Marsupials D) Rodents E) Primates Answer: D

63) All chordates have pharyngeal gill slits at some point during their development. A) True B) False Answer: A 64) Animals that have a ventral nerve cord during embryonic development are classified as chordates. A) True B) False Answer: B 65) During embryonic development, the tail in mammals extends past the anus. A) True B) False Answer: A 66) The notochord persists into adulthood in all chordates. A) True B) False Answer: B 67) Craniates have skulls made of either bone or cartilage. A) True B) False Answer: A 68) Hagfishes lack jaws. A) True B) False Answer: A 69) Hagfishes have three-chambered hearts, which improve gas exchange with the lungs. A) True B) False Answer: B

70) An animal without a vertebral column has an unprotected notochord. A) True B) False Answer: B 71) Lampreys are endothermic. A) True B) False Answer: B 72) Skates and other cartilaginous fishes lack jaws. A) True B) False Answer: B 73) Cartilaginous fishes lack gills in their adult form. A) True B) False Answer: B 74) Cartilaginous fishes have internal fertilization. A) True B) False Answer: A 75) The skeletons of ray-finned fishes are made of cartilage. A) True B) False Answer: B 76) The fins of the coelacanth have rod-shaped bones and thick muscles. A) True B) False Answer: A 77) Salamanders are the only vertebrate capable of regenerating lost limbs. A) True B) False Answer: A 78) The amnion creates an aquatic environment for developing embryos. A) True B) False Answer: A 79) To limit water loss in dry environments, reptiles breathe through their skin. A) True B) False Answer: B

80) The shelled egg of reptiles prevents the egg from dehydrating. A) True B) False Answer: A 81) Birds are feathered reptiles. A) True B) False Answer: A 82) The bones of birds are heavier than the bones of other reptiles to support the stresses of flight. A) True B) False Answer: B 83) Endothermic animals have four-chambered hearts. A) True B) False Answer: A 84) All female mammals produce milk to feed their young. A) True B) False Answer: A 85) The placenta in mammals is responsible for gas exchange for the embryo. A) True B) False Answer: A 86) Marsupials are egg-laying mammals. A) True B) False Answer: B 87) Mammals have the most complex nervous system of all vertebrates. A) True B) False Answer: A SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 88) During embryonic development, all chordates have a

nerve cord.

Answer: dorsal 89) The is a stiff, flexible rod that, at some point during the development of all chordates, extends along the length of the body, sandwiched between the digestive tract and the nerve cord. Answer: notochord

90) Lancelets, tunicates, and craniates are all classified as

Answer: chordates 91) All chordates that have a skull made of either bone or cartilage surrounding the brain are classified as Answer: craniates 92) Adult tunicates have lost two embryonic features: the tail and the

Answer: notochord 93) The

are craniates that lack a vertebral column.

Answer: hagfishes 94) Hagfishes and lampreys differ from other fishes because they lack

Answer: jaws 95) In sharks and rays, the skeleton is made of

Answer: cartilage 96) The

is the internal membrane of the shelled eggs of reptiles.

Answer: amnion 97) The

are aquatic reptiles that lack a shell.

Answer: crocodilians 98) Mammals have a

heart.

Answer: four-chambered 99) The embryo.

forms from embryonic and uterine tissues and is the site of exchange between mother and

Answer: placenta 100) Nearly all marsupials are found in

Answer: Australia 101)

are mammals that layeggs. Answer: Monotremes

102) A turtle is classified as a(n)

Answer: reptile 103) What characteristics must an animal possess in order to be considered a chordate? Answer: At some point during their lives, all chordates have a dorsal nerve cord, a notochord, pharyngeal gill slits, and a post-anal tail. 104) Even though humans don't have tails or gills, they are still chordates; why is this so? Answer: During development, human embryos have both gill slits and a post-anal tail. Even though these characteristics are lost in adults, because they existed at one point during development, humans are classified as chordates.

105) How do hagfishes differ from lobe-finned fishes and cartilaginous fishes? Answer: Hagfishes lack both jaws and bone around the nerve cord. 106) What survival advantage do jawed fishes have over jawless fishes? Answer: Jawed fishes are able to eat a wider variety of foods, which gives them a survival advantage. 107) A swamp contains lungfishes, lampreys, and ray-finned fishes. As the swamp begins to dry out, which fishes will better survive and why? Answer: Lungfishes have both gills for breathing underwater and lungs for breathing in air. Neither lampreys nor ray-finned fishes can breathe the air. The lungfishes will be able to survive for short periods of time out of the water. 108) Why do amphibians need to live in moist habitats? Answer: Amphibians need a moist environment for their eggs to survive and to keep their skin moist to assist in respiration. 109) What characteristics allowed reptiles to become completely terrestrial? Answer: Reptiles evolved scaly skin that resists dehydration, internal fertilization so that the male sperm can swim through the female's body to reach the eggs, and amniotic eggs with shells that protect the egg from dehydration. 110) Why are birds classified asreptiles? Answer: Birds and reptiles both lay shelled eggs. The feathers of birds are modified reptilian body scales, but they retain scales on their legs. 111) What characteristics differentiate monotremes from other mammals? Answer: Monotremes lay shelled eggs rather than developing embryos in a uterus like other mammals. Also, monotremes produce milk like other mammals but lack nipples for delivering the milk to their young. 112) How does marsupial reproduction differ from the reproduction of placental mammals? Answer: In marsupials, the young develop in the uterus for only a short time and are born while still very immature. Most finish their development in a pouch. In placental mammals, the young complete their embryonic development within the uterus before they are born.

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 113) This animal has

A) a cartilage skeleton. B) a pre-anal tail. C) bony spines within its fins. D) placental development. E) hard-shelled eggs. Answer: A

114) This animal is classified asa

A) lobe-finned fish. B) lamprey. C) tunicate. D) monotreme. E) ray-finned fish. Answer: E

115) What characteristics place these animals in the same group?

A) Internal fertilization, cartilaginous skeletons, and four-chambered hearts B) Ventral nerve cords and gills in their adult forms C) Shelled eggs, four-chambered hearts, and being endothermic D) Moist skin, eggs with a jelly-like coating, lungs in their adult forms, and gas exchange through their skin E) Cartilaginous skeletons, placental development, and internal fertilization Answer: D

116) This animal is a

A) marsupial. B) tunicate. C) monotreme. D) placental mammal. E) reptile. Answer: C 117) On a remote island, a new animal is found. It has a four-chambered heart and lungs and is endothermic. It has internal fertilization, lays shelled eggs, and nurses its young after they hatch. This animal is most likely a(n) A) amphibian. B) marsupial. C) coelacanth. D) reptile. E) monotreme. Answer: E 118) You find a new animal. It is a large, predatory marine vertebrate covered with scales. It has a two-chambered heart and gills, and its skeleton is made of cartilage. You should classify it as A) Actinistia. B) Reptilia. C) Actinopterygii. D) Chondrichthyes. E) Amphibia. Answer: D

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) If you teach your dog to sit by giving him a treat for every correct response, this is an example of A) social learning. B) operant conditioning. C) innate behavior. D) habituation. E) insight learning. Answer: B 2) After eating at the new restaurant in town, you develop a mild case of food poisoning. Consequently, you never go back to that restaurant again. This is an example of A) trial-and-error learning. B) habituation. C) innate behavior. D) classical conditioning. E) insight learning. Answer: A 3) Nesting geese will roll softballs (placed next to their nests by biologists) into their nests, perhaps because the balls resemble eggs that might have rolled out of the nest. This behavior is most likely A) insight learning. B) trial-and-error learning. C) conditioned. D) innate. E) habituation. Answer: D 4) A behavior that occurs immediately after birth, before any encounter with another member of the same species, is A) learned. B) not under genetic control. C) nonadaptive. D) based on habituation. E) innate. Answer: E 5) A toad avoiding bad-tasting insects is an example of a(n) A) learned behavior. B) random behavior. C) innate behavior. D) instinctive behavior. Answer: A 6) A strong association learned during a sensitive period of an animal's development is referred to as A) habituation. B) imprinting. C) insight learning. D) classical conditioning. E) altruism. Answer: B

7) Baby ducks can be taught to behave as though a human investigator was their mother by providing the appropriate stimulus during a sensitive period. This form of learning is called A) classical conditioning. B) altruism. C) habituation. D) fixed action behavior. E) imprinting. Answer: E 8) The protist Stentor contracts when it is touched for the first time but gradually stops retracting if the touching is continued. This behavior is called A) insight learning. B) operant conditioning. C) imprinting. D) habituation. E) a sensitive period. Answer: D 9) B. F. Skinner is most closely associated with A) causing chickens to return to the roost at night. B) operant conditioning (trial-and-error learning). C) imprinting experiments with ducks. D) breeding experiments withpigeons. E) insight learning. Answer: B 10) Ivan Pavlov is most closely associated with A) breeding experiments with pigeons. B) classical conditioning with dogs. C) operant conditioning (trial-and-error learning). D) imprinting experiments with ducks. E) insight learning. Answer: B 11) During operant conditioning, an animal learns to A) change an imprinted behavior. B) perform a behavior to receive a reward or avoid punishment. C) imprint upon an inappropriate object. D) perform a response to a new stimulus. E) behave like a different animal. Answer: B 12) Failure to respond to harmless, repetitive stimulation is an example of A) operant conditioning. B) insight learning. C) habituation. D) trial-and-error learning. E) imprinting. Answer: C

13) A newly hatched duck adopts the most frequently encountered animal or object it sees during a sensitive period as its mother. This is an example of A) operant conditioning. B) insight learning. C) habituation. D) trial-and-error learning. E) imprinting. Answer: E 14) Training an animal to respond in a specific way to a stimulus is called A) operant conditioning. B) insight learning. C) habituation. D) trial-and-error learning. E) imprinting. Answer: A 15) When city dwellers fail to respond to ordinary traffic sounds, it is an example of A) operant conditioning. B) insight learning. C) habituation. D) trial-and-error learning. E) imprinting. Answer: C 16) A child learns which foods taste good or bad through A) habituation. B) insight learning. C) innate learning. D) imprinting. E) trial-and-error learning. Answer: E 17) If a baby squirrel is adopted by a mother cat and begins to copy the behaviors of the cat, it is an example of A) insight learning. B) operant conditioning. C) trial-and-error learning. D) habituation. E) imprinting. Answer: E 18) Which type of learning would be most beneficial for a person from New York City who is shipwrecked on an uninhabited tropical island? A) Imprinting B) Innate learning C) Habituation D) Insight learning E) Operant conditioning Answer: D

19) When walking your male dog, you notice that he urinates on every vertical object in his path. His urine is used to "mark" his territory and serves as a chemical signal to other dogs. What does the urine contain? A) Releasers B) Hormones C) Pheromones D) Apomones Answer: C 20) Which communication method is most effective over short distances? A) Touch B) Pheromones C) Visual communication D) Vocalizations E) Dominance hierarchies Answer: C 21) To communicate across hundreds of miles, whales use A) sound. B) touch. C) sight. D) pheromones. E) wave motions. Answer: A 22) The different calls of vervet monkeys indicate A) the types of food available. B) the size of a territory. C) the types of predators detected. D) the availability of water. E) sexual differences. Answer: C 23) The greatest long-distance sound communication occurs among A) whales. B) bats. C) insects. D) elephants. E) birds. Answer: A 24) The shape, size, or color of an animal A) relates to the pheromones the animal produces. B) does not communicate information. C) is used to mark the boundaries of territories. D) plays a role in active visual communication. E) plays a role in passive visual communication. Answer: E

25) Chemicals produced by an individual that influence the behavior of members of the same species are called A) enzymes. B) hormones. C) pheromones. D) stimuli. E) steroids. Answer: C 26) Which of these is an example of a pheromone? A) Light emitted by fireflies B) A dog urinating on abush C) Bird song D) A peacock's tail E) The waggle dance of the honeybee Answer: B 27) A chemical produced by one animal that is usually only detectable by another animal of the same species is called a A) neurotransmitter. B) releaser. C) hormone. D) pheromone. E) subliminal suggestion. Answer: D 28) A bird flashing white patches underneath its wings is an example of what type of communication? A) Chemical B) Active visual C) Sound D) Passive visual E) Physical contact Answer: B 29) Two cats getting ready to fight puff up their fur to make themselves look larger. This is an example of A) aggressive behavior. B) pheromones. C) altruism. D) imprinting. E) minimized competition. Answer: A 30) What is the function of the dominance hierarchy within a group of animals? A) Eliminate competition B) Increase fighting among members of a population C) Minimize aggression D) Limit the size of thepopulation E) Increase competition Answer: C

31) Aggressive encounters between individuals of the same species A) are always a fight to the death. B) usually result in one of the individuals being injured. C) do not occur in nature. D) occur only when food supplies are low. E) usually include rituals or displays. Answer: E 32) Defense of an area that contains important resources for survival is termed A) aggression. B) kinesis. C) territoriality. D) appeasement. E) passive behavior. Answer: C 33) The dominant animal in a social hierarchy, such as a wolf pack, is called the A) leader. B) omega. C) king. D) alpha. E) master. Answer: D 34) An animal that effects changes to make itself look larger is exhibiting A) a submissive posture. B) dominance in a social group. C) a readiness to mate. D) a desire to fight. E) an aggressive display. Answer: E 35) When threatened, a cobra will rear up and spread its hood, which makes its head look larger and displays the eye spots. What kind of behavior is this? A) A desire to fight B) A submissive posture C) A readiness to mate D) An aggressive display E) Dominance in a social group Answer: D 36) Female peafowl (peahens) prefer to breed with males (peacocks) that have the longest tails. However, the longer the peacock's tail, the less well he can fly and the more likely he is to be eaten by predators. Which of the following statements is TRUE? A) Both sexual selection and natural selection favor shorter tails in peacocks. B) Sexual selection favors shorter tails, but natural selection favors longer tails. C) Sexual selection favors longer tails, but natural selection favors shorter tails. D) Both sexual selection and natural selection favor longer tails in peacocks. Answer: C

37) Male bullfrogs produce loud calls during the mating season to attract females. The loudest males tend to mate with the most females. What can we reasonably conclude about this situation? A) The louder a male's call, the lower his quality. B) We cannot come to any conclusions based on the information given. C) The louder a male's call, the higher his quality. D) The loudness of a male's call is not a good predictor of his quality. Answer: C 38) How do silk moths attract mates? A) The males turn bright red as a visual signal. B) The males sing a high-pitched song to attract the females. C) The females secrete pheromones to attract males. D) The females flit around the males in an elaborate dance. E) They build elaborate nests. Answer: C 39) Bowerbirds build elaborate nests to A) hide from predators. B) attract prey. C) attract a mate. D) defend their territory. E) increase aggressive behavior. Answer: C 40) What is the advantage ofplay? A) Play decreases competition within the group. B) Play decreases the risk of injury to the young. C) Play slows the development of adult behaviors. D) Play is a chance to practice skills such as hunting, fleeing, and social behaviors. E) Play keeps the young close to the parents for longer. Answer: D 41) Which of the following is a disadvantage for animals living in groups? A) Increased chance of being spotted by predators B) Lower efficiency in finding food C) Reduced chance of finding amate D) Decreased risk of disease Answer: A 42) Complex societies involving a caste system, where individuals are born into a specific role, can be found among which of the following? A) Fishes B) Reptiles C) Birds D) Insects E) Amphibians Answer: D

43) Foraging honeybees communicate the location of a source of food by A) creating noises with their wings. B) flying around the location. C) using a unique verbal language. D) releasing pheromones. E) doing a specific waggle dance. Answer: E 44) When the back of a male stickleback turns blue, this signal is perceived by females A) to delimit territory. B) to signal the beginning of the mating season. C) as an example of courtship behavior. D) to describe the location offood. E) to indicate danger to the school. Answer: C 45) Honeybees will sting a bear that is robbing their hive even though the bees will die after they sting the bear. This is an exampleof A) altruism. B) submission. C) habituation. D) conditioning. Answer: A 46) Worker honeybees are A) sterile males. B) immature bees of either sex. C) fertile males. D) sterile females. E) fertile females. Answer: D 47) Among social animals, cooperative behavior does NOT usually include A) increased likelihood of finding mates. B) everybody doing their own thing. C) a caste system in which individuals do certain jobs. D) alliances among members of thepopulation. E) division of labor. Answer: B 48) Which of the following illustrates altruism? A) Parent birds spend much of their time and energy feeding their young. B) A mother bird pretends to be wounded to distract a predator away from her young. C) Males sing to attract females as mating partners. D) Parent birds clean out theirnests. E) Birds of a different species care for a cuckoo egg. Answer: B

49) Kin selection refers to A) deciding which related animals can live in the colony. B) an animal promoting the survival of the genes of its close relatives. C) determining which related animals must live and which must die. D) deciding which related animals can share the food. E) the selection of a mate. Answer: B 50) Drones are male honeybees that A) build the hexagonal cells of wax for the larvae. B) feed the developing larvae. C) mate with the queens. D) forage for food. Answer: C 51) Smiling when happy seems to be an expression common to all human societies, suggesting that this behavior is probably A) based on social standing. B) learned. C) altruistic. D) genetic in origin. Answer: D 52) When a 1-month-old baby is shown a piece of white paper with two dark, eye-sized spots, the baby will A) smile. B) exhibit avoidance actions. C) exhibit fright. D) vomit. E) not respond to a stimulus of thisnature. Answer: A 53) Human facial expressions in response to various emotions A) vary according to age. B) vary according to sex. C) are remarkably similar among different cultures. D) vary tremendously from culture to culture. E) vary according torace. Answer: C 54) A hungry newborn human infant, touched on the side of her mouth, will turn her head and attempt to suckle. This behavior is A) not under genetic control. B) learned. C) innate. D) nonadaptive. Answer: C 55) An animal can imprint only on members of its own species. A) True B) False Answer: B 9

56) A learned behavior cannot be changed. A) True B) False Answer: B 57) Behaviors result from an interaction between genes and environment. A) True B) False Answer: A 58) Trial-and-error learning can be important in the development of a behavior. A) True B) False Answer: A 59) Migration is an innate behavior among whooping cranes. A) True B) False Answer: A 60) Pheromones have the ability to modify reproductive behaviors in some animals. A) True B) False Answer: A 61) Pheromones affect only the animal that produces them. A) True B) False Answer: B 62) Birds produce species-specific songs. A) True B) False Answer: A 63) The pattern of flashes produced by fireflies is an example of visual communication. A) True B) False Answer: A 64) The effectiveness of sound for communication is limited because only simple messages can be transmitted. A) True B) False Answer: B 65) Only primates have the ability to communicate by sound. A) True B) False Answer: B

66) Pheromones are species specific. A) True B) False Answer: A 67) The fur standing up along a dog's back when it confronts a strange dog is an example of visual communication. A) True B) False Answer: A 68) Dominance hierarchies minimize aggression in social animals. A) True B) False Answer: A 69) Territoriality increases aggression. A) True B) False Answer: B 70) In male bighorn sheep, the dominant male is usually the one with the largest horns. A) True B) False Answer: A 71) Successful defense of territories increases the odds of mating success. A) True B) False Answer: A 72) Birds use vocal displays to defend their territories. A) True B) False Answer: A 73) The head bobbing of lizards is a visual mating signal. A) True B) False Answer: A 74) A female dog in estrus attracts males with pheromones. A) True B) False Answer: A 75) Only primates play. A) True B) False Answer: B

76) Play inhibits normal behavioral development. A) True B) False Answer: B 77) Living in a social group decreases the odds of finding a mate. A) True B) False Answer: B 78) Living in a social group increases the risk of contracting an infectious disease. A) True B) False Answer: A 79) The function of honeybee queens is to bring nectar back to the hive. A) True B) False Answer: B 80) The queen in a naked mole rat colony is the only female allowed to breed. A) True B) False Answer: A 81) Suckling is an innate behavior in mammals. A) True B) False Answer: A SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 82) Human babies are born with a sucking reflex. This is an example of a(n)

behavior.

Answer: innate 83) A child touches a hot pot on a stove, burns his finger, and won't touch another pot. This is an example of learning. Answer: trial-and-error 84) When you first move to a city, you can hardly sleep because of the nighttime traffic noise. Within a week, you don't notice it at all. This is an example of . Answer: habituation 85) A newly hatched duck adopts the first large, moving object it sees as its mother. This is an example of Answer: imprinting 86) Animals use problem.

learning when they figure out how to solve a problem without prior experience with that

Answer: insight

87) Someone who lives next to a bell tower doesn't even notice the chiming of the bells after a while. This is an example of . Answer: habituation 88) A toad that eats a bee and is stung tends to avoid eating bees afterward. This is an example of learning. Answer: trial-and-error 89) The ability to make changes in behavior based on experience is called

Answer: learning 90) A dog growling is an example of

communication.

Answer: sound 91) A cat grooming another cat is an example of

communication.

Answer: touch 92) Social bonds between members of a group can be developed by

communication.

Answer: touch -based communication.

93) A lion spraying urine on a tree is an example of Answer: chemical (or pheromone) 94) In a wolf pack, the alpha is the

animal.

Answer: dominant 95) All members of a wolf pack help to raise the pups-sharing food, defending the pups, teaching them to hunt-even though this behavior decreases the mating potential of a given pack member. This behavior is called . Answer: altruism 96) Worker bees are rendered sterile because of

Answer: queen substance (or queen pheromones) 97) In human infants, smiling is a(n)

behavior.

Answer: innate 98) What is operant conditioning? Answer: Operant conditioning is the process by which animals learn to perform a behavior to receive a reward or avoid punishment. Operant conditioning is also known as trial-and-error learning. 99) What is insight learning? Answer: In insight learning, an animal solves a novel problem suddenly, without having experienced it before. 100) How does operant conditioning differ from insight learning? Answer: Operant conditioning is based on prior experience with rewards or punishments in a given situation. Insight learning does not require prior experience with the situation.

101) What methods do animals use to communicate with one another? Answer: Animals communicate using sound, touch, visual signals, and chemical signals. 102) What advantage does sound communication have over visual communication? Answer: Sound signals can be transmitted over longer distances and even through physical barriers. 103) What disadvantage does sound communicationhave? Answer: Sounds may attract predators and signal the location of the animal making the sound. 104) How do animals identify theirterritories? Answer: Animals use aggressive behaviors, vocalizations, and pheromones to identify territories. 105) What are the benefits ofterritoriality? Answer: Territoriality decreases aggression within a population, reducing the risk of actual combat between animals. 106) Briefly explain how play behavior might have survival value and thus be affected by natural selection. Answer: Playful behaviors provide a chance for juvenile animals to practice behaviors that will be important later in life. For example, the play behaviors of many different species of mammals are similar to the hunting and escaping behaviors of adults. If play behavior has a genetic (innate) component, then natural selection is expected to favor individuals that play as juveniles. 107) What are the advantages to being a social animal? Answer: Social animals work as a group, which makes it easier for them to detect and repel predators, improves their likelihood of finding a mate, improves hunting efficiency, and allows for division of labor. 108) What are the disadvantages to being a social animal? Answer: Living in groups increases competition within the group for resources, increases the risk to offspring from other members of the group, increases the risk of infection from contagious diseases, and increases the risk of being spotted by predators.

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 109) The insects in the photographare demonstrating

communication.

A) visual B) sound C) touch D) vocal E) chemical Answer: E

110) Wolves are social animals that behave and communicate with each other through a variety of body movements. If a wolf who is initially aggressive as he moves through the pack encounters a more dominant individual, his behavior shifts. Which of the postures shown does he assume?

A) Figure a B) Figure b C) Both Figures a and b D) Neither Figure a norb Answer: B 111) Normal fruit fly larvae move away from their food after eating. However, some larvae that were subjected to X-rays remain near or in their food after eating. There is a consistent difference in the DNA of these two types of larvae. What can we conclude about this behavior? A) Nothing can be concluded about this behavior from the information provided. B) It has a clear genetic component. C) It appears to be entirelylearned. D) It is an innate behavior. Answer: B

112) In a classic experiment from the 1930s, a biologist conducted selective breeding experiments involving maze-running behavior in rats. He repeatedly bred together males and females that made the fewest mistakes, and he also bred together males and females that made the most mistakes. After eight generations, all mice that descended from "maze-smart" parents were better at running the maze than all mice that descended from "mazedumb" parents. This study indicatesthat A) maze running is a purely innate behavior in rats. B) trial-and-error learning in rats appears to have a genetic component. C) rats move through a maze randomly. D) maze running is a purely learned behavior. E) nothing can be concluded about maze-running behavior inrats. Answer: B 113) Some insects that have an unpleasant taste, such as monarch butterflies, have bright, high-contrast color patterns. Most predators, once they have tasted a monarch, will leave all other monarchs alone in the future. What type of learning has occurred in the predators? A) Altruism B) Insight learning C) Operant conditioning D) Habituation E) Imprinting Answer: C 114) At the start of the breeding season, male stickleback fish undergo a number of significant changes. Their bellies become bright red and they become aggressive toward other males of the species, establishing and defending territories in which they build their nests. Although most male-male encounters consist solely of the resident lunging at an intruder, if this fails to drive off the intruder, the resident may bite. Females choose to mate with males that have large territories and well-constructed nests. What would you expect to happen as nest sites become scarcer? A) Females will begin to choose mates that have no territories. B) The incidence of biting and other aggressive behaviors will increase. C) Nest construction will deteriorate. D) Males will make their territories even larger. E) The color of the males will fade. Answer: B SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 115) Viceroy butterflies, which are nontoxic, have color patterns that closely mimic those of monarch butterflies, which are toxic. When monarchs are common and viceroys are scarce in the same environment, viceroys are protected because birds cannot distinguish them from monarchs. If monarchs become scarce and viceroys much more common, what do you predict will happen? Answer: Viceroys will be eaten more frequently because few birds have had recent bad experiences with monarchs.

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 116) Martha McClintock found that the menstrual cycles of female college roommates became synchronous after 6 months of living together. She also found that armpit odors from one group of women affected the menstrual cycles of other women who sniffed the odors. These findings might indicate that A) menstrual cycles are not influenced by nerve impulses. B) something in the water in the dorm influences the women's cycles. C) women have conscious control over their menstrual cycles. D) eating the same foods causes menstrual cycles to become synchronous. E) pheromones are involved in menstrualsynchrony. Answer: E

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) The study of how organisms interact with one another and with their nonliving environment is A) anatomy. B) genetics. C) morphology. D) ecology. E) ecosystems. Answer: D 2) In a deciduous oak forest in the northeastern United States, one example of a nonliving component of the ecosystem is A) sunlight that filters through thecanopy. B) nematodes in the soil that feed on plant roots. C) the smaller plants living under the oak trees. D) nematodes in the soil that feed on dead organic matter. E) animals such as deer that migrate through the forest but do not eat in the forest. Answer: A 3) Floods and fires are examples of A) demographic factors B) logistic growth factors C) environmental resistance D) density-dependent factors E) biotic factors

, which can dramatically and unpredictably reduce populations.

Answer: C 4) A complex, interrelated network of organisms and the surrounding nonliving environment in a defined area is a(n) A) community. B) biosphere. C) population. D) ecosystem. E) biome. Answer: D 5) A population grows exponentially when A) the death rate equals the birth rate and immigration is equal to emigration. B) the birth rate exceeds the death rate and immigration exceeds emigration. C) the carrying capacity is exceeded. D) the birth rate and the death rate are equal. E) emigration exceeds immigration and the birth rate equals the death rate. Answer: B 6) The different species within an ecosystem that interact in various ways make up a(n) A) community. B) aggregation. C) ecotone. D) trophic level. E) population. Answer: A

7) All members of a species that reside within an ecosystem make up a(n) A) ecotone. B) community. C) population. D) trophic level. E) aggregation. Answer: C 8) Based on the data in the table, this population has a Time (years) 1998 2000 2002 2004 2006

growth pattern.

Number of Organisms 10 15 20 40 80

A) replacement-level fertility B) S-curve C) scramble competition D) J-curve E) boom-and-bust Answer: D 9) Environmental resistance may limit the size of populations by A) increasing both birth and deathrates. B) decreasing death rates and/or increasing birth rates. C) decreasing both birth and deathrates. D) changing the biotic potential. E) increasing death rates and/or decreasing birth rates. Answer: E 10) To determine the number of individuals added to a population during a given time, multiply the growth rate (r) by the A) environmental resistance. B) biotic potential. C) original population size. D) final population size. E) number of immigrants. Answer: C 11) If a population of 100 birds increases to 120 birds in a year, what is the value of r? A) 2 B) 0.16 C) 0.20 D) 1.2 E) 20 Answer: C

12) Which factor does NOT influence the size a population reaches through natural increase? A) Number of births B) Distance traveled by migrants C) Number of deaths D) Age of females at reproduction E) Frequency of reproduction Answer: B 13) Environmental resistance is A) limits imposed on population growth by both the living and nonliving environments. B) a factor that increases both death rates and birth rates. C) a factor that decreases both death rates and birth rates. D) limits imposed on population growth by only the living environment (e.g., predators or competitors). E) limits imposed on population growth by only the nonliving environment. Answer: A 14) Exponential growth occurs when A) the biotic potential decreases eachyear. B) the population grows by a fixed percentage of its size each year. C) environmental resistance declines each year. D) the rate of emigration is higher than the rate of immigration. E) the number of births each year is constant and the birth rate is higher than the death rate. Answer: B 15) A population size will remain stable if A) the number of births each year is constant and the birth rate is higher than the death rate. B) environmental resistance declines each year. C) the rate of emigration is higher than the rate of immigration. D) the birth and death rates are equal, as are the rates of emigration and immigration. E) the population grows by a fixed percentage of its size each year. Answer: D 16) Which species has the highest biotic potential? A) A rat that produces a litter of six pups every 3 months B) A bacteria that divides only once every 3 weeks C) A fungus that produces thousands of reproductive spores every day D) An elephant that produces a single calf every 3 years E) A lioness that produces three cubs once a year Answer: C 17) When a population has inhabited an area for a long time and the population size has stabilized, then A) density-independent factors are involved. B) predation decreases. C) the carrying capacity of the area has been reached. D) density dependence is clearly not involved in the population growth. E) the environmental resistance declines. Answer: C

18) An insect population grows exponentially until an early winter freeze kills almost all of the insects. The next spring, the population grows exponentially again. This type of population growth is called A) S-curve growth. B) sustained cycling. C) density-independent growth. D) boom-and-bust cycles. E) density-dependent growth. Answer: D 19) Based on the data in the table, this population has a(n) Time (years) 1998 2000 2002 2004 2006

growth pattern.

Number of organisms 200 15 175 30 215

A) J-curve B) S-curve C) exponential D) scramble competition E) boom-and-bust Answer: E 20) Which of the following is an important density-independent factor limiting population size? A) Weather B) Competition C) Environmental resistance D) Predation E) Quantity of food Answer: A 21) If a caterpillar eats all of the seedlings in your garden, killing all of them, the caterpillar is acting as a A) saprophyte. B) parasite. C) predator. D) competitor. E) density-independent factor. Answer: C 22) Some predators feed primarily on the most abundant prey. This is an example of A) exponential B) cyclical C) competitive D) density-independent E) density-dependent Answer: E

predation.

23) Why do many non-native species, such as a prickly pear cactus brought to Australia from South America, rapidly become abundant when first introduced? A) Non-native species increase their reproductive rate when introduced. B) There are fewer predators and parasites capable of attacking the non-native species in the new site. C) The carrying capacity at the new site is higher than that at the native site. D) Growth changes from an S-curve to a J-curve at the new site. E) The climate in the new site is more favorable than in its native site. Answer: B 24) Which of the following correctly describes the effect parasites have on their host's population size and on the host itself? A) Parasites have a density-dependent effect, and they usually kill their hosts. B) Parasites have a density-dependent effect, but they do not affect host death rates. C) Parasites have a density-independent effect, and they usually kill their hosts. D) Parasites have a density-dependent effect, but they do not usually kill their hosts. E) Parasites have a density-independent effect, but they do not usually kill their hosts. Answer: D 25) When mosquitoes are abundant, purple martins flock to the area and feed exclusively on them. When mosquito populations are not large, purple martins are similarly scarce and feed on other insects. This is an example of A) exotic regulation. B) density-dependent regulation. C) community carrying capacity. D) density-independent regulation. E) ecosystem carrying capacity. Answer: B 26) Purple loosestrife, a European plant, was introduced into the American Great Lakes region where it has no natural predators. Each plant produces thousands of seeds annually, and it now clogs acres of wetlands, crowding out native plants. Purple loosestrife is considered a(n) A) invasive species. B) density-dependent species. C) replacement-level fertility species. D) density-independent species. E) predator. Answer: A 27) A population of birds migrating to winter nesting grounds is blown off course by a late-season hurricane and ends up on an island that is uninhabited by any animal species. Which of the following represents a density-independent factor that will limit the population size? A) Nightly temperature dropping below freezing B) Abundant berry bushes C) Heavily wooded D) Freshwater spring E) Abundant fruit trees Answer: A

28) A population of rabbits introduced into an island grew rapidly for a few years and then the growth slowed down and stabilized. Why did the population become stable? A) A bust cycle was about to begin. B) Environmental resistance declined. C) The value of r decreased. D) The rate of immigration declined. E) The carrying capacity was reached. Answer: E 29) In a population of lemmings, a sudden freeze that caused many of the lemmings to die is an example of a A) living and density-dependent factor. B) nonliving and density-dependent factor. C) normal boom-and-bust cycle. D) nonliving and density-independent factor. E) living and density-independent factor. Answer: D 30) Exponential growth occurs A) only in laboratory populations. B) frequently in natural populations. C) only for a limited time in natural populations. D) at regular intervals in natural populations. E) only in theory, never in actual populations. Answer: C 31) Schools of fish typically exhibit a A) uniform B) random C) J-curve D) scrambled E) clumped

distribution pattern.

Answer: E 32) If most of the individuals of a species die when they are young, that species exhibits a(n) curve. A) constant-loss B) late-loss C) S-shaped D) early-loss E) declining

survivorship

Answer: D 33) If the individuals of a species are likely to live until old age, that species exhibits a(n) curve. A) constant-loss B) S-shaped C) late-loss D) declining E) early-loss Answer: C

survivorship

34) What might cause a uniform population distribution? A) The need to hunt in a group B) The need for a group to care for its offspring C) Scarce resources D) The need to finda mate E) Competition for resources Answer: E 35) A random population distribution A) is an advantage in avoiding predators. B) is found only in plants. C) allows predators to huntmore effectively. D) is rare. E) occurs when resources are evenly spaced. Answer: D 36) In the eighteenth and nineteenth centuries, people increased Earth's capacity to support more humans through advances. A) cultural B) industrial-agricultural C) psychological D) demographic E) social-medical Answer: B 37) In areas that have a stable population, the number of children born in a period of time is A) decreasing. B) higher than the number ofadults. C) increasing. D) lower than the number ofadults. E) approximately equal to the number of adults. Answer: E 38) In countries that have large numbers of children under age 15, the population is A) able to expand its carrying capacity. B) staying the same. C) becoming larger. D) hard to predict. E) becoming smaller. Answer: C 39) In countries where the number of children younger than 15 is approximately equal to the number between ages 15 and 45, the populationis A) expanding slowly. B) stable. C) growing exponentially. D) declining drastically. E) shrinking slightly. Answer: B

40) Developing countries tend to have a(n) A) triangular-shaped B) square C) inverted-triangle-shaped D) round E) rectangular

age structure diagram.

Answer: A 41) To support the world population at the same standard of living as we have in the United States would require times the resources that are available on Earth today. A) 10 B) 2 C) 1.5 D) 5 E) 20 Answer: D 42) The United Nations estimates that by 2050, the world's population may reach over growing. A) 20 B) 9 C) 7 D) 15 E) 12

billion and still be

Answer: B 43) If all the people in the world were to live at the American level in terms of technology, wealth, education, and other factors, the population of the world would have to to support them. A) reduce to a fifth of the current level B) reduce to less than a tenth of the current level C) double D) decrease by 90% E) reduce by half Answer: A 44) At present, Earth's human populationis A) declining. B) increasing at a constant rate. C) stable. D) increasing by about 10% per year. E) increasing exponentially. Answer: E 45) As a developing country passes through the demographic transition, which of the following will occur? A) Its growth rate will first fall, but later recover. B) Its age structure will change, but its growth rate will remain unchanged. C) Its birth and death rates will decrease simultaneously. D) First, its death rate will decrease, followed by its birth rate. E) First, its birth rate will decrease, followed by its death rate. Answer: D

46) The prediction, during the early 1800s, that our human population would eventually reach a point where we cannot sustain ourselves has not occurred. Why? A) Dramatic reductions in fertility rates ended population growth before the crisis point was reached. B) Humans continue to find ways to enhance environmental quality, thus enabling more people to be supported. C) Technological advances unforeseen at that time increased the carrying capacity to a greater extent and faster than predicted. D) The two world wars and the AIDS crisis caused such massive mortality that the human population has stabilized. E) The prediction was wrong; human populations can grow indefinitely. Answer: C 47) What percentage of Earth's productive land is currently used by the human population for crops and livestock? A) 20% B) 90% C) 40% D) 75% E) 55% Answer: C 48) The growth rate of a population is the difference between the population size and the death rate. A) True B) False Answer: B 49) According to the equation for population growth rate, if two populations have the same death rates, then the population with r = 2 will increase more rapidly than a population with r = 4. A) True B) False Answer: B 50) A J-curve is typical of a stable population. A) True B) False Answer: B 51) A forest fire is a density-independent population control factor. A) True B) False Answer: A 52) Parasitism is a density-dependent populationcontrol. A) True B) False Answer: A 53) Interspecific competition is a density-independentfactor. A) True B) False Answer: B

54) An effective parasite is one that kills its host quickly. A) True B) False Answer: B 55) Invasive species can rapidly disrupt an ecosystem because they have a high biotic potential and face little environmental resistance. A) True B) False Answer: A 56) Logistic population growth is characteristic of a population that moves into a new habitat, experiences a rapid increase in number, and thenstabilizes. A) True B) False Answer: A 57) Populations that have been relatively undisturbed by humans normally grow, with no limits set by their environments. A) True B) False Answer: B 58) Prey, such as lemmings, may have a density-dependent effect on predator populations, such as those of the snowy owl, by enabling the predator to increase the number of its offspring at high prey densities. A) True B) False Answer: A 59) Natural populations cannot exceed their carrying capacities. A) True B) False Answer: B 60) Density-dependent factors become less effective as the population size increases. A) True B) False Answer: B 61) Increased population densities and increased competition lead to increased emigration. A) True B) False Answer: A 62) In a constant-loss population, an organism has an equal risk of dying at any time during its life span. A) True B) False Answer: A

63) Within their territory, pack animals such as wolves exhibit a uniform distribution. A) True B) False Answer: B 64) When resources are limited but spread evenly throughout a region, plants are likely to form a uniform distribution pattern. A) True B) False Answer: A 65) Humans are classified as a late-loss population. A) True B) False Answer: A 66) The human population currently shows a J-curve growth pattern. A) True B) False Answer: A 67) The collective human ecological footprint is now much larger than Earth's sustainable resource base. A) True B) False Answer: A 68) Deforestation increases the productivity of land. A) True B) False Answer: B 69) When parents, on average, have just the number of children required to replace themselves, the natural increase of their population is at replacement level fertility (RLF). A) True B) False Answer: A 70) In a stable population with neither immigration nor emigration, the RLF is 1.0 (one child per woman). A) True B) False Answer: B 71) Although social changes and increased access to contraceptives have caused a decrease in fertility rates in some less-developed countries, their rates are still above RLF. A) True B) False Answer: A

SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 72) All the members of a species that live within an ecosystem form a(n)

Answer: population 73) The

is made up of the entire Earth and all of the living organisms that inhabit it.

Answer: biosphere 74) The maximum rate at which a population could increase is known as its

Answer: bioticpotential 75) A measure of the ability of a population to grow under ideal circumstances (maximum birth rate and minimum death rate) is its . Answer: biotic potential 76) The sum of all factors (living and nonliving) that limit the ability of a population to grow is known as Answer: environmentalresistance 77) In the equation, population growth = r × N, the letter r stands for

Answer: growthrate 78) In a maple forest in the spring, the ground is often covered with young maple seedlings, which compete for light and nutrients. By fall, most of the seedlings have died, leaving only a few survivors. This is an example of life history pattern. Answer: early-loss 79) A population that initially grows rapidly, then slows, and eventually stabilizes close to the carrying capacity of the environment exhibits population growth. Answer: logistic (or S-shaped) 80) When predators and prey both have population cycles, the predator cycle tends to cycle.

that of the prey

Answer: lag behind 81) Predation is considered to be a density-

factor that controls the size of the prey population.

Answer: dependent 82) Competition among individual members of the same species is referred to as

competition.

Answer: intraspecific 83) Density-dependent factors become more effective at limiting population growth as the size of the population . Answer: increases 84) A species that is transferred to a new environment where it has little environmental resistance and experiences an explosive population growth is called a(n) species. Answer: invasive

85) Human populations have continued to grow because humans have increased Earth's agriculture, medicine, and technology.

through

Answer: carrying capacity 86) If adults of reproductive age are having just enough children to replace themselves, then the population is said to have fertility. Answer: replacement level 87) How does environmental resistance affect a population? Answer: Environmental resistance limits population growth or may even reduce the size of the population. 88) Write an equation that describes a situation in which a population remains stable. Answer: Birth + immigration = death + emigration, or r = (birth rate + immigration rate) - (death rate + emigration rate ) = 0. 89) How does the environment limit population growth? Answer: Competition, predation, limits on nutrients and space, disease, and weather are all factors in environmental resistance, which limits the growth of populations. 90) Explain what happens in exponential population growth. Answer: The population grows by a fixed percentage of its size during each time period, so that the actual number of individuals added to the population grows at an ever-increasing rate. 91) In the United States today, there is a trend toward women having their first child in their late 30s or early 40s. In contrast, a few decades ago, most women started having children in their early 20s. What effect would you expect this change to have on population growth in the United States? Would it have any effect if the number of children per woman remains the same? Explain. Answer: Population growth would be expected to slow even if the number of offspring per woman remains the same because the effective generation time has increased. The growth curve would be extended over a slightly longer time scale. 92) What factors determine the natural increase of a population? Answer: The growth rate is based on the birth rate minus the death rate. 93) Why does a bacteria population have a higher biotic potential than a population of humans? Answer: A bacteria population can increase more rapidly than a human population because each bacteria cell can reproduce every 20 minutes, whereas humans reproduce less often and begin reproducing at an older age. 94) How do interspecific and intraspecific competition differ? Answer: Interspecific competition occurs between members of different species, whereas intraspecific competition occurs between members of the same species. 95) What term describes the maximum population size that the environment can support indefinitely? Answer: carryingcapacity 96) What is thetermforregularpopulationcyclesofrapidgrowthfollowedbymassivedie-off? Answer: boom-and-bust cycles

97) Predation is considered a density-dependent factor that controls the population size of prey species. Give two examples of predators acting in density-dependent ways in response to fluctuations in the size of prey populations. Answer: Predators may adjust the number of prey that they eat in response to the abundance of their prey. They might switch to alternative food sources when prey are scarce or feed exclusively on the prey that is abundant. In addition, predators may regulate the number of offspring they produce in response to the abundance of their prey. 98) Parasites often kill their hosts, although they do not directly benefit from their hosts' death. Yet many ecologists believe that parasites may have beneficial effects on their host populations. Why? Answer: Parasites tend to destroy weaker and less fit hosts, leaving the stronger or better-adapted hosts to reproduce and pass genes on to the next generation. Thus, the host population is regulated, but very fit individuals are not eliminated. 99) Which tends to be more intense: intraspecific or interspecific competition? Why? Answer: Intraspecific competition tends to be more intense because individuals of the same species all need similar resources. 100) Why has it been so hard to come up with an accurate measure of Earth's carrying capacity for humans? Answer: Humans have the ability to increase their own carrying capacity through technological revolutions in agriculture, industry, and medicine. 101) What factors determine Earth's carrying capacity for humans? Answer: Human carrying capacity is determined by the amount of water, light, nutrients, and space available to sustain the maximum human population size indefinitely.

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

102) According to the graph, how long does it take the population of deer that is experiencing moderate growth (r = 0.2) to reach 3,000 deer? A) 35 years B) 20 years C) 15 years D) All three populations grow at the same rate. E) None of the three populations grows to 3,000. Answer: A 103) Which population represented on the graph has the highest biotic potential? A) The population represented by the middle curve has the highest biotic potential. B) The population represented by the curve on the left has the highest biotic potential. C) The population represented by the curve on the right has the highest biotic potential. D) All three populations have the same biotic potential. Answer: D

104) The population shown in the graph is demonstrating

A) exponential growth. B) logistic population growth. C) an S-curve growth pattern. D) clumped distribution. E) a typical boom-and-bust pattern. Answer: E 105) The population shown in the pyramid is

A) showing continuous exponential growth. B) decreasing. C) stable, or slowly growing. D) going through a boom-and-bustcycle. E) expanding. Answer: C

106) Based on its population pyramid, this population

A) is in a boom-and-bustcycle. B) is showing negative growth. C) is remaining the same. D) has reached its carrying capacity. E) is expanding, or rapidly growing. Answer: E 107) At the start of a study, 200 spotted owls lived in an old-growth forest patch in western Oregon. During the next year, a biologist tracking the birds observed that 25 new birds hatched and 5 died. What was the growth rate (r) for this year? A) 25 B) 0.1 C) 200 D) 20 E) 5 Answer: B 108) An ecologist is studying the painted turtle population in a small pond. At the beginning of the year, there are 100 individuals. Over the course of a year, 40 turtles are born and 60 die. There is no migration. What is the birth rate per year for this population? A) 40 B) 20 C) 0.6 D) 60 E) 0.4 Answer: E

109) An ecologist is studying the painted turtle population in a small pond. At the beginning of the year, there are 100 individuals. Over the course of a year, 40 turtles are born and 60 die. There is no migration. What is the growth rate (r) of the painted turtle population? A) -0.4 B) 0.2 C) 0.4 D) 0.6 E) -0.2 Answer: E 110) Many species of field mice are able to reproduce several times a year and produce litters with multiple offspring. However, an ecologist noted that the population size of mice, as measured in a California grassland, did not change from year to year. The factors that keep natural populations from increasing are collectively called A) nonliving factors. B) biotic potential. C) exponential growth. D) scramble competition. E) environmental resistance. Answer: E 111) During the winter of 1999, minimum temperatures did not get much below freezing in an Oregon pond, and the following summer, large mosquito populations were observed. In the winter of 2000, frost came early and most ponds were frozen for 3 months. The following summer, very small mosquito populations were observed. This is an example of A) exotic regulation. B) density-dependent regulation. C) density-independent regulation. D) community carrying capacity. E) ecosystem carrying capacity. Answer: C 112) A laboratory experiment followed the growth of a flour beetle (Tribolium sp.) population over time. At first, the population increased dramatically, but later the growth slowed and the population size leveled off. Although food (the wheat flour in which they live) was still abundant, the flour beetles resorted to eating their own eggs when population densities got high. What can we conclude about cannibalism in this species? A) It has no effect on the growth of the population, as food scarcity is clearly the limiting factor. B) We cannot reach any conclusions based on the information provided. C) It is a density-independent means of population control. D) It is clearly maladaptive, as populations always do best when their densities increase as much as possible. E) It is a density-dependent means of populationcontrol. Answer: E

113) Zebra mussels were introduced into Lake St. Clair around 1988. The table lists the population densities (in grams dry weight per square meter of lake bottom) of native unionid mussels and exotic zebra mussels in the lake before and after this introduction. Both groups feed by filtering small particles from the water. Based on the information given, which of the following best describes the likely relationship between zebra mussels and unionids? Year 1986 1990 1992 1994

Unionids 4.5 3.7 1.3 0.1

Zebra mussels 0.0 4.6 3.4 3.2

A) Unionids exert a density-dependent control on zebra musselpopulations. B) Zebra mussels exert a density-dependent control on unionid populations. C) Zebra mussels and unionids have no effect on each other. D) Zebra mussels exert a density-independent control on unionid populations. E) Unionidsexertadensity-independentcontrolonzebramusselpopulations. Answer: B 114) A small country begins to experience stable economic prosperity after centuries of extreme poverty. The government uses the taxes generated for educating all members of the population and creating a comprehensive health care system for all of its citizens. A social security system is established to support elderly members of the population. What demographic changes would you expect to see? A) Earlier childbearing and many more children per woman, with a decrease in the number of elderly people B) No changes in thepopulation C) Large numbers of elderly people and no children D) A decrease in the number of deaths and an increase in the number of births and delayed childbearing E) Reproductive rates far below replacement-level fertility Answer: D

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) In the process called , interactions between species can limit population size, but can also influence the physical characteristics and behaviors of the interacting populations. A) succession B) mutualism C) symbiosis D) coevolution E) camouflage Answer: D 2) The biologist who studies interactions at the community level investigates interactions among A) organisms of more than onespecies. B) organisms of one species. C) social animals (such as honeybees). D) ecosystems. E) animals of one species. Answer: A 3) Over the course of their evolutionary histories, the timing of flowering, the spacing of plants, and the nectar rewards of flowering plants have influenced the foraging behavior of bees, which in turn has influenced the morphology of flowers. This process is an example of A) niche partitioning. B) adaptive radiation. C) competitive exclusion. D) coevolution. E) convergent evolution. Answer: D 4) Predation is similar to harming the other. A) coevolution B) mutualism C) symbiosis D) parasitism E) competition

in that both types of relationship benefit one of the interacting species while

Answer: D 5) In

, the interaction between two species harms both of them. A) symbiosis B) mutualism C) competition D) coevolution E) parasitism

Answer: C

6) The process by which two interacting species act as agents of natural selection on one another is called A) mutualism. B) parasitism. C) symbiosis. D) mimicry. E) coevolution Answer: E 7) An ecological niche A) cannot be shared by two species. B) is a constantly changing place. C) depends on the weather. D) is formed by the physical environment only. E) is the same thing as a habitat. Answer: A 8) Competition between the members of two species is A) least intense between similar species and is referred to as interspecific. B) very common and is referred to as intraspecific. C) always very intense and is referred to as intraspecific. D) most intense when the species are most similar and is referred to as interspecific. E) unusual and is referred to as interspecific. Answer: D 9) Two species that have a high degree of niche overlap will A) split into two separate species. B) compete intensely. C) be in a predator-prey relationship. D) coexist peacefully. E) interbreed. Answer: B 10) If similar species each occupy a smaller niche when they live together than they would if they lived alone, they are said to be A) partitioning their resources. B) involved in succession. C) coevolving. D) involved in intraspecific competition. E) increasing niche overlap. Answer: A 11) The concept that two species cannot occupy the same ecological niche at the same time is called A) the competitive exclusion principle. B) succession. C) coevolution. D) predation. E) mutualism. Answer: A

12) Ornithologists visiting an island find two species of birds that appear nearly identical except for bill size. Which of the following is the most likely explanation for their discovery? A) Coevolution of the two species has resulted in resource partitioning between the species. B) Mutations have resulted in an inferior species with defective bills. C) They are not separate species. D) The birds need camouflage for protection from predators. E) There is natural random variability. Answer: A 13) Earthworms live in many grass and forest ecosystems, and they aerate the soil as they burrow. They also may mix soil layers as they ingest organic matter and travel between layers. These traits, taken collectively, make up the of the earthworm. A) resource partition profile B) ecosystem profile C) niche D) physical home E) community profile Answer: C 14) Two species of buttercup are found in the same field in South Dakota, but they emerge at different times: One species emerges and flowers in early spring, and the other species does not emerge until late summer, after the first species has set seed. This is an example of A) resource partitioning. B) niche realignment. C) niche fragmentation. D) intraspecific competition. E) habitat fragmentation. Answer: A 15) Over the past century, sagebrush has dramatically expanded its range over the Colorado plateau's grasslands. This development has been attributed to the overgrazing of the area's grasses by cattle and sheep. This example indicates that A) the relationship between sagebrush and grasses is mutualistic. B) sagebrush is the dominant competitor over grasses. C) sagebrush could not exist anywhere in the absence of cattle and sheep. D) the range of sagebrush is normally limited by competition with grasses. E) grazing has no effect on the distribution of plants. Answer: D 16) Two families of feral cats move into the same barn. One family preys on the mice; the other preys on the pigeons. This behavior is an example of A) resource partitioning. B) mutualism. C) ecosystem profile. D) interspecific competition. E) parasitism. Answer: A

17) If an insect eats the lettuce seedlings in your yard, it is acting most like a(n) A) mutualist. B) omnivore. C) herbivore. D) host. E) carnivore. Answer: C 18) If you find a brightly colored insect resting on a dead leaf, the insect is likely to A) be camouflaged. B) be prey forbirds. C) have aggressive mimicry. D) have startle coloration. E) be poisonous ordistasteful. Answer: E 19) An effective, bright, and very distinct color pattern that a prey species can display suddenly to scare a predator is called A) modeling. B) mimicry. C) camouflage. D) aggressive mimicry. E) startle coloration. Answer: E 20) A species that is a mimic will most likely A) resemble its surroundings. B) use bright colors to warn that it is harmful. C) produce chemicals that deter predators. D) have a behavior similar to that of a more toxic species. E) produce "smoke screens." Answer: D 21) A species of caterpillar develops toxic spikes that deter the birds that prey on it. Over time, the genetics of the bird population shifts so that an allele for a digestive enzyme that neutralizes the toxin becomes more common. This is an exampleof A) mimicry. B) an invasive species. C) mutualism. D) parasitism. E) coevolution. Answer: E 22) A predator might use A) warning coloration B) startle coloration C) camouflage D) symbiosis E) coevolution

to enable it to catch its prey.

Answer: C

23) Which behavioral response to the threat of predation is most likely to be selected for in a species that uses camouflage for protection from predators? A) Motionless behavior B) A quick escape response C) Cooperative behavior D) Behavior that mimics the behavior of the predator E) Sudden display to startle the predator Answer: A 24) Trees often produce secondary chemicals to deter herbivores from feeding on their leaves; in turn, many herbivores have developed ways of avoiding or detoxifying these chemicals. This is an example of A) parasite predation. B) predatory avoidance. C) competitive exclusion. D) parasitic evolution. E) coevolution. Answer: E 25) Harmless king snakes mimic the color patterns of venomous coral snakes, which serve as models. If avoidance were based solely on prior predator experience with the model, what do you predict would happen in areas where coral snakes were neverpresent? A) Predators would avoid king snakes. B) Predators would initially avoid king snakes but soon learn to attack and eat them. C) Predators would attack and eat king snakes. D) No predictions can be made based on the information given. E) Predators would initially attack and eat king snakes but soon learn to avoid them. Answer: C 26) In the Australian outback, emus (a relative of the ostrich) feeding in the open brush lands have coloration similar to the surrounding bushes. This is an example of A) mimicry. B) warning coloration. C) interspecies competition. D) coevolution. E) camouflage. Answer: E 27) Fleas on a dog are an example of A) predators. B) parasites. C) hosts. D) mutualists. E) prey. Answer: B

28) Insects that feed on plants without completely consuming them may be classified as A) predators. B) parasites. C) hosts. D) mutualists. E) prey. Answer: B 29) Mosquitoes are A) predators. B) parasites. C) hosts. D) mutualists. E) prey. Answer: B 30) In the rain forests of Panama, scientists found a colony of tree-dwelling black ants where some individuals had red abdomens. When examined, the scientists determined that the ants with red abdomens were infected with roundworm eggs. Birds would prey on these ants, mistaking their red bellies for berries. In the interactions among the tree-dwelling black ants, the roundworms, and the birds, the ants are the for the roundworms. A) predators B) parasites C) hosts D) mutualists E) prey Answer: C 31) In the rain forests of Panama, scientists found a colony of tree-dwelling black ants where some individuals had red abdomens. When examined, the scientists determined that the ants with red abdomens were infected with roundworm eggs. Birds would prey on these ants, mistaking their red bellies for berries. In the interactions among the tree-dwelling black ants, the roundworms, and the birds, the roundworms are the A) predators. B) parasites. C) hosts. D) mutualists. E) prey. Answer: B 32) Humans contract bacterial infections such as tuberculosis or syphilis. What is this ecological relationship called? A) Mutualism B) Resource partitioning C) Predation D) Parasitism E) Competition Answer: D

33) Fleas feed on the blood of dogs, cats, and people. What is this ecological relationship called? A) Competition B) Resource partitioning C) Parasitism D) Predation E) Mutualism Answer: C 34) Many plants are mycorrhizal: Their roots are infected with a specialized fungus. The plant supplies carbon to the fungus, and the fungus supplies nutrients to the plant. The relationship between these plants and the mycorrhizal fungi is an example of a association. A) parasitic B) competitive C) mutualistic D) predator-prey E) successional Answer: C 35) Clownfish live within the tentacles of sea anemones. The anemone protects the fish from predators, and the clownfish cleans the anemone. This relationship is an example of A) succession. B) predation. C) competition. D) parasitism. E) mutualism. Answer: E 36) The Masai people of Kenya, in east Africa, regularly consume the blood and milk of their cattle. Based on this information alone, we might classify the relationship between the Masai and cattle as A) coevolution. B) parasitism. C) mutualism. D) predation. E) competition. Answer: B 37) The Masai people of Kenya, in east Africa, regularly consume the blood and milk of their cattle. The cattle derive a net benefit because the Masai also protect them from predators and help them find water and food. Based on this information, the relationship between the Masai and cattle is best classified as A) parasitism. B) competition. C) predation. D) coevolution. E) mutualism. Answer: E

38) Plants called legumes have chambers in their roots that house nitrogen-fixing bacteria. Nitrogen-fixing bacteria get both a place to live and energy while supplying nitrogen to a plant. What is this ecological relationship called? A) Parasitism B) Mutualism C) Predation D) Succession E) Competition Answer: B 39) An example of is when birds feed on parasitic insects that they pick off the skin of large animals such as elephants or bison. A) competition B) mutualism C) predation D) resource partitioning E) parasitism Answer: B 40) Birds follow a herd of water buffalo to catch insects that are disturbed as the large herbivores walk through the grass. When large predators are near, the birds fly into the air and make warning calls. What is the ecological relationship between the birds and the herbivores called? A) Resource partitioning B) Predation C) Competition D) Parasitism E) Mutualism Answer: E 41) Birds follow a herd of water buffalo to catch insects that are disturbed as the large herbivores walk through the grass. When large predators are near, the birds fly into the air and make warning calls. Who are the birds warning? A) The water buffalo's prey, because they need to escape B) The predators, so they know their prey, the water buffalo, is near C) Other birds, who also catch insects stirred up by the water buffalo D) The water buffalo, so they can avoid attack E) Their competitors Answer: D 42) A species that plays a major role in determining the structure of its ecological community is A) a keystone species. B) a predator. C) the species with thelargest size. D) a dominator species. E) the most abundant species in the community. Answer: A

43) Why is the African elephant considered a keystone species? A) It is the largest organism in its community. B) The removal of elephants from their community would result in drastic changes in the ecological structure of the community. C) Elephant populations are larger than the populations of any other organisms in their community. D) Elephants live in large cooperative herds that dominate other smaller groups within the community. E) Elephants eat more food than any other species in their community. Answer: B 44) A certain species of animal represents just 3% of the biomass in its ecosystem. We might classify this as a keystone species if its removal A) caused 2% of the other species in the community to disappear. B) caused plant biomass to increase by 5%. C) allowed an even rarer species to increase in number and take its place. D) caused the diversity of the plant community to decline by 40%. E) had no effect on the community. Answer: D 45) Succession that begins on bare rock after glaciers have passed, or on newly formed volcanic islands, is A) secondary. B) pioneer. C) allogenic. D) primary. E) autogenic. Answer: D 46) The first community that forms on bare rock often has organisms such as A) lichens and mosses. B) woody shrubs and conifers. C) herbs andconifers. D) grasses and weeds. E) broad-leaf trees and conifers. Answer: A 47) After a forested area such as a national forest is clear-cut, what type of succession occurs? A) Primary B) Climax C) Subclimax D) Biome E) Secondary Answer: E 48) A storm strips an island in Lake Superior down to bare rock. The first organisms to recolonize the island are most likely A) yarrow. B) junipers. C) blueberries. D) balsam firs. E) lichens. Answer: E

49) The next time you need to mow the grass, you can excuse yourself, saying that by mowing you are helping to maintain a man-made A) ecosystem. B) population. C) subclimax community. D) biome. E) climax community. Answer: C 50) When a community like the tallgrass prairie is maintained by recurring disturbances such as periodic fires set by Native Americans or by lightning, a community exists. A) pioneer B) climax C) deciduous D) pine forest E) subclimax Answer: E 51) What ecological process causes a lake to change into a marsh over a long period of time? A) Extinction B) Competitive exclusion C) Eutrophication D) Succession E) Coevolution Answer: D 52) The biotic portion of an ecosystem includes the plants, animals, and water. A) True B) False Answer: B 53) In a process called coevolution, two species exert natural selection pressures on each other. A) True B) False Answer: A 54) In mutualistic interactions, one species is harmed and one benefits. A) True B) False Answer: B 55) In most environments, two or more organisms occupy identical niches. A) True B) False Answer: B 56) Woodpeckers and squirrels both nest in tree cavities. This is an example of interspecific competition. A) True B) False Answer: A

57) Intraspecific competition limits population size. A) True B) False Answer: A 58) In a stable ecosystem, the number of predators is greater than the number of prey. A) True B) False Answer: B 59) Some toxic animals are brightly colored, as a means of warning others of their danger. A) True B) False Answer: A 60) Invasive species outcompete native species because they lack predators and have high reproductive rates. A) True B) False Answer: A 61) Organisms introduced as biocontrols for an invasive species can harm native species. A) True B) False Answer: A 62) Startle coloration is used to attract mates. A) True B) False Answer: B 63) Hawks that eat field mice are practicing mutualism. A) True B) False Answer: B 64) Parasites kill their hosts, but predators do not kill their prey. A) True B) False Answer: B 65) Parasitism is a relationship in which one species benefits and the other does not benefit. A) True B) False Answer: A 66) Parasites are generally smaller than their host. A) True B) False Answer: A

67) In all symbiotic relationships, both species involved benefit from the association. A) True B) False Answer: B 68) In a mutualistic relationship, one species benefits and the other is harmed. A) True B) False Answer: B 69) A lichen is a mutualistic relationship between a fungus and an alga. A) True B) False Answer: A 70) Lichens represent a symbiotic association between a fungus and a plant. A) True B) False Answer: B 71) A keystone species is the most numerous species in an ecosystem. A) True B) False Answer: B 72) The keystone species in the African savanna is the elephant. A) True B) False Answer: A 73) Shade-tolerant plant species are generally found early in succession and are replaced by hardier, shade-intolerant species. A) True B) False Answer: B 74) The first organisms to colonize a disturbed ecosystem are the climax species. A) True B) False Answer: B 75) The most common pioneer species are mosses and lichens. A) True B) False Answer: A SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 76) The physical home of a species is its

Answer: habitat

77) Every species occupies a unique ecological

that encompasses all aspects of its way of life.

Answer: niche 78) The time.

principle states that two species cannot occupy the same niche in the same habitat at the same

Answer: competitive exclusion 79) Two weed species live in the same patch of ground. One has deep roots to tap into ground water. The other has broad, shallow roots to take advantage of the frequent light rains that do not penetrate very deeply into the soil. This is anexample of . Answer: resource partitioning 80) An animal that only eats plants is a(n)

Answer: herbivore 81) The bright coloration of toxic tree frogs is an example of

Answer: warningcoloration 82) The spotted brown and black coats of mountain lion cubs make it difficult for predators to find them. This is known as . Answer: camouflage 83) A predator lures its prey nearby by looking like the prey's favorite food. This is referred to as

Answer: aggressivemimicry 84) A

feeds on its host organism, but does not kill it immediately.

Answer: parasite 85) Parasites act asagents of parasite.

, leading to changes in the host population that make it more resistant to the

Answer: natural selection 86) A bat pollinates a plant while obtaining nectar from it. This behavior is an example of

Answer: mutualism 87) A protist lives in the gut of a termite, breaking down the cellulose that the termite ingests and providing glucose to benefit both of them. This kind of relationship is called . Answer: mutualism 88) Bison are a species in the prairie, helping to maintain the grasses, opening water holes and wallows, and creating the ecological framework for the prairie ecosystem. Answer: keystone 89) When all vegetation is removed from a site by human activity or by natural forces such as volcanic activity, species are the first to recolonize the site. Answer: pioneer 90) The stable community that tends to persist in an area after succession is known as the Answer: climax

community.

91) The rocks and weather that influence succession are examples of

factors.

Answer: abiotic 92) The productivity of an ecosystem usually

through succession.

Answer: increases 93) Succession in small ponds and lakes is usually dependent on the input of

from outside the ecosystem.

Answer: nutrients 94) When climax and subclimax vegetation combine in different parts of a(n) large number of plant and animal species.

, they provide habitats fora

Answer: ecosystem 95) Along many southern bayous, you can see the remnants of old plantations that have been reclaimed by the forest and swamp in a processknown as succession. Answer: secondary 96) Succession after a catastrophic disturbance such as a volcanic eruption is referred to as

succession.

Answer: primary 97) Succession after a disturbance such as forest harvest or a landslide is referred to as

succession.

Answer: secondary 98) What is the relationship between an ecosystem and a community? Answer: A community consists of all the interacting populations within an ecosystem. An ecosystem includes the abiotic environment as well as all plant and animal communities. 99) What factor most determines the intensity of interspecific competition? Answer: The degree of similarity between the competing species is the most important factor. 100) What effect does coevolution most likely have on niche overlap? Answer: Coevolution minimizes overlap. 101) What evidence did Gause and MacArthur find for the competitive exclusion principle? Answer: Gause displayed the competitive exclusion principle by putting two species of Paramecium with the same niche in a flask; as a result, the more adapted species survived and the less adapted one died. MacArthur observed that five North American warblers share an Eastern spruce tree for food and shelter and reduce competition by limiting overlap of their niches, demonstrating resource partitioning. 102) Antelope and kangaroos are both herbivores that feed on grasses and brush. What would you expect to happen if someone set up a game farm and released both species into the same grassy plain? Answer: Because both species eat the same foods, the competitive exclusion principle says that they cannot occupy the same niche in the community. One of two things will have to happen: One species will outcompete the other, leading to a reduction in its numbers and possible extinction from the habitat, or resource partitioning will occur, with each species limiting itself to a separate subgroup of plants in the ecosystem.

103) Many plants produce chemicals that are used as medicines. For example, the drug digitalis, which stimulates the human heart, is derived from foxglove, a poisonous plant. What advantage does producing toxic compounds have for the plant? Answer: In the plant, the compounds are poisons, which we use in small doses as medicines. The poisons protect the plant by making herbivores sick or killing them. 104) How might a predator use mimicry to its own advantage? Answer: A predator may resemble something attractive, such as food, so that prey will actively come to it. 105) There are several species of plain-looking, brownish-gray moths that, when they spread their wings, have large bright red or orange eye-shaped circles on their hind wings. What is this adaptation called, and what advantage does it give to themoth? Answer: This is startle coloration. It enables the moth to scare away an approaching predator at the same time that it flies away. 106) What distinguishes predators from parasites? Answer: Predators kill their prey, whereas parasites usually do not kill their host immediately; they keep the host alive so they can feed from it. 107) Kudzu is a vine that is native to Japan, but in the United States it is an exotic invader. In many parts of the United States, kudzu is rapidly expanding and outcompeting native species. Explain why kudzu is such an aggressive invader in the United States, but not in its native Japan. Answer: Because kudzu did not evolve in the United States, there are no native predators, parasites, or competitors that coevolved with it. Thus, kudzu found a niche that was unexplored, and other species are not keeping its population incheck. 108) Most bacteria can reproduce very quickly, so their populations increase rapidly. Describe the evolutionary process that prevents most human-disease-causing bacterial parasites from causing the human population to become extinct. Answer: Coevolution between parasites and their hosts favors selection for hosts that can survive infection (until after they have reproduced) and parasites that maintain their infectious capabilities. 109) You suspect that the American alligator is a keystone species in specific habitats in Florida. How could you experimentally prove or disprove this hypothesis? Answer: You could conduct removal experiments. If removal of the species in question dramatically alters the composition of the community, it was likely a keystone species. 110) How do organisms help to cause the changes that result in their own replacement in succession? Answer: Organisms change the physical environment in ways that favor their competitors. 111) What happens to the soil in an area as succession proceeds? Answer: The soil increases in depth and organic material content. 112) What kinds of plant species are likely to be pioneers in secondary succession? Explain why. Answer: Fast-growing annual weeds are likely to be pioneer species because they grow well in direct sunlight, their seeds are already present, and they are able to root in the soil that is already present.

113) After forest harvest in an old-growth forest of the Oregon Cascades, an ecologist noted that the species that were present after 5 years differed from the species that were present 25 years later, and these differed from the species that were present 75 years later. What are the general characteristics of the species at each stage, and why does the community change over time? Answer: This is an example of secondary succession. The first species to colonize the cleared site are generally fast-growing, easily dispersed, weedy species that are intolerant of shade. Fast-growing tree species eventually replace these weeds, and these in turn are replaced by shade-tolerant, slow-growing tree species that can outcompete the other species to form a relatively stable climax community. 114) Fire is increasingly used as a management tool in both forest and grassland ecosystems to increase species diversity. How might fire influence the occurrence of a climax community and species diversity? Answer: Fire can encourage the growth of subclimax plants that generally occurs earlier in succession. This diversity in the community's vegetation may also encourage greater animal diversity. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 115) The sea dragon in the illustration displays

A) chemical defenses. B) startle coloration. C) camouflage. D) warning coloration. E) aggressive mimicry. Answer: C

116) The caterpillar in the illustrationdisplays

A) warning coloration. B) camouflage. C) startle coloration. D) aggressive mimicry. E) chemical defenses. Answer: C

117) The succession shown in the illustration is A) primary. B) subclimax. C) biome. D) climax. E) secondary. Answer: A 118) In the illustration above, the shrubby blueberry and juniper are classified as a A) climax B) secondary C) biome D) primary E) subclimax

community.

Answer: E 119) Two species of buttercup are found in a field in North Dakota, and they tend to flower at approximately the same time in early spring. When some ecology students decided to conduct an experiment in community dynamics, they selectively removed one species from the field by hand-picking all emergent plants. The remaining species showed a significant increase in its population size during the next season. This study demonstrated A) habitat fragmentation. B) niche realignment. C) niche fragmentation. D) interspecific competition. E) intraspecific competition. Answer: D 18

120) On the slopes of the Washington Cascades, ecologists have studied some closely related vole species for decades. Many of these vole species, when they occur on separate mountains, tend to choose very similar seed sizes for food. However, when these species occur together on the same mountain slope, their food choices tend to differ, with some species selecting small seeds and others feeding exclusively on larger seeds. This behavior may be an example of A) niche fragmentation. B) intraspecific range diversion. C) intraspecific competition. D) habitat fragmentation. E) resource partitioning. Answer: E 121) In his 1961 paper "The Paradox of the Plankton," ecologist G. E. Hutchinson noted that several species of algae coexist, sharing the same few mineral nutrient resources in homogeneous open-water systems. Because there is little chance of resource partitioning and niche differentiation in such a situation, the paradox of their coexistence is an apparent violationof A) the climax theory of succession. B) Darwin's theory of evolution by means of natural selection. C) the law of mass action. D) the second law of thermodynamics. E) the competitive exclusion principle. Answer: E 122) In his study of the foraging behavior of bumblebees, D. W. Inouye noted that both Bombus appositus and Bombus flavifrons feed from both larkspur and monkshood flowers when each is the only bumblebee species present. However, when both species are present, B. appositus feeds on only larkspur and B. flavifrons feeds on monkshood. This behavior is an example of A) predation. B) resource partitioning. C) habitat fragmentation. D) aggressive mimicry. E) intraspecific competition. Answer: B 123) Several ecology students were tracking the population ranges of two species of squirrels that live in the Cascade Range of Oregon. These students noted that when both species of squirrels were present in a region, species A could be found from sea level to about 900 feet above sea level, and species B could be found from about 900 feet to 1,500 feet above sea level. However, when species B was found alone, it had a range of about 500 feet to 1,500 feet above sea level. This is an example of A) coevolution. B) parasitism. C) competitive exclusion. D) predator avoidance. E) habitat fragmentation. Answer: C

124) The tiny wasp Ooencyrtus kuvanae lays its eggs inside the egg masses of gypsy moths. When the wasp larvae hatch, they burrow into the gypsy moth caterpillars and eat them from the inside. After they have completed their development, the adult wasps emerge from the bodies of the moth caterpillars, killing them in the process. This relationship is classified as A) parasitism. B) coevolution. C) competition. D) predation. E) mutualism. Answer: A 125) Aphids pierce the tissues of plants with their tubular mouthparts and suck out the phloem juices. Because this food is mostly sugar water with a low concentration of protein, the aphids have to process large volumes of it to obtain sufficient protein. Most of the excess sugar and water passes right through the aphids' digestive tracts and is defecated as "honeydew," which is actively sought out and eaten by some ants. The ants will even "milk" honeydew by stroking the aphids. In return, ants protect their aphids from predators, even going so far as taking them inside overnight. The relationship between the aphids and ants is called A) parasitism. B) competition. C) mutualism. D) predation. Answer: C

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) What are the most basic components of all ecosystems? A) The living, or biotic part, and the abiotic B) Communities of organisms C) Nutrients and energy D) Volcanoes, wind, oceans, and other abiotic parts E) Producers, consumers, anddecomposers Answer: A 2) The atoms that make up the molecules in our bodies A) were all formed recently by nuclear fusion on the sun. B) were once part of adinosaur. C) will be lost back to space soon after we die. D) have nearly all been on Earth throughout its entire history. E) came from a wooly mammoth. Answer: D 3) What proportion of the solar radiation that reaches Earth's surface is visible light? A) Most of the radiation is absorbed by rocks on Earth's crust. B) A small fraction is visible light. C) About 90% of it is visible light. D) It is captured by plants and used in photosynthesis. E) About half is visible light. Answer: E 4) How much of the energy that reaches Earth's outer atmosphere from the sun is available for photosynthesis in plants at Earth's surface? A) 1% B) 44% C) 95% D) 71% E) 55% Answer: A 5) If a bird eats an insect that ate a plant, the bird is considered a(n) A) secondary consumer. B) tertiary consumer. C) primary consumer. D) producer. E) autotroph. Answer: A 6) A deer that gets its energy from eating plants is a(n) A) omnivore. B) carnivore. C) tertiary consumer. D) herbivore. E) producer. Answer: D

7) If a fox eats a rodent that ate a smaller insect that ate a plant, the fox is a(n) A) tertiary consumer. B) autotroph. C) secondary consumer. D) primary consumer. E) producer. Answer: A 8) The photosynthetic bacteria that form the basis of the food chain in the Great Salt Lake are classified as A) carnivores. B) omnivores. C) herbivores. D) producers. E) secondary consumers. Answer: D 9) If the plants in a community produce 500 grams of organic matter per square meter per year that is available for animals in the community to eat, this amount of energy is known as the A) consumership of the community. B) trophic factor of the community. C) availability factor of the community. D) net primary productivity of the community. E) secondary productivity of the community. Answer: D 10) The amount of life that an ecosystem can support is determined primarily by the A) number of heterotrophs. B) efficiency of the heterotrophs. C) efficiency of the consumers. D) number of producers and theirefficiency. E) number of chemoautotrophs. Answer: D 11) Organisms that must rely on complex, high-energy molecules produced by other organisms for survival are A) denitrifying bacteria. B) cyanobacteria. C) heterotrophs. D) producers. E) autotrophs. Answer: C 12) Which level of the energy pyramid has the greatest biomass? A) Secondary consumers B) Producers C) Primary consumers D) Carnivores E) Heterotrophs Answer: B

13) The first trophic level of an ecosystem consists of A) detritus feeders. B) secondary consumers. C) primary consumers. D) heterotrophs. E) producers. Answer: E 14) A carnivore is usually a(n) A) secondary producer. B) autotroph. C) primary producer. D) primary consumer. E) secondary consumer. Answer: E 15) The are an important and often overlooked group of organisms that release nutrients into the soil or water. A) decomposers B) heterotrophs C) tertiary consumers D) autotrophs E) producers Answer: A 16) The amount of energy lost as it passes from one trophic level to another is approximately A) 99%. B) 75%. C) 63%. D) 50%. E) 90%. Answer: E 17) If a field contains approximately 1,000 kilocalories of energy in grass, which is eaten by crickets, which are eaten by birds, then approximately how many kilocalories of energy could be in the birds that live in this field? A) 10 B) 100 C) 90 D) 1,000 E) 900 Answer: A 18) A carnivorous plant, such as a sundew, may be considered both a A) producer and a primary consumer B) primary consumer and a tertiary consumer C) primary consumer and a secondary consumer D) producer and a secondary consumer E) producer and a tertiary consumer Answer: E

when it eats a carnivorousspider.

19) The amount of energy captured by plants and made available to consumers in an ecosystem is called A) net primary productivity. B) secondary trophic level. C) nutrient cycling. D) biological magnification. E) energy pyramid. Answer: A 20) Certain bacteria and fungi that are important in nutrient recycling because they release nutrients from dead organisms back into theecosystem are A) decomposers. B) recyclers. C) carnivores. D) autotrophs. E) detritus feeders. Answer: A 21) Autotrophs gain energy from A) secondary producers. B) the sun and inorganic nutrients. C) omnivores. D) primary producers. E) secondary consumers. Answer: B 22) Net primary production is A) heterotrophic production per unit of land per unit of time. B) heterotrophic production minus autotrophic production per unit of land per unit of time. C) energy stored by secondary consumers from primary biomass. D) energy made by autotrophs minus energy consumed by heterotrophs, and measured as biomass. E) energy that photosynthetic organisms make available to other organisms over a given period of time. Answer: E 23) Which of the following terms correctly describes carnivores? A) Secondary consumers B) Autotrophs C) Consumer producers D) Primary consumers E) Detritus consumers Answer: A 24) Detritus feeders consume A) plants and plant debris. B) dead organic matter. C) secondary consumers and primary debris. D) herbivores. E) fungi and bacteria. Answer: B

25) A snake that eats a small rabbit that feeds on grass is classified as a(n) A) tertiary consumer. B) primary consumer. C) autotroph. D) secondary consumer. E) primary producer. Answer: D 26) In a grassland of Kansas, 1,000 grams of grass are produced per square meter per year by all the different grass species. A theoretical upper limit to the biomass of secondary consumers that can be supported in this ecosystem is A) 100 grams. B) 10 grams. C) 1 gram. D) 0.1 gram. E) 1,000 grams. Answer: B 27) In open-water marine ecosystems, the occupy the same trophic level as the giant sequoias (redwoods) in the forests of California. A) tiny, multicellular zooplankton ("animal drifters") that feed on phytoplankton B) microscopic, single-celled algae (protists) called phytoplankton ("plant-like drifters") C) fast-swimming, fish-eating tuna D) microscopic bacteria that decompose all the other organisms once they have died E) giant, squid-eating whales Answer: B 28) Bacteria that live in deep-sea thermal vents use energy from inorganic hydrogen sulfide (H2S) to make organic molecules from carbon dioxide and are thus A) producers. B) primary consumers. C) tertiary consumers. D) decomposers. E) secondary consumers. Answer: A 29) If you are attempting to minimize the amount of mercury in your diet, you should eat A) high-level carnivores such as tuna. B) omnivores such as hogs. C) producers such as fruits andvegetables. D) herbivores such as cattle. E) low-level carnivores such astilapia. Answer: C 30) Which trophic level has the LEAST biological magnification? A) Heterotrophs B) Primary producers C) Primary consumers D) Secondary consumers E) Tertiary consumers Answer: B 5

31) What is biological magnification? A) The breakdown of macromolecules into harmless substances B) The accumulation of toxic substances in a living organism C) An increase in the size of a population D) The process of making small living organisms larger E) The abnormal growth of organisms Answer: B 32) If a couple was attempting to get pregnant, which foods should they eat to avoid ingesting high amounts of toxins? A) Organic grains, fruits, and vegetables B) High-level carnivores such as tuna C) Meals microwaved in plastic bags D) High-fat salmon E) DDT-treated vegetables Answer: A 33) The community of detritivores, such as earthworms, millipedes, slugs, and pseudoscorpions, living in the leaf litter on the shady floor of a deciduous forest obtains its energy and nutrients primarily from A) decomposition of the leaves of deciduous trees that fall on the surface of the soil. B) chemosynthesis by green and purple sulfur bacteria living on the surface of the leaves. C) predation on one another. D) carbohydrates formed in the roots of the trees that leach out into the surrounding soil. E) photosynthesis or algae living in the soil beneath the leaves. Answer: A 34) In 1956, people in Minamata, Japan, began to exhibit severe neurological disorders and birth defects. This problem was eventually attributed to methylmercury, a water-insoluble and breakdown-resistant chemical formed from mercury dumped into the adjacent bay by a local factory. Which of the following types of seafood would have the highest levels of methylmercury, and therefore cause the severest effects? A) Krill (small crustaceans that eat tiny microscopic algae) B) Sea urchins that feed onkelp C) Tuna that feed on smaller fish that feed on krill that feed on algae D) Kelp (large, multicellular, photosynthetic protists) E) Mussels that feed on tiny microscopic algae Answer: C 35) The three major reservoirs of carbon are A) fossil fuels, legumes, and micronutrients. B) rocks, the atmosphere, and guano. C) oceans, the atmosphere, and fossilfuels. D) soil, water, and the atmosphere. E) acid precipitation, carbon-fixing bacteria, and oceans. Answer: C

36) Oceans, the atmosphere, and fossil fuels are large reservoirs of A) oxygen. B) carbon. C) nitrogen. D) phosphorus. E) water. Answer: B 37) Which of the following components is NOT involved in the phosphorus cycle? A) Some rocks and soil B) Decomposers C) The atmosphere D) Producers E) Consumers Answer: C 38) Which nutrient cycle lacks an atmospheric reservoir? A) Oxygen B) Nitrogen C) Carbon D) Water E) Phosphorus Answer: E 39)

is (are) a crucial nutrient reservoir of phosphorus that is available to organisms. A) Autotrophs B) Consumers C) Rocks D) The atmosphere E) Oceans Answer: C

40) Phosphorus, which is often a limiting nutrient in ecosystems, is important because it A) evaporates quickly. B) is part of the hydrologic cycle. C) is necessary for the production of cellulose so that autotrophs can grow and provide food for heterotrophs. D) is found only in sedimentary rocks. E) is needed for molecules such as adenosine triphosphate (ATP), cell membranes, and nucleic acids. Answer: E 41) The hydrologic cycle is different from other nutrient cycles in that A) water is not recycled, but flows one way through ecosystems. B) the ocean is involved. C) the biotic part of the cycle plays only a small role. D) the atmosphere is involved. E) the soil is notinvolved. Answer: C

42) Nitrogen is the most abundant element in the atmosphere, and a crucial component of proteins, vitamins, and nucleic acids. However, plants and other producers cannot use nitrogen in its natural form (N2). Nitrogen has to undergo a process called nitrogen fixation. What does this process involve? A) Ammonia is converted to nitrate. B) Nitrate is converted toammonia. C) It is the synthesis of ammonia from nitrogen gas by certain bacteria. D) It is undertaken by denitrifying bacteria. E) Nitrogen is accumulated indead organic matter. Answer: C 43) Micronutrients A) are smaller molecules than are macronutrients. B) are needed in smaller quantities than are macronutrients. C) benefit organisms if they are present but are not essential. D) are not naturally occurring and must be synthesized by scientists. E) include water, carbon, nitrogen, and phosphorus. Answer: B 44) Farmers often include legumes as part of their normal crop rotation. This practice increases the overall production of their crops by A) helping the soil retain water. B) making the soil less acidic. C) adding nitrogen to the soil. D) suppressing the growth of weeds. E) adding phosphorus to the soil. Answer: C 45) In an area with nitrogen-poor soil, legumes often dominate over other plants because they A) have long taproots that can extract nitrogen from deeper down in the soil. B) have unique access to the large atmospheric pool of nitrogen thanks to their symbiotic bacteria. C) inhibit the growth of denitrifying bacteria around their roots, thus keeping more nitrate in the soil. D) obtain supplemental nitrogen by trapping insects and other prey. E) do not need nitrogen at all. Answer: B 46) When nitrogen oxides and sulfur dioxide combine with water vapor in the air, they are converted to nitric acid and sulfuric acid, respectively. This precipitation that then falls to the Earth is known as A) acid deposition. B) acid precipitation. C) acid fog. D) nitrogen precipitation. E) decomposition acid. Answer: A

47) Phosphate fertilizers have increased the amount of phosphate in lakes and other bodies of water. What effect does this increase have on the phytoplankton in the water? A) It increases their likelihood of being eaten. B) It causes them to form toxic compounds. C) It reduces their photosynthetic capacity. D) It kills them. E) It stimulates their growth. Answer: E 48) Each summer, a large "dead zone" devoid of fish and other animals develops where the Mississippi River flows into the Gulf of Mexico. What causes this? A) High levels of pesticides are used in the Mississippi River basin. B) Acid rain makes the gulf's water too acidic to support fish. C) Global warming is making the river water too hot for the fish to tolerate. D) There are high levels of mercury in the river water. E) Large quantities of fertilizer run off from Midwestern farm fields into the Mississippi River. Answer: E 49) Acid deposition is the result of interference with the A) hydrologic and nitrogen B) sulfur and phosphorus C) sulfur and hydrologic D) sulfur and nitrogen E) hydrologic and phosphorus

cycles.

Answer: D 50) When you observe a lake that has been affected by acid deposition, you might expect to find A) low levels of toxic metals and nutrients essential for the growth of biotic organisms. B) excess carbon that will contribute to global warming. C) a clear lake with high levels of aluminum, mercury, and lead, but few fish. D) a murky lake with excess algal growth from the deposition of anthropogenic nitrogen. E) high levels of dissolved sulfur dioxide. Answer: C 51) The greenhouse effect, which has become a major ecological concern, is caused by A) global warming. B) the increase in atmospheric concentrations of greenhouse gases (CO2,CH4, and N2O). C) the destruction of ozone in the upper atmosphere. D) the release of heat energy from burning fossil fuels. E) overuse of fertilizers in farming. Answer: B 52) Why is the concentration of carbon dioxide in Earth's atmosphere rapidly increasing? A) Many human activities release carbondioxide. B) More photosynthesis is occurring. C) The oceans are cooling. D) Earth is warming. E) The ozone layer has become much thinner. Answer: A

53) Carbon dioxide and other greenhouse gases cause Earth's temperature to increase by A) increasing the amount of radiation from Earth's surface. B) absorbing heat energy and holding it close to Earth. C) allowing greater transmission of incoming solar radiation. D) increasing plant respiration. E) reducing photosynthetic rates. Answer: B 54) Burning coal and oil to release energy also releases A) sulfur, carbon, and nitrogen B) nitrogen, phosphorus, and potassium C) oxygen, methane, and sulfur D) sulfur, oxygen, and acid E) phosphorus, carbon, and nitrogen

, which are overloading Earth's nutrient cycles.

Answer: A 55) What are the sources of sulfur in the atmosphere? A) Mostly transportation modes, such as autos, trucks, and planes B) Decomposition and small amounts from pollution C) Mostly (over 90%) volcanoes and photosynthetic bacteria D) Volcanoes and hot springs, but mostly (about 75%) human activities such as burning coal E) Natural and human sources, in equal amounts Answer: D 56) Human-caused disturbances of the A) oxygen B) phosphorus C) hydrologic D) sulfur E) carbon

cycle may be contributing to global warming.

Answer: E 57) The greenhouse effect is the ability of A) certain gases to absorb solar heat and reflect the heat to Earth as short-wave radiation. B) certain gases to retain heat in the atmosphere instead of allowing it to be reflected back into space. C) sulfur dioxide and nitrogen oxides to retain heat in the upper atmosphere. D) sulfur dioxide and nitrogen oxides to retain heat in the lower atmosphere. E) structures created by humans to retain solar energy as short-waveradiation. Answer: B 58) The present range of the sugar maple in North America extends from the Atlantic Ocean west to the Mississippi River and from southern Ontario, Quebec, and New Brunswick south to Tennessee and Virginia. If the global temperature rises 10°C in the future, where will the range of sugar maples be found? A) Farther north B) Farther west C) Farther south D) In the same place; global warming will not affect the heat tolerance of plants. E) Nowhere; sugar maples will become extinct. Answer: A

59) Forests along rivers in the Pacific Northwest that have lost their salmon populations are less productive because the A) pollution that killed the fish has also directly affected the trees. B) nitrogen the fish brought from the ocean and contained in their tissues has been lost. C) fishers who overharvested the salmon compacted the soil in the process. D) dams that prevented the fish from migrating also flooded the forests. E) global warming that wiped out the fish has also harmed the trees. Answer: B 60) Once used by an organism, carbon- and nitrogen-based nutrients are unavailable for other organisms. A) True B) False Answer: B 61) The primary source of Earth's energy is the sun. A) True B) False Answer: A 62) Organisms that produce their own food from inorganic compounds through reactions powered by sunlight are heterotrophs. A) True B) False Answer: B 63) Autotrophs use solar energy to build their own complex organic molecules from inorganic compounds such as water and carbon dioxide. A) True B) False Answer: A 64) Horses and cows are primaryconsumers. A) True B) False Answer: A 65) Iron is a limiting factor in many aquatic ecosystems. If the iron level is increased, the amount of phytoplankton (which feed on iron) decreases. A) True B) False Answer: B 66) The primary consumers in marine food chains are phytoplankton. A) True B) False Answer: B

67) Detritus feeders remove nutrients from the food chain. A) True B) False Answer: B 68) When a rabbit eats the lettuce in your garden, the rabbit uses all of the energy in the lettuce. A) True B) False Answer: B 69) The level of environmental toxins such as DDT decreases as you move into the higher trophic levels. A) True B) False Answer: B 70) Macronutrients are elements or small molecules that are needed in only trace amounts. A) True B) False Answer: B 71) Aquifers are underground reservoirs in the hydrologic cycle. A) True B) False Answer: A 72) Plants absorb small amounts of carbon from the soil in the form of simple sugars or monosaccharides. A) True B) False Answer: B 73) Fossil fuels are the major reservoir in the phosphorus cycle. A) True B) False Answer: B 74) Plants often grow poorly in sterilized soils because the soils lack nitrogen-fixing bacteria. A) True B) False Answer: A 75) The major reservoir in the nitrogen cycle is the water. A) True B) False Answer: B 76) Burning high-sulfur coal increases aciddeposition. A) True B) False Answer: A

77) Deforestation decreases the levels of greenhouse gases in the atmosphere. A) True B) False Answer: B 78) Carbon dioxide is the only greenhouse gas. A) True B) False Answer: B 79) Many climatologists blame the recent extremes in weather on global warning. A) True B) False Answer: A SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 80) One of the basic principles of ecosystems is that one-way flow.

moves through the ecosystems in a continuous

Answer: energy 81) One of the basic principles of ecosystems is that

cycle within the ecosystems.

Answer: nutrients 82) Herbivores occupy the trophic level of

consumer.

Answer: primary 83) Grasses and phytoplankton are

Answer: producers, or autotrophs 84)

are organisms such as earthworms, millipedes, and other scavengers that eat waste products and dead organic matter. Answer: Detritivores

85) Organisms that produce their own food in photosynthesis are known as producers, or

("self-feeders").

Answer: autotrophs 86) Bacteria and fungi that secrete enzymes into the surrounding environment to break down wastes and dead organic matter are . Answer: decomposers 87) In the

cycle, water is cycled among the atmosphere, oceans, and living organisms.

Answer: hydrologic 88) The primary reservoir for the nutrient

is rock.

Answer: phosphorus 89) The global hydrologic cycle begins with precipitation falling to Earth, and the cycle is completed by driven by solar energy. Answer: evaporation 13

90) The primary cause of the current increase in levels of atmospheric CO2 is the burning of

by humans.

Answer: fossilfuels 91) Ornithologists have noted that Mexican Jays in Arizona are nesting 10 days earlier in the springtime today than they did in the 1970s. They suggest that this behavior is evidence of . Answer: global warming, or climate change 92) Your emit.

is a measure of your impact on the environment based on the amount of greenhouse gases you

Answer: carbon footprint 93) What would happen in an ecosystem without decomposers and detritus feeders? Answer: Wastes would accumulate, nutrient cycles would slow or stop, and soil quality would deteriorate. 94) What would happen to an ecosystem if all the plants died? Answer: Oxygen levels would quickly decrease, and food production would eventually stop. 95) Suppose a gardener puts a chemical on the soil that kills off all the detritus feeders and decomposers. What would happen to the garden? Answer: Nutrients could not be recycled, leaf litter would accumulate, and the productivity of the garden would drop. 96) Explain how the world's food supply may be affected by whether people eat primarily meat or vegetables. Answer: If people eat plant materials, approximately 90% more food is available to them than if they eat meat (the "10% law"). 97) What is meant by the term trophic level? Answer: A trophic level is a feeding level of organisms in a food chain. 98) Tropical rain forests are near the equator; they stay warm all year and have high annual precipitation. Northern coniferous forests have four seasons and most of the precipitation falls during winter and spring. Which of these ecosystems would you expect to be more productive? Explain why. Answer: Tropical rain forests are more productive because the abundance of resources such as light and moisture allows for greater primary productivity. 99) Explain why a food web gives a better picture of a community than does a food chain. Answer: A food web portrays the interactions among organisms in which many organisms eat from more than one level. 100) Explain why decomposers and detritus feeders are so important to ecosystems. Answer: They recycle nutrients to simple molecules that are returned to the abiotic environment for use again by plants and then are passed on to animals, thus maintaining the ecosystem. 101) If you were a researcher trying to design a pesticide that would not accumulate by biological magnification, what two properties should the pesticide have? Answer: It should break down quickly into harmless compounds, and it should be easily excreted.

102) There is a school of thought that encourages humans to give up eating meat and become herbivores. What are the advantages to this? Answer: By eating lower on the food chain, a person is making better use of the energy (less energy is lost in moving between trophic levels) and there is less bioaccumulation. 103) Why might eating high on the food chain subject humans to higher concentrations of certain toxic substances than eating low on the food chain? Answer: Biological magnification means that there are higher concentrations of certain compounds in higher trophic levels. 104) Plants produce biomass by taking in energy, CO2, and nutrients from the environment; consumers eat much of this biomass, but not all. However, ecosystems do not indefinitely accumulate large quantities of organic matter over time. Why not? Answer: When consumers eat plant organic matter, much of the carbon is respired, and the nutrients are returned to the soil. Decomposers also recycle much of the remaining organic matter. Many ecosystems do accumulate organic matter, but not indefinitely. 105) Nitrogen is fixed by soil bacteria and is then incorporated into plant biomass and eventually into the food chain. What process(es) complete the global nitrogen cycle? Answer: Decomposers turn the nitrogen in dead plant and animal bodies into soluble forms of nitrogen in soil or water; denitrifying organisms convert these soluble inorganic forms of nitrogen into gaseous forms of nitrogen that enter the atmosphere. 106) Plants cannot fix nitrogen, but legumes are often called nitrogen fixers. Explain why this label is appropriate. Answer: Legumes have a mutualistic relationship with nitrogen-fixing bacteria in nodules in legume roots. 107) What would happen if there were no denitrifying bacteria? Answer: The atmosphere would have less nitrogen gas available for nitrogen fixation. 108) Why is phosphorus so important to living organisms? Answer: In the form of phosphate, phosphorus is a component of ATP, NADPH, DNA, RNA, and phospholipids as well as bones andteeth. 109) The global phosphorus cycle is called a "cycle," yet it has no atmospheric component. Phosphorus weathers from rocks and enters the soil. Once phosphorus is incorporated into plants or animals, how is it returned to the rock phase? Answer: Decomposers return the phosphorus from dead animal and plant bodies back to the soil, where it combines chemically with water to form phosphates; it may then be bound into sediment and eventually reincorporated into rock through geologic activity. 110) Why is acid rain or acid deposition more of a problem in certain areas, such as New England, than in others? Answer: Prevailing winds carry nitrogen oxides and sulfuric acid to New England, where they combine with water vapor in the atmosphere to form nitric acid and sulfuric acid. The rocks and soils in New England are unable to neutralize the acid. 111) List and discuss three effects of acid rain or acid deposition on forests. Answer: Possible answers: Acid rain (1) leaches essential nutrients such as calcium and potassium; (2) kills decomposer microorganisms; (3) makes plants weaker and more subject to infection; (4) makes plants more subject to attack by insects; and (5) causes plant roots to shrink.

112) Sulfur dioxide is a natural product of volcanoes and hot springs, and by itself, it is not acidic. How, then, is excess sulfur dioxide linked to acid rain or acid deposition? Answer: When it combines with water vapor in the atmosphere, sulfur dioxide is converted into sulfuric acid, which returns to Earth in precipitation or as particulates. Human industrial activities account for 90% of the sulfur dioxide that is emitted into the atmosphere. 113) On a field trip with your class to mountain lakes in Vermont, you come across a beautiful clear lake that is deep, and you can see the pebbles at its bottom. Why does your classmate hypothesize that this lake has been subjected to acidic deposition? Answer: The lake is clear because all plants, algae, and aquatic organisms are dead. 114) Why is it so hard to make definite predictions about the amount and timing of global warming as a result of greenhouse gases? Answer: So many factors are interacting that it is difficult to know how all of them will respond to rising levels of greenhouse gases. 115) It has been said about global warming that "one human in a developed country is not equivalent to one person in a developing country." What does this statement mean? Answer: Each individual in a developed country produces many times more greenhouse gas emissions than an individual in a developing country. With less than 5% of the world's population, Americans are responsible for more than 20% of the world's greenhouse emissions. 116) What are some possible consequences of global warming? Answer: The models that predict the effects of global warming anticipate a rise in sea level, shifts in temperature and rainfall patterns, alteration of range and species composition of forests, and changes in ocean currents.

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 117) A rancher begins raising sheep on the land next to the habitat shown. After losing several lambs, he removes all the wolves. By the next year, he can expect to find a(n)

A) decreased pheasant population. B) decreased antelope population. C) increased hare population. D) decreased owl population. Answer: C

118) According to the data presented in the graph, between 1960 and 2000, CO2 levels rose approximately ppm.

A) 20 B) 370 C) 50 D) 320 E) 70 Answer: C 119) This graph, which is based on estimates from the International Panel on Climate Change (IPCC), shows that by 2100, global temperatures may rise as much as above average levels in 2000. The dashed data line represents a high growth of greenhouse gas, the dotted data line represents a moderate growth of greenhouse gas, and the square data line represents a substantially reduced growth of greenhouse gas.

A) nearly 4°C B) 2.5°C C) nearly 2°C D) 1°C E) 3°C Answer: A

120) The graph indicates that since 1960, global average temperatures have

A) remained constant. B) initially increased but are nowdropping. C) only decreased. D) only increased. E) fluctuated but risen overall. Answer: E 121) As part of a research project, a graduate student creates an artificial environment in a sealed container. She sterilizes the soil and adds plants, snails, shrews, and a snake. After adding a small artificial pond, she seals the container. During the first several weeks, the plants are thriving and the animals are doing well. However, piles of dropping are beginning to accumulate, and the entire floor of the container becomes covered with a layer of plant debris several inches thick. One probable cause for the problems is that the graduate student didn't A) put in enough plants. B) include any herbivores. C) add any decomposers. D) include any carnivores. E) include any autotrophs. Answer: C 122) In an attempt to become more environmentally conscious, a woman changes her lifestyle. She begins to grow the majority of her own food in her yard without using pesticides or synthetic fertilizers, she walks rather than taking the car for trips shorter than 5 kilometers, and she uses solar and wind for her power. By taking these actions, she is A) increasing the number of endocrine disruptors to which she is exposed. B) increasing her intake of bioaccumulated compounds. C) increasing her greenhouse gas output. D) increasing her nitrogen cycling. E) decreasing her carbonfootprint. Answer: E

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) What is the role of the ozone layer? A) It increases the gyres. B) It reduces the amount of UV light that reaches Earth's surface. C) It increases photosynthesis in Antarcticphytoplankton. D) It increases the amount of sunlight that reaches the poles. E) It increases the levels of chlorofluorocarbons (CFCs) in the upper atmosphere. Answer: B 2) The temperatures at the equator remain warm year round because A) sunlight strikes the equator relatively directly with little seasonal variation. B) there are large oceans near the equator that absorb large amounts of heat. C) Earth's rotation on a tilted axis creates more atmospheric friction at the equator. D) Earth's natural curvature places the equator nearer to the sun. E) the sun shines longer over the equator than it does over other parts of Earth. Answer: A 3) The prevailing winds in the Glacier National Park area of Montana are from the west. Which side of this mountainous region receives the most rain and snow? A) East B) North C) South D) West E) It depends on the season. Answer: D 4) A(n) is an area that is very dry because the air in that region has passed over a mountain and lost most of its moisture. A) rain shadow B) basin C) tropical desert D) chaparral E) adiabat Answer: A 5) A rain shadow is causedby A) warm, moist air that cools as it moves down over a mountain, releasing moisture. B) large mountain masses in the center of continents that restrict air flow. C) ocean currents that heat and cool more slowly than do air or landmasses. D) ocean currents that heat and cool more quickly than do air or landmasses. E) cool, dry air that warms as it moves down over a mountain, picking up moisture. Answer: E 6) Maintaining the ozone layer is crucial for life because ozone A) blocks high-energy infrared radiation. B) absorbs visible light. C) absorbs high-energy UV radiation. D) absorbs low-energy UV radiation. E) blocks low-energy infrared radiation. Answer: C

7) Earth's ozone layer is extremely important because it A) traps harmful infrared rays. B) maintains high carbon dioxide concentrations so that photosynthesis can occur. C) blocks incoming visible light to protect Earth against the greenhouse effect. D) traps heat so that Earth's temperature does not fall too much. E) blocks incoming UV radiation, which is damaging to animals and reduces photosynthesis in plants and algae. Answer: E 8) The destruction of the ozone layer is caused by a chemical reaction between UV light and A) hydrogen sulfide. B) nitrogen. C) chlorofluorocarbons (CFCs). D) helium. E) methane. Answer: C 9) The ozone hole over Antarctica and the general lowering of ozone levels elsewhere in the stratosphere have been attributed to the ozone-destroying properties of A) carbon dioxide and methane. B) nitrogen oxides. C) chlorofluorocarbons (CFCs). D) endocrine-disrupting chemicals. E) sulfur dioxide. Answer: C 10) Why do higher-latitude ecosystems experience more pronounced seasons than ecosystems at equatorial latitudes? A) Earth is tilted on its axis as it orbits the sun annually. B) Air currents generated by Earth's rotation have stronger effects at higher latitudes. C) The mass of the continents is greater at the equator, which evens out temperature variations in ocean circulation. D) Heated air rises at the equator and falls at mid-latitudes. E) Ocean currents moderate near-shore environments. Answer: A 11) The primary driving force behind winds, ocean currents, and the global water cycle is A) geothermal heating from beneath Earth'ssurface. B) Earth's magnetic field. C) heat produced by the sun. D) the gravitational pull of the moon. E) Earth's rotation. Answer: C 12) What are the fundamental resources required to support life? A) Nutrients, oxygen, sugar, appropriate temperatures B) Oxygen, carbon, nitrogen, water C) Water, energy, oxygen, nutrients D) Oxygen, water, energy, carbon E) Water, nutrients, energy, appropriate temperatures Answer: E

13) The thick, green stems and spike-like leaves of cacti and other drought-resistant bushes are adaptations to A) conserve water in dry environments. B) collect light in environments that have limited amounts of light. C) increase gas exchange in oxygen-poorenvironments. D) take up atmospheric nitrogen in nutrient-poorenvironments. E) speed up heating and cooling in environments that have little temperature fluctuation. Answer: A 14)

are large areas that have similar environmental conditions and characteristic plant communities. A) Climax communities B) Ecosystems C) Biomes D) Climatic zones E) Biospheres Answer: C

15) The greatest diversity of plants and animals is found in A) temperate deciduous forests. B) tropical rain forests. C) northern coniferous forests. D) chaparrals. E) savannas. Answer: B 16) In a tropical rain forest, the majority of animals are found A) in the cleared areas. B) in the towering treetops. C) in the shorter trees. D) on the forest floor. E) in the soil. Answer: B 17) Which of the following North American biomes has been almost completely destroyed by agricultural use? A) Northern coniferous forest B) Grassland C) Temperate deciduous forest D) Desert E) Tundra Answer: B 18) Why do most of the flowers in a temperate deciduous forest bloom in the spring? A) Nutrients are most available in the spring. B) The largest number of insect pollinators is available in the spring. C) In the spring, the trees do not block the wind and thus do not prevent wind pollination. D) The spring is the dry season; most of the rain falls during the cool, wet winters. E) The leaves of deciduous trees do not block the light in the spring; therefore, sunlight reaches the forest floor. Answer: E

19) In the fall, the trees in a temperate deciduous forest lose their leaves primarily as an adaptation to A) lack of accessible nutrients. B) cooler temperatures. C) changing light. D) excess rainfall. E) lack of available water. Answer: E 20) A(n) is a cold region with evergreen coniferous trees as the dominant vegetation. A) tundra B) arctic C) northern coniferous forest D) chaparral E) savanna Answer: C 21) What is the dominant vegetation of the savanna? A) Cocoa B) Lichens and scrub willows C) Trees with waxy needles D) Trees that lose their leaves E) Grasses Answer: E 22) The vast treeless region near the Arctic Ocean is the A) northern coniferous forest. B) grassland. C) tundra. D) permafrost. E) savanna. Answer: C 23) Permafrost is associated with which of these biomes? A) Northern coniferous forest B) Grassland C) Littoral D) Tundra E) Temperate deciduous forest Answer: D 24) The striking dissimilarities in plant communities among different biomes that have the same average yearly amount of rainfall can be explained by the fact that A) plant communities evolve more slowly than changes in weather patterns. B) plant communities are not influenced by rainfall. C) plant communities occur randomly, depending on where seeds are blown or carried. D) plant communities are influenced more by the acidity of rain than by the amount of rainfall. E) temperature and rainfall interact to influence plant communities. Answer: E

25) The northern coniferous forest is characterized by A) few grasses, moist soils, and trees that drop their leaves in the winter. B) dry soils that lack vegetation. C) long and cold winters, short growing seasons, and conifers. D) fire-adapted plants. E) tallgrass. Answer: C 26) If global warming makes the southeastern United States warmer but does not change the amount of rainfall, we might expect to see a shift from the present temperate deciduous forest biome to A) tropical rain forest. B) tropical deciduous forest. C) alpine tundra. D) northern coniferous forest. E) chaparral. Answer: B 27) Native Americans were able to prevent the encroachment of trees and maintain the tallgrass prairies by A) clear-cutting the forests for timber and fuel. B) setting fires periodically to kill the trees. C) restricting the migrations of bison, which caused the bison to browse heavily on tree seedlings and thus kill them. D) establishing an extensive irrigation system to increase soil moisture, thus favoring grasses. E) plowing much of the land for agriculture. Answer: B 28) Which biome probably contains the largest number and most diverse group of large mammals? A) Tropical rain forest B) Desert C) Chaparral D) Tropical deciduous forest E) Savanna Answer: E 29) Plants in this biome have small leaves coated with protective waxes to reduce evaporation, and they can survive a fire. A) Tropical rain forest B) Desert C) Chaparral D) Savanna E) Tropical deciduousforest Answer: C 30) In which biome would you expect to find large numbers of black bears, snowshoe hares, moose, lynx, wolves, and deer? A) Northern coniferous forest B) Tropical rain forest C) Desert D) Chaparral E) Savanna Answer: A

31) Pronounced wet and dry seasons and warm year-round temperatures are characteristic of A) tropical rain forests. B) chaparrals. C) tropical deciduous forests. D) deserts. E) tundras. Answer: C 32) Which biome is rapidly expanding into the African Sahel? A) Tropical deciduous forest B) Chaparral C) Desert D) Savanna E) Tropical rainforest Answer: C 33) Which biome receives the lowest annual rainfall? A) Savanna B) Tropical deciduous forest C) Desert D) Chaparral E) Tropical rainforest Answer: C 34) Thick, water-storing leaves and stems and shallow, spreading roots are adaptations to A) deserts. B) northern coniferous forests. C) tropical scrub forests. D) temperate deciduous forests. E) tropical rainforests. Answer: A 35) Which biome is characterized by widely spaced trees surrounded by grasses? A) Tropical deciduous forest B) Savanna C) Tropical rain forest D) Chaparral E) Desert Answer: B 36) Multiple layers of vegetation, ranging from shade-tolerant undergrowth to towering sun-loving canopy trees, are characteristic of A) savannas. B) chaparrals. C) tallgrass prairies. D) deserts. E) tropical rainforests. Answer: E

37) What are the major limiting factors that determine the distribution of organisms in aquatic ecosystems? A) Appropriate temperatures and excess water B) Availability of water and appropriate temperatures C) Excess water and nutrients D) Light and nutrients E) Light and excesswater Answer: D 38) In aquatic ecosystems, the highest nutrients levels are found in areas that have the A) highest light levels. B) highest elevation. C) lowest light levels. D) highest temperatures. E) fewest sediments. Answer: C 39) The is the zone near the shore of a lake where a diverse group of organisms lives and where light and nutrients are abundant. A) littoral B) profundal C) stratification D) phytoplankton E) limnetic Answer: A 40) Oligotrophic lakes are characterized by A) the largest number and diversity of organisms. B) low oxygen concentrations. C) dense "blooms" of algae. D) low nutrient levels, and clear water with deep penetration of light. E) high nutrient levels, murky water, and shallow penetration of light. Answer: D 41) The profundal zone is home to organisms that are A) photosynthetic. B) decomposers and detritivores. C) adapted to high levels of light. D) intertidal. E) eutrophic. Answer: B 42) Coral reefs have formed as the result of A) rising ocean levels. B) seafloor settling. C) skeletons from some types of Cnidarians and algae. D) cool water settling over warmerwater. E) volcanic activity in warm tropical waters. Answer: C

43) Which zone is inhabited by bottom-feeding catfish, crayfish, aquatic worms, clams, and bacteria? A) Intertidal B) Limnetic C) Profundal D) Pelagic E) Benthic Answer: C 44) In the unique seafloor vent community, the primary producers are A) tube worms. B) sulfur bacteria. C) phytoplankton. D) giant snails. E) plants. Answer: B 45) In hydrothermal vent communities, primary productivity is based on A) bacterial decomposition. B) chemosynthesis. C) detritivores D) herbivory. E) photosynthesis. Answer: B 46) What is the ecological significance of shallow bays and coastal wetlands such as estuaries and salt marshes? A) They are the breeding grounds for a wide variety of sea-dwelling animals. B) Coral reefs occur in theseareas. C) They are safe from most human impact because humans do not live there. D) They are an important source of crude oil. E) They serve as the habitat for many endangered species. Answer: A 47) Why is the human-caused damage to coral reefs of particular concern? A) Reefs are not particularly sensitive to human-caused disturbance. B) Reefs represent unique ecosystems that obtain energy through chemosynthesis rather than photosynthesis. C) Reefs function in the detoxification of marine pollutants. D) The physical structure of reefs has an important influence on the movement of ocean currents. E) Reefs provide food and shelter for the world's most diverse collection of marine invertebrates and fish. Answer: E 48) The major concentrations of life in the oceans are found in A) deep, large oceans due to high nutrient concentrations. B) the anoxic zone. C) the oligotrophic zone due to clear and clean water. D) regions of upwelling and in shallow coastal waters. E) the aphotic zone due to high light levels. Answer: D

49) One consequence of global warming is the melting of the glaciers and the resulting rise in sea levels. What will likely be the direct effect of this increase in sea levels on coral reefs? A) Productivity will increase as the pure water from the glaciers dilutes the nutrients in the sea. B) Coral reefs will be stimulated to grow faster due to the dilution of the seawater's salt content. C) Coral reefs in shallow waters will grow more rapidly due to added protection against harmful UV radiation. D) Productivity will decrease as nutrients trapped in the glacial ice are released and spread throughout the oceans by currents. E) Coral reefs in deeper waters will die because insufficient light reaches them for photosynthesis. Answer: E 50) The most heat-tolerant organisms presently known come from A) deep-sea hydrothermal vents. B) chaparrals. C) tundras. D) tropical rain forests. E) tropical deciduousforests. Answer: A 51) The Atlantic cod population decreased dramatically during the 1900s due to overfishing. What conservation measure, presently being applied, is most likely to help this fish population recover? A) Putting a bounty on sharks and tuna in the area that would otherwise eat the cod B) Fertilizing the ocean with raw sewage to cause eutrophication, thus increasing productivity C) Establishing marine reserves in the area that prohibit fishing until stocks recover D) Spreading silt in the water to reduce UV radiation damage to sensitive cod eggs E) Encouraging selective fishing on haddock, turbot, and other species that compete with cod for food Answer: C 52) Why do areas of upwelling tend to have large and diverse populations of organisms? A) Upwelling moves dinoflagellates to the aphotic zone. B) Upwelling mixes deep-ocean fresh water with salt water from rivers. C) Upwelling brings nutrient-rich water up from the ocean depths. D) Upwelling lowers the level of oxygen in the water. E) Upwelling brings aphotic organisms to the ocean surface. Answer: C 53) The producers in hydrothermal vent communities are A) kelp. B) zooplankton. C) sulfur bacteria. D) coral. E) phytoplankton. Answer: C 54) Oligotrophic lakes A) provide breeding grounds for many fish and crustacean species. B) remove nutrient-rich sediments from fieldrunoff. C) support dense plant communities. D) have low levels of nutrients and few organisms. E) depend on sulfur bacteria as the primary producers. Answer: D

55) Which area contains aquatic organisms that can tolerate exposure to air? A) Twilight region B) Coral reefs C) Ocean floor D) Intertidal zone E) Aphotic zone Answer: D 56) Patterns of temperature and precipitation that prevail over years are referred to as weather. A) True B) False Answer: B 57) Seasonal variations in temperature are due to the tilt of Earth on its axis. A) True B) False Answer: A 58) The Atlantic Ocean gyre moderates the climate of the eastern coast of North America by bringing in warm currents from the equator. A) True B) False Answer: A 59) The windward side of a mountain range has the drier climate because of the rain shadow. A) True B) False Answer: B 60) Plants with small leaves and thick stems that store water are more likely to be found growing in a rain shadow. A) True B) False Answer: A 61) Plant life in the different biomes is limited only by the amount of sunlight. A) True B) False Answer: B 62) The highest biodiversity is found in temperate deciduous forests. A) True B) False Answer: B 63) The defining characteristic of a desert is the high temperature. A) True B) False Answer: B

64) Rain-forest soils store large amounts of nutrients, which makes them ideal for farming. A) True B) False Answer: B 65) Savannas are tropical regions characterized by scant, seasonal rainfall that supports grasses and a few drought-resistant trees. A) True B) False Answer: A 66) The loss of native vegetation to overgrazing, overharvesting, and overuse of groundwater to grow crops can lead to desertification. A) True B) False Answer: A 67) Desert wildflowers typically bloom in late summer. A) True B) False Answer: B 68) In temperate deciduous forests, trees drop their leaves in response to reduced sunlight. A) True B) False Answer: B 69) Northern coniferous forests, characterized by long, cold winters and conifers with short needles, are the largest terrestrial biome. A) True B) False Answer: A 70) In the temperate rain forest, the establishment of new tree seedlings is limited by the lack of light reaching the forest floor. A) True B) False Answer: A 71) Eutrophic lakes have high nutrient levels and dense plant communities. A) True B) False Answer: A 72) Wetlands remove toxins, pesticides, and sediments from water, acting as a natural water purifier. A) True B) False Answer: A

73) Channeling rivers improves their productivity and decreases erosion. A) True B) False Answer: B 74) Estuaries have very low bioproductivity and diversity. A) True B) False Answer: B 75) The deep ocean floor doesn't have enough light to support any producers. A) True B) False Answer: A SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 76) The destruction of the

layer increases the amount of damaging UV light that reaches Earth's surface.

Answer: ozone 77) A

is a circular ocean current caused by wind and the presence of continents.

Answer: gyre 78) During summer, the Northern Hemisphere tilts

the sun because of Earth's curvature and tilted axis.

Answer: toward 79) In the Southern Hemisphere, gyres rotate in the

direction.

Answer: counterclockwise 80) As air travels over a mountain range, it warms on the far side and absorbs water from the land, creating a local dry area called a . Answer: rain shadow 81) Weather patterns that occur over years or centuries in a particular region make up its

Answer: climate 82) A region that has grasses as the dominant vegetation form, widely spaced trees, a short wet season, and a pronounced dry season is a . Answer: savanna 83)

are large-scale communities in which the vegetation is determined by long-term patterns of temperature and precipitation. Answer: Biomes

84)

trees drop their leaves in response to decreased water availability. Answer: Deciduous

85)

is the year-round layer of frozen soil that limits the growth of trees and other deep-rooted plants in the arctic tundra. Answer: Permafrost 12

86)

of timber for lumber and paper has severely damaged the northern coniferous forest. Answer: Clear-cutting

87) A biome that is characterized by an annual rainfall of 10 inches or less is called a

Answer: desert 88) In the tropical deciduous forest, the amount of

defines the seasons.

Answer: rainfall 89) The

zone of an open-water lake receives enough light to support photosynthesis.

Answer: limnetic 90) Reef-building corals enter into a mutually beneficial relationship with photosynthetic protists called as a means of obtaining food. Answer: dinoflagellates 91) On the basis of nutrient content, a mountain lake with little sediment or nutrients is classified as a(n) lake. Answer: oligotrophic 92) On the basis of nutrient content, a lake that has received large amounts of runoff from farms, feedlots, or sewage is classified as a(n) lake. Answer: eutrophic 93) The shallow, near-shore region of large lakes that supports the greatest diversity of plant and animal life is the zone. Answer: littoral 94) In the open-water region of freshwater lakes, the organisms.

zone lacks sufficient light for photosynthetic

Answer: profundal 95)

are flat lands surrounding rivers that are covered with nutrient-rich sediments when water overflows the banks. Answer: Floodplains

96) Why are mountaintops colder than valley bottoms? Answer: The atmosphere is thinner and retains less heat at higher elevations. 97) What factors determine the patterns of ocean currents? Answer: The patterns are determined by Earth's rotation, wind, heating by the sun, and the presence of continents. 98) Explain why there are enormous deserts in the area of the United States known as the Great Basin, which is east of the Sierra Nevada Mountains and west of the Rockies. Answer: The air coming off the Pacific Ocean is pushed up over the Sierras, where it drops its moisture. As the air drops back to lower elevations, it warms, creating dry, warm air over the Great Basin.

99) The weather at the equator is both fairly constant seasonally and quite warm. What physical factors of Earth's position relative to the sun are responsible for these characteristics? Answer: At the equator, sunlight hits Earth's surface at nearly a right angle, whereas farther north or south the sun's rays strike Earth's surface at a greater slant, spreading the same amount of sunlight over a greater area. Also, Earth is tilted on its axis, so higher latitudes experience considerable variation in the directness of the sunlight throughout the year. 100) Western Oregon generally has cooler summer temperatures and warmer winter temperatures than do same-latitude states that are inland; similarly, Cape Cod (a coastal peninsula southeast of Boston) generally has a more moderate climate than interior Massachusetts does. Why? Answer: Because water both heats and cools more slowly than does land or air, ocean currents tend to moderate temperature extremes. Consequently, coastal areas tend to have less variable climates than do areas near the center of continents. 101) List one of the two geographical characteristics of most deserts. Answer: The two characteristics are their location at approximately 30° N and 30° S latitudes and in the rain shadow of large mountain ranges. 102) Explain why climate is the primary factor determining the type of ecosystem in an area. Answer: Climate is determined by sunlight, water, and temperature, which are three of the four basic requirements for life. Thus plants with similar requirements tend to be found in areas with similar climate. 103) Explain why it would probably be a money-losing venture to establish a plantation to grow corn in an area that used to be tropical rain forest. Answer: The soil is infertile because the nutrients are tied up in the vegetation. What few nutrients are available after the forest is cut or burned tend to wash away in the heavy rains. Tropical soils also do not retain nutrients well. 104) Every year certain parts of California have fires that sweep rapidly through the area, burning or endangering homes. What type of biome is found there, and why does it burn so frequently? Answer: This biome is chaparral. The plants there are adapted to the hot, dry summers by having waxy leaves that burn easily while leaving the plants' roots unharmed. 105) One of the most popular hikes in Rocky Mountain National Park is the tundra trail. What effects would you expect from hundreds of people walking on this trail every day during the season? Answer: Because the plants are so small, such as 50-year-old willows that are only a few inches tall, the damage done by a single careless hiker may last for many years. 106) What are the main factors that determine the locations of terrestrial biomes? Answer: The particular biome is determined by the availability of water and appropriate temperatures. 107) In one area is a desert ecosystem and in another area is a tundra. What two fundamental resources differ in the ecosystems of these two areas? Why are these two more important than the other fundamental resources? Answer: The ecosystems differ in temperature and moisture; these are the most important resources because they are less evenly distributed than are nutrients and energy. 108) Why do plants dominate and define communities on land? Answer: Because plants cannot escape from the weather, they tend to be precisely adapted to the climate in an area.

109) Why are most of the trees in temperate rain forests evergreens? Answer: There is abundant precipitation in winter months and the ground seldom freezes, so there is little need for the trees to lose their leaves. 110) Describe the climate in the northern coniferous forest, and explain how that climate favors the type of forest found there. Answer: Extremely cold winters with short summers favor small-needled conifers that evaporate little water but allow the trees to photosynthesize as soon as conditions are right. 111) Explain, in ecological terms, why cattle ranchers and conservationists have battled one another over cattle-grazing practices in the western shortgrass prairie biome of the American West. How has grazing changed the habitat? Answer: Overgrazing of grasses by cattle has altered the ecosystem to favor the growth of desert plants such as sagebrush, thus threatening the organisms native to the shortgrass prairie. The overgrazing allows the wind to erode the soils and contributes to water loss. 112) Plants from both the chaparral and the Arctic have waxy coatings even though the temperatures in the two biomes are vastly different. Why? Answer: In both biomes, water is available during only a brief season: the rainy season of the chaparral and the summer in the Arctic. The waxy coatings are an adaptation of the plants native to those regions to retain moisture during the dry times. 113) In many parts of the Amazon Basin, farmers have cut down the tropical rain-forest trees and planted crops. However, the farmers often abandon these croplands after a few years and move on. What are some possible reasons for this? Answer: Soils in the tropical rain forest are very poor in nutrients, in part because the nutrient capital of the forest is tied up in vegetation. Even if the trees are burned to release nutrients, the abundant rains quickly wash the "fertilizer" away. 114) As large tracts of rain forest disappear due to human activities, the region tends to become drier. Why? Answer: Trees can quickly take up the water that falls to the ground, and much of the rainfall in a rain forest comes from water transpired from the forest's leaves, thus producing an internal, regional cycle of water. 115) In what biome do plants tend to be evenly spaced with large, shallow root systems? Why? Answer: In deserts, water is very scarce, and intense competition among plants leads to a partitioning of resources that produces an even spacing pattern. Because desert storms can be brief and intense, large, shallow roots can soak up the water quickly. 116) Both the northern coniferous forest and the temperate rain forest are dominated by evergreen vegetation. What are the reasons in eachbiome? Answer: In the northern coniferous forest, the growing season is very short, and the few months of warm weather are too short to allow trees the luxury of regrowing leaves in the spring. The abundance of water in the temperate rain forest during winter months means that trees do not need to shed their leaves. 117) Describe the spatial patterns of light and nutrients in a lake, and explain why these patterns exist. Answer: Light decreases rapidly from the surface to the lower depths because water and suspended particles absorb light. Nutrients are tied up in organic matter, which sinks to the bottom and releases nutrients there through decomposition.

118) Scientists observing coral-reef communities have noted declines in coral reefs in regions that have both agricultural runoff and rising water temperatures. What are the possible reasons for these observations? Answer: Agricultural runoff may cause eutrophication, which reduces both light penetration and oxygen due to excess algal production. High water temperatures may encourage explosions of algal populations, which may release specific toxins. In addition, coral reefs expel the symbiotic algae when waters become too warm, thus cutting off the food source for the corals. 119) You are called to investigate a lake in your home town, where the residents fear that a broken pipe from the local sewage treatment plant has turned the formerly pristine lake eutrophic. What three things would you measure, or observe, in the lake to determine whether it is eutrophic? Answer: Possible options are decreased oxygen levels in deeper water, decreased water clarity, increased nitrogen levels, increased phosphate levels, increased levels of sewage bacteria, and increased algae growth. 120) Throughout history, some of the best farmland has been the flat areas along rivers. Why? Answer: These floodplain areas receive fresh additions of nutrient-rich sediments whenever the river floods. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

121) What biome would you expect to find at 60° N latitude and elevations of 3,500 meters? A) Ice and snow B) Tropical forest C) Coniferous forest D) Deciduous forest E) Tundra Answer: C

122) What biome would you expect to find at 45° N latitude and elevations of 2,500 meters? A) Coniferous forest B) Tundra C) Ice and snow D) Deciduous forest E) Tropical forest Answer: D 123) What biome would you expect to find at 30° N latitude and elevations of 1,500 meters? A) Tundra B) Tropical scrub forest C) Coniferous forest D) Ice and snow E) Deciduous forest Answer: B 124) The animals shown in the photographs are found in which biome?

A) Tropical rain forest B) Tundra C) Tallgrass prairie D) Savanna E) Northern coniferous forest Answer: D 125) As cities along the western coast of North America grew, people began building houses in the chaparral regions. Many homeowners have chosen to landscape with drought-resistant native plants in an effort of conserve water, a valuable resource in this dry biome. Nevertheless, the dry chaparral summer remains susceptible to fires. Nearly every year, fires sweep through the area, destroying homes, displacing people, and costing millions of dollars. What is the best solution to this problem? A) Plant species from damp areas to increase the moisture content in the area. B) Evacuate people during the fireseason. C) Plant tall-growing trees to increaseshade. D) Stop building homes in fire-proneareas. E) Immediately extinguish all fires in this area. Answer: D

126) In an attempt to stop desertification, some groups have changed the way they work with the land. They plant trees to stop erosion, build small barriers to slow water runoff on slopes, and bring food to their animals rather than letting them graze freely. Why would these techniques help stop desertification? A) Trees, runoff diversion, and changes in grazing patterns all conserve water. B) People move out of the areas rather than follow these techniques, lessening the water demand. C) The trees increase evaporation. D) They break up the cyanobacteria in the soil. E) They increase the amount of water used in the area. Answer: A

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) The major goal of conservation biology is to A) preserve the diversity of living organisms. B) increase the population sizes of all species. C) restore the biosphere to its previously unspoiled condition. D) repair the damage to ecosystems done by introduced species. E) make the biosphere more habitable for humanity. Answer: A 2) The variety and abundance of the different species that make up a community is the A) species diversity B) conservation biology C) genetic diversity D) ecosystem services E) ecosystem diversity

of a community.

Answer: A 3)

takes into account both the biotic (living) communities and the abiotic (nonliving) environments on which the communities depend. A) Ecosystem diversity B) Ecosystem services C) Conservation biology D) Genetic diversity E) Species diversity Answer: A

4) Maintaining soil fertility, purifying water, producing oxygen, and decomposing waste are all examples of A) biodiversity. B) biocapacity. C) species diversity D) ecosystem services. E) ecological footprint. Answer: D 5) In 2005, the authors of the Millennium Ecosystem Assessment concluded that services is being degraded. A) 5 B) 20 C) 95 D) 0 E) 60 Answer: E 6) Plants help reduce flooding by A) removing soil. B) decreasing the amount of water returned to the air. C) breaking down the soil. D) increasing CO2 levels. E) increasing the soil's ability to hold water. Answer: E

% of Earth's ecosystem

7) Tropical rain forests provide all of the following EXCEPT A) ecotourism. B) traditional medicines. C) wood used for cooking by local residents. D) hardwoods for consumers worldwide. E) large supplies of gasoline. Answer: E 8) Which of the following is NOT an example of how plant communities continue to support healthy ecosystems? A) Plants increase levels of CO2, by releasing CO2 as a by-product of photosynthesis. B) Plants prevent flooding by absorbing water through their extensive root systems. C) Forests support the water cycle, through evaporation returning water to the atmosphere. D) Leafy trees provide shade, thereby reducing temperatures. E) Plant roots stabilize soil and prevent erosion. Answer: A 9) Traditional medicines, which are used by the majority of people in less developed countries, are primarily derived from A) commercially purchased ingredients. B) rock. C) animals. D) water. E) plants. Answer: E 10) In the soil, A) plants B) fungi C) worms D) bacteria E) insects

convert atmospheric nitrogen into a form that plants can use.

Answer: D 11) Plants prevent erosion by A) recycling nutrients. B) holding water. C) blocking winds and stabilizing soil with extensive root systems. D) supporting animals that consume excess water. E) promoting flooding. Answer: C 12) Coastal wetlands, or marshes, serveto A) "absorb" water from major storms. B) provide a habitat for majorpredators. C) return nitrogen to the atmosphere. D) purify water farther upriver. E) store phosphorus. Answer: A

13) What human activity can cause flooding along riverbanks? A) Removal of forests and wetlands along the river B) Decreased conversion of forests tofarmland C) Decreased soil formation D) Overfishing E) Increased evaporation due to fewertrees Answer: A 14) Forests influence local climates by A) releasing water into the atmosphere. B) increasing the temperature via photosynthesis. C) increasing the amount of waterrunoff. D) releasing carbon dioxide. E) increasing evaporation by blocking winds. Answer: A 15) Cutting down rain forests may result in the local climate becoming A) hotter and drier. B) hotter and wetter. C) cooler and drier. D) cooler and wetter. E) It is not expected to affect the local climate. Answer: A 16) Deforestation affects the climate in what way? A) Decreasing the habitat space for forest-dwelling animals B) Increasing the levels of carbondioxide C) Decreasing the amount of wood available for building shelter D) Decreasing global temperature E) Increasing the levels of oxygen Answer: B 17) Why is it important to preserve the genes of the wild relatives of crop plants? A) Beneficial genes from the wild relatives may be transferred into crop plants. B) It is not important because the wild species have all become extinct. C) It is not important because the human population no longer eats wild foods. D) The wild relatives are the food sources for all domestic animal species. E) By preserving the genes, we can control the growth of the wild relatives, which threaten our crop plants. Answer: A 18) Most of the world's food supply comes from A) only 12 plant crops. B) frost-resistant crops. C) more than 100 rain-forest species. D) salt-tolerant crops. E) wild plants. Answer: A

19) Attempts are being made to restore the Kissimmee River, located in Florida's Heartland. What ecological benefit could be derived from this restoration? A) Improving the water quality and restoring biodiversity B) Using more land for agriculture C) Reducing ecotourism D) Decreasing biodiversity E) Expanding development Answer: A 20) In 1947, prolonged flooding of the Kissimmee River, located in Florida's Heartland, inundated the Kissimmee basin as well as the surrounding cities, prompting citizens to cry out for flood control. The river was transformed into a canal, and associated wetlands with their populations of wetland-dependent flora and fauna declined drastically. The loss of wetlands could have resulted in A) an increase in native plant populations with an accompanying decline in herbivore species. B) a pollution problem. C) enhanced natural water purification. D) a decline in populations of invasive species. E) a decrease in erosion of the river basin. Answer: B 21) The most likely explanation for any mass-extinction event is A) loss of genetic diversity due to inbreeding. B) rapid environmental change. C) human activity. D) a gradual increase in global temperature. E) coevolution of predator and prey species. Answer: B 22) Some biologists believe that life on Earth is in the midst of a sixth major mass-extinction event caused by A) loss of genetic diversity due to inbreeding. B) a gradual decrease in global temperature. C) coevolution of predator and prey species. D) human activity. E) sustainable agricultureefforts. Answer: D 23) It is difficult to estimate current rates of extinction, but we know that extinction rates have risen dramatically in recent years because A) new species are evolving as fast as species are becoming extinct. B) the fossil record is unreliable. C) background extinction rates have increased. D) most species in danger of extinction are microscopic. E) current rates of extinction are much higher than that of background rates. Answer: E

24) The idea that several species in a community have functionally equivalent roles but vary in their ability to withstand environmental stressors is called the hypothesis. A) biocapacity B) multiple species C) unextinction D) redundancy E) rivet Answer: D 25) A species is fundamentally essential to an ecosystem; its loss changes the structure of the entire community, even though it may only represent a small portion of the population. A) redundant B) keystone C) baseline D) footprint E) rivet Answer: B 26) The ecological footprint of the human species is about A) 50% of Earth's biocapacity. B) 80% greater than Earth's biocapacity. C) equal to Earth's biocapacity. D) 80% of Earth's biocapacity. E) 50% greater than Earth's biocapacity. Answer: E 27) Comparison of the human ecological footprint to Earth's biocapacity suggests that A) the human population can continue at its present level of resource usage indefinitely. B) the human population is growingslowly. C) the human population cannot sustain its current level of resource usage. D) global warming is seriously damaging most ecosystems. E) the human population will soon rapidly decrease in size. Answer: C 28) The leading cause of extinction by human activities worldwide is A) predation. B) invasive species. C) overexploitation. D) pollution. E) habitat fragmentation. Answer: E 29) Which human activity is NOT a threat to biodiversity? A) Importing pigs and goats in Hawaii for food B) Cattle ranching C) No-till farming D) Building a large sugarcane plantation in a tropical rain forest E) Application of synthetic fertilizers Answer: C

30) Much of the tropical rain-forest land that has been lost has been used for A) airfields to support ecotourism. B) human dwellings. C) recreational areas. D) wildlife preserves. E) farmland. Answer: E 31) The largest threat to global biodiversity, as identified by the International Union for Conservation of Nature (IUCN), is A) habitat destruction. B) phosphate pollution. C) global warming. D) lack of farmland. E) introduced species. Answer: A 32) Even when a natural ecosystem is not completely destroyed, it may become broken into small pieces. This is known as A) pollution. B) habitat fragmentation. C) clear-cutting. D) habitat destruction. E) no-till cropping. Answer: B 33) Large mammals and birds require A) 2 B) hundreds of C) millions of D) 4 E) dozens of

acres of continuous suitable habitat for food and territory.

Answer: B 34) The minimum viable population is the A) smallest number of males needed to maintain a population. B) smallest number of organisms capable of maintaining a population. C) number of organisms produced by an inbred population. D) number of organisms that can be spread over a fragmented habitat. E) number of organisms that can reproduce in a population. Answer: B 35) Overexploitation of many species has increased due to the growing demand for wild animals and plants, and A) global warming. B) sustainable agriculture, which has become more popular. C) an increase in the number of core reserves. D) the dramatic increase in world population. E) technological advances that have made it easier to obtain the animals and plants. Answer: E

36) Sea turtle populations are threatened with extinction by natural dangers, and humans increase that threat because sea turtles A) are spreading into coral reefs. B) are caught in nets along with other species being fished. C) are overexploited for research and development. D) are overexploited as pets. E) are difficult prey for human poachers to capture. Answer: B 37) In less-developed countries, many species are being harvested unsustainably because A) they are considered a danger to humans. B) pollution has reduced their population sizes dramatically. C) people thoughtlessly destroy what they do not need. D) they are hunted and killed because they carry human diseases. E) the people must eat or sell the species' products to survive. Answer: E 38) An introduced species is "invasive" if it A) survives in its new habitat and forms mutually beneficial relationships with native species. B) outcompetes native species in its new habitat. C) cannot successfully maintain a population in the new habitat. D) does not cause significant harm to native species. E) is a threat to humans. Answer: B 39) Pollutants such as A) nitrogen B) sulfur C) carbon monoxide D) water E) bisphenol A

may affect the reproductionof organisms.

Answer: E 40) As a result of globalwarming, A) species' ranges are shifting toward the equator. B) species are becoming active later in the spring. C) there are greater extremes in weatherpatterns. D) the ozone layer is becoming thicker. E) forests are expanding in range. Answer: C 41)

occurs when human developments break up natural ecosystems into smaller areas. A) Habitat fragmentation B) Overexploitation C) Conservation biology D) Sustainable development E) Species invasion Answer: A

42) Adult sea turtles are primarily threatened by A) beach development, hunting, and polluted ocean waters. B) beach development. C) beach development and hunting. D) hunting. E) polluted ocean waters. Answer: C 43) The greatest natural threat to newly hatched sea turtles is A) ecotourism. B) polluted ocean waters. C) beach development. D) predation by native species. E) drowning. Answer: D 44) The conservation organization TAMAR has had some success in protecting sea turtles by A) fundraising in wealthy countries. B) making beautiful jewelry from turtleshells. C) increasing the market for turtleeggs. D) lobbying for legislation that supports the cause. E) engaging the local community in conservation efforts. Answer: E 45) Habitat fragmentation has forced many species into smaller habitats, which results in increased mortality within populations. To give these species access to larger habitats, wildlife biologists developed A) minimum critical areas. B) underground tunnels for animal movement. C) enormous water tanks. D) wildlife corridors. E) diverse communities of plants. Answer: D 46) The goals of conservation biologists include all of the following EXCEPT A) studying the natural impacts of human activities. B) cataloguing the number of species. C) maintaining and restoring natural ecosystems. D) reversing the loss of biodiversity. E) working toward resource sustainability. Answer: B 47) One goal of conservation biology is to prevent extinction caused by A) predation. B) human activity. C) asteroid impacts. D) disease. E) interaction of native species. Answer: B

48) Core reserves are areas where A) wildlife species benefit from extensive conservation programs, including nurseries and clinics. B) only human activities that have low impact on the native wildlife are allowed. C) humans have irrevocably destroyed the local ecosystem. D) humans are allowed to use and develop the areas as they see fit. E) humans are forbidden from entering. Answer: B 49) Which of the following does NOT represent a sustainable approach to development? A) Installing energy-efficient features, such as good insulation and tight weather stripping, in your house B) Continuing human population growth at current levels C) Identifying recycling options in your community and recycling only those things that are accepted D) Choosing the most fuel-efficient form of vehicle that meets your needs E) Using energy-efficient compact fluorescent or LED bulbs Answer: B 50) Unsustainable farming practices include A) abandoning the use of irrigation to water fields. B) abandoning fields and allowing them to go through natural succession. C) planting different crops in the same field in alternating years. D) mulching fields after harvest. E) using herbicides and pesticides. Answer: E 51) Organic farming involves A) planting genetically engineered crops only. B) using organic pesticides and herbicides. C) allowing natural predators to control pests. D) adding organic fertilizers to the soil. E) using large farm equipment to fertilize, plow, and harvest. Answer: C 52) Food that is produced using unsustainable farming practices tends to A) be less susceptible to pestdamage. B) have a lower fat content. C) have a longer shelflife. D) have more complex carbohydrates. E) be cheaper. Answer: E 53) The detritivores and decomposers in soil are responsible for recycling nutrients. A) True B) False Answer: A 54) In the wild, plants depend on bacteria in the soil to provide nitrogen. A) True B) False Answer: A

55) Trees alter runoff patterns, causing increased erosion and potential flooding. A) True B) False Answer: B 56) In heavily forested areas, the trees reduce evaporation and disrupt the normal water cycle. A) True B) False Answer: B 57) Wetlands purify water by removing sediments and pollutants. A) True B) False Answer: A 58) Plant roots increase the soil's capacity to hold water, so vegetation contributes to erosion and flood control. A) True B) False Answer: A 59) Under the redundancy hypothesis, if one species is removed from an ecosystem, then another organism in that ecosystem that occupies a similar niche will take its place, leading to minimal disruption. A) True B) False Answer: A 60) Removal of a keystone species from an ecosystem has minimal effect because other species compensate and take over its role. A) True B) False Answer: B 61) The mass extinction currently taking place is most likely due to human activities. A) True B) False Answer: A 62) Rich consumers support sustainability and biodiversity by paying high prices for rare products, such as elephant-tusk ivory, rare orchids, and exotic birds. A) True B) False Answer: B 63) Habitat fragmentation increases the breeding success of a species. A) True B) False Answer: B

64) Invasive species cannot be introduced to the Great Lakes because they are isolated from the oceans. A) True B) False Answer: B 65) Global warming is accelerating the growth of coral reefs. A) True B) False Answer: B 66) The most serious threat to biodiversity is habitat destruction. A) True B) False Answer: A 67) Global climate change will cause deserts to become hotter and wetter. A) True B) False Answer: B 68) In aquatic environments, high levels of nutrients can act as pollutants. A) True B) False Answer: A 69) Aquatic species found in lakes are not particularly vulnerable to invasive species. A) True B) False Answer: B 70) Wildlife corridors are designed to keep predators and their prey isolated from one another. A) True B) False Answer: B 71) In the ocean, whales are the keystone species. A) True B) False Answer: A 72) Once commercial whaling stopped, whale populations quickly returned to their pre-whaling sizes. A) True B) False Answer: B 73) Sustainable agriculture depends on planting large tracts of high-profit crops. A) True B) False Answer: B

74) Farmers who practice no-till methods commonly use herbicides. A) True B) False Answer: A 75) Buying food that is commercially produced supports sustainable agriculture. A) True B) False Answer: B 76) Human population growth poses a threat to sustainable development. A) True B) False Answer: A SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 77) The term

describes the variety of living organisms that inhabit Earth.

Answer: biodiversity 78) The term indirectly.

refers to the ways in which ecosystems provide benefits to people, either directly or

Answer: ecosystem services 79) A rapidly growing recreation industry where people travel to visit unique biological communities is called . Answer: ecotourism 80) The discipline of measures the trade-offs between the monetary value of human developments and the loss of ecosystem services. Answer: ecological economics 81) When many species disappear from the fossil record in a short amount of time, this is called a

Answer: massextinction 82) A species that is in danger of extinction is described by the IUCN as

Answer: threatened 83) An estimation of the area of the Earth's surface a human requires to produce the resources he or she needs and to remove the wastes he or she produces is called a(n) . Answer: ecological footprint 84) The of the planet is the area of Earth's surface that is actually available to generate resources and process wastes. Answer: biocapacity 85)

happens when people hunt, fish, or harvest a species at a rate that exceeds its natural capacity to sustain itself. Answer: Overexploitation

86) The

is a keystone predator in the ocean.

Answer: whale 87) Natural areas that are protected from human development are called

Answer: corereserves 88)

are strips of protected land that allow animals to travel between core reserves. Answer: Wildlifecorridors

89) A(n) community.

is an animal whose predation on other species has major effects on the structure of the biological

Answer: keystone predator 90) The principle of nature's limits.

requires that the human species adopt lifestyles and development paths that respect

Answer: sustainable development 91) In the technique of cropping, farmers do not plow, but they leave leftover cover crops in the fields after harvest to create mulch for the next year's crops. Answer: no-till 92) What are some benefits of sustainable development? Answer: Sustainable development promotes long-term ecological and human well-being because people live within the carrying capacity of supporting ecosystems, minimize the use of nonrenewable resources, and use renewable resources in a manner that allows them to be available far into the future. 93) What is no-till farming? Answer: No-till farming is a technique of cropping in which farmers do not plow, but they leave leftover cover crops in the fields after harvest to create mulch for the next year's crops. 94) Why is genetic diversity within species important? Answer: Genetic diversity allows a species to live in a variety of environments and adapt to changes in the environment. 95) What ecosystem services do wetlandsperform? Answer: Wetlands neutralize pollutants, control flooding, and provide breeding grounds for birds, fish, and other animals. 96) Applying ecological economics, how would you decide whether to develop a wetland for vacation property or to preserve it? Answer: You would weigh the costs and benefits of the development, taking into account the potential cost in property damage during future storms that may be minimized by the presence of the wetland, the purifying effects of the wetland, and the loss of habitat for local species. 97) What causes mass extinctions? Answer: Several reasons have been proposed, including human impact, meteorites, and sudden climate change.

98) What two factors are most responsible for the decline in worldwide biodiversity? Answer: (1) The amount of resources used to support human lifestyles is increasing, and (2) human activities are causing direct damage to habitats. 99) What is the difficulty with establishing small, isolated reserve areas for the preservation of threatened species? Answer: The species may require large areas of continuous habitat and may be injured or killed when trying to cross nonreserve areas. 100) How can sustainable fishing beaccomplished? Answer: There must be limits placed on catches, technological development to minimize damage to other species, and preservation of the spawning grounds of fished species. 101) Why is the term sustainable development nearly an oxymoron? Answer: Development often means the destruction of natural ecosystems and their replacement with human settlements, which by definition does not sustain ecosystems. 102) What is the single most important factor that makes worldwide sustainable development difficult? Answer: The size of the human population is probably at a level that makes sustainability difficult, and the population continues to grow. 103) How can you, as an individual consumer, conserve energy? Answer: Many answers are possible, including ways to lower heating, cooling, and transportation costs and the use of fuels, hot water, and appliances. 104) How can you, as an individual consumer, conserve materials? Answer: Many answers are possible, including ways to recycle waste materials, reuse "trash," restrict water usage, and purchase products that contain recycled material.

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

105) According to the graph, the human population's biological footprint in 1965 was estimated at A) 0.5 Earth. B) 1 Earth. C) 0.6 Earth. D) 1.2 Earths. E) 0.8 Earth. Answer: C 106) According to the graph, the human population's biological footprint in 2000 was estimated at A) 0.8 Earth. B) 0.5 Earth. C) 0.6 Earth. D) 1.2 Earths. E) 1 Earth. Answer: D

107) Which types of species are most likely to disappear from fragmented forests?

A) Only animals will disappear; plants do not need much space. B) Microbes that reproduce asexually will disappear. C) Species that reproduce in small patches will disappear. D) Species that require large tracts of land to find food and mates will disappear. Answer: D 108) In an attempt to control aphids that are destroying his plums, a farmer in Iowa imports a colony of Asian ladybugs that feast on the aphids. The Asian ladybugs are not eaten by the local bird populations. The Asian ladybug population multiplies quickly, displaces the local ladybugs, eliminates the aphids, and begins to eat other local insects. The Asianladybug A) qualifies as an invasive species. B) is increasing the biodiversity of the orchard. C) is a threatened species. D) is being overexploited. E) is responsible for habitat fragmentation in the plum orchard. Answer: A 109) Native Americans planted crops of corn, squash, and beans. The beans increased the level of nitrogen in the soil. The corn required high levels of nitrogen and provided a support for the beans to climb and receive more sunlight. The large leaves on the squash shaded the ground and limited weed growth. This agricultural method A) increased the number of pests in the fields. B) caused mass extinctions. C) created wildlife corridors. D) reduced the ecosystem services. E) is a type of sustainable agriculture. Answer: E

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Most body systems maintain homeostasis through A) redundant B) alternating C) monitoring D) negative feedback E) positive feedback

systems.

Answer: D 2) Hypertension damages the lining of the arterioles of the kidneys, which results in the release of molecules that further raise blood pressure. This is an example of a(n) A) positive feedback loop. B) electrochemical mechanism. C) controllingmechanism. D) negative feedback loop. E) uncontrolled mechanism. Answer: A 3) What is the primary reason internal homeostasis must be maintained? A) Enzymes must retain their correct three-dimensional structure. B) Wide swings in the internal environment interfere with normal metabolic reactions. C) Homeostasis prevents the wasting of stockpiles of coenzymes. D) Unregulated variations cause the cells' DNA to mutate. E) Most organisms have not evolved mechanisms to control positive feedback systems. Answer: B 4) In the description of homeostasis, the term dynamic constancy refers to A) the use of ATP to initiate a cascadeeffect. B) a constant movement toward equilibrium. C) the fact that even though physical and chemical changes do occur, conditions are kept within a range. D) the direct interaction of each positive feedback system with its corresponding negative feedback system. E) a disregarded theory that suggested there were no external energy requirements to maintain cell homeostasis. Answer: C 5) Which of the following is an example of a positive feedback loop? A) A person altering her breathing rate to keep blood pH between 7.35 and 7.45 B) Stress altering the normal menstrual cycle, which delays menstruation, thereby causing more stress C) The kidney retaining water when the organism becomes dehydrated D) A hummingbird maintaining a constant internal body temperature Answer: B 6) After eating a large meal of pasta, an individual's blood sugar levels are elevated. In response to this, the pancreas secretes a hormone called insulin, which acts to lower blood sugar levels. Once the blood sugar levels drop to the normal level, the pancreas stops secreting insulin. This is an example of A) reactions between carbon monoxide andacids. B) a negative feedback loop. C) a positive feedback loop. D) energy being made into proteins. E) acid-base imbalance. Answer: B

7) Which of the following controls the temperature in endothermic animals? A) Autonomic nervous system B) Cerebral cortex C) Positive feedback systems D) Hypothalamus E) Reflexive skeletal muscles Answer: D 8) One biological example of a positive feedback system is A) temperature regulation. B) mammalian birth. C) water balance. D) blood pHlevels. Answer: B 9) What happens if homeostasis is NOT maintained? A) Cells begin dividing uncontrollably. B) Organisms stop using negative feedbackloops. C) Cellular metabolism is unchanged. D) Cells lose the ability to carry out normal functions. E) Organisms functionbetter. Answer: D 10) In humans, the body needs to maintain oxygen levels within narrow homeostatic ranges. If the blood oxygen level drops below that range, the body responds by A) using negative feedback loops to further lower the oxygen level. B) setting this lower oxygen level as the new normal. C) using positive feedback to raise the oxygen level. D) using negative feedback loops to return the oxygen level to normal. E) using positive feedback to further lower the oxygen level. Answer: D 11) Groups of tissues that function together form a(n) A) gland. B) individual. C) organ. D) system. E) organ system. Answer: C 12) Similar cells that perform a particular function are known as A) organs. B) organ systems. C) tissues. D) organisms. Answer: C

13) What is a gland? A) A type of tissue that makes cartilage B) The functional unit of the skeletal system C) A cluster of epithelial or nervous cells that release a secretion D) A special connection between muscle cells E) A group of cells that replaces the stomach lining every few days Answer: C 14) The lining of the trachea is formed from A) nerve B) epithelial C) muscle D) connective E) undifferentiated

tissue.

Answer: B 15) Which tissue is characterized by a basement membrane and a single layer of flattened cells with a free surface? A) Stratified epithelium B) Simple epithelium C) Undifferentiated tissue D) Connective tissue E) Muscle tissue Answer: B 16) Blood isa type of A) nerve B) connective C) muscle D) endothelial E) epithelial

tissue.

Answer: B 17) The lining of the respiratory system is composed of A) connective B) nerve C) adipose D) muscle E) epithelial

tissue.

Answer: E 18) In stratified epithelium, such as the epidermis of the skin, cell division occurs A) throughout all the layers. B) in the surface cell layeronly. C) in the cells at the base layer only. D) in the basement membraneonly. Answer: C

19) The basement membrane in epithelial tissue A) provides strength and support. B) contracts to move theskin. C) is the layer that contains the dividing cells. D) waterproofs the epithelium. E) transmits nervous stimuli. Answer: A 20) The mucus that traps dust particles in the lungs is produced by A) endocrine glands. B) connective tissue. C) muscle tissue. D) epithelial tissue. E) adipose tissue. Answer: D 21) The pads that cushion the vertebrae are made of A) cartilage. B) smooth muscle tissue. C) fat. D) matrix. E) bone. Answer: A 22) Large amounts of extracellular material are characteristic of A) loose connective tissue. B) nervous tissue. C) simple epithelium. D) smooth muscle. E) stratified epithelium. Answer: A 23) Widely scattered cells embedded in large amounts of extracellular material composed of randomly arranged collagen fibers make up A) adipose tissue. B) stratified epithelial tissue. C) dense connective tissue. D) cardiac muscle. E) loose connective tissue. Answer: E 24) Cartilage, bone, and blood are examples of A) connective B) epithelial C) muscle D) nerve E) undifferentiated

tissue.

Answer: A

25) Which of the following tissues is used for energy storage? A) Blood B) Adipose C) Epithelial D) Cartilage E) Dense connective Answer: B 26) Which tissue helps endotherms maintain body temperature in cool weather? A) Adipose B) Simple epithelium C) Cartilage D) Bone E) Dense connective Answer: A 27) How are cardiac and smooth muscles similar? A) Both are typically under conscious control. B) Both are involuntary. C) Both have only thin proteinfilaments. D) Both are connected to bones. E) Both use cyclic adenosine monophosphate (cAMP) as an energy source. Answer: B 28) Which type of muscle is under voluntary control? A) Oxygen enriched B) Smooth C) Epithelial D) Skeletal E) Cardiac Answer: D 29) Which tissue contains large amounts of densely packed collagen fibers that run parallel to each other? A) Tendons B) Blood C) Lymph D) Nerve E) Adipose Answer: A 30) Which tissue is in direct contact with the external environment of an animal? A) Epithelial B) Endothelial C) Muscle D) Nerve E) Connective Answer: A

31) Connective tissues include lymph, ligaments, tendons, and A) vessel linings. B) exocrine glands. C) cartilage. D) cardiac muscle. E) skin cells. Answer: C 32) When you move your fingers to turn the page, you are using the nervous system and A) endocrine glands. B) simple epithelium. C) skeletal muscle. D) cardiac muscle. E) adipose tissue. Answer: C 33) Which cells are designed to conduct electrical impulses? A) Skeletal muscle cells B) Adipose cells C) Nerve tissue D) Connective tissue E) Glial cells Answer: C 34) The retina of the eye responds to light, converting it into electrical impulses. The retina is made up of A) neurons. B) bone. C) simple epithelium. D) smooth muscle. E) cartilage. Answer: A 35) Hair follicles are a variation of A) dense connective B) loose connective C) epithelial D) nerve E) muscle

tissue.

Answer: C 36) The skin is an example of a(n) A) organ system. B) organ. C) cell. D) undifferentiated mass. E) tissue. Answer: B

37) Together, the stomach, intestines, mouth, and esophagus form a(n) A) ectotherm. B) organ system. C) tissue. D) cell. E) organ. Answer: B 38) The system is composed of the kidneys, ureters, bladder, and urethra. A) respiratory B) reproductive C) digestive D) urinary E) circulatory Answer: D 39) In addition to the nervous system, which vertebrate organ system controls physiological processes in animals? A) Respiratory B) Reproductive C) Muscular D) Skeletal E) Endocrine Answer: E 40) Which tissue type is most suited to areas of the body in which the cells need continuous replacement to repair damage from daily wear andtear? A) Epithelial B) Connective C) Muscle D) Nerve Answer: A 41) The maintenance of internal conditions within narrow ranges is known as homeostasis. A) True B) False Answer: A 42) Because of the freezing temperatures of the deep ocean, all deep-sea fish must be endotherms. A) True B) False Answer: B 43) Most of the homeostatic functions in the body are regulated by positive feedback loops. A) True B) False Answer: B 44) Maintaining homeostasis requires the coordinated efforts of multiple negative feedback loops. A) True B) False Answer: A 7

45) When an animal's body temperature drops below normal, the body responds to raise the temperature using positive feedback loops. A) True B) False Answer: B 46) The integumentary system plays a role in temperature regulation. A) True B) False Answer: A 47) Cardiac muscle requires input from the nervous system to contract. A) True B) False Answer: B 48) Hormones are secreted by exocrine glands directly into a body cavity or onto a body surface, rather than being transported by the blood. A) True B) False Answer: B 49) The extracellular matrix in dense connective tissue contains large amounts of calcium, which causes the tissue to harden and become solid. A) True B) False Answer: B 50) The basement membrane of epithelial tissues produces a waterproof barrier of cells to protect the tissue above it. A) True B) False Answer: B 51) Connective tissues are made up of cells surrounded by an extracellular matrix, the consistency of which can vary from a liquid to a solid. A) True B) False Answer: A 52) Glial cells provide structural and chemical support to neurons. A) True B) False Answer: A 53) The dermis of the skin is composed of stratified epithelium. A) True B) False Answer: B

54) The outer layer of the skin is the dermis. A) True B) False Answer: B 55) The blood vessels that provide nourishment for the skin cells are located in the dermis only. A) True B) False Answer: A SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 56) The ability to maintain an internal environment within specific ranges is referred to as

Answer: homeostasis 57) Organisms that can maintain a fairly consistent internal body temperature through metabolic reactions are known as . Answer: endotherms 58) Regardless of the temperature of the environment they find themselves in, endotherms maintain a nearly consistent . Answer: body temperature 59) The body temperature of an

changes to match the temperature of the external environment.

Answer: ectotherm 60) An endotherm uses

feedback loops to maintain homeostasis.

Answer: negative 61) When the body's response to swelling caused by an insect bite is to release histamine, which causes more swelling and releases more histamine, the organism is using a feedback loop. Answer: positive 62) While sitting in a hot car, your body begins to sweat, which cools the body back down. This illustrates a feedbackloop. Answer: negative 63) A(n)

is made up of two or more tissue types that work together to carry out body functions.

Answer: organ 64) Epithelial tissues are attached to the underlying tissue by a noncellular protein layer called the membrane. Answer: basement 65) Glands that lack ducts and use the bloodstream to transport their products are called Answer: endocrine 66) Bones are connected to other bones by

Answer: ligaments

glands.

67) Blood is a type of connective tissue that contains fibers and cells suspended in a

matrix.

Answer: fluid (or liquid) 68) The matrix in cartilage is made of protein fibers called

Answer: collagen 69) A calcium phosphate matrix is characteristic of

, a specialized connective tissue.

Answer: bone 70) Cells that store lipids (fats) for long-term energy are found in

tissue.

Answer: adipose 71)

glands are a form of epithelial tissue that secretes substances through a duct. Answer: Exocrine

72)

epithelium is several cell layers thick and is specialized to withstand wear and tear. Answer: Stratified

73) Tightly packed collagen fibers arranged in either parallel rows or an irregular meshwork are characteristic of connective tissue. Answer: dense 74) The digestive and respiratorytracts contain

muscle.

Answer: smooth 75) Cells that generate electrical impulses form

tissue.

Answer: nerve (or nervous) 76) Compare the mechanisms that endotherms and ectotherms use to regulate body temperature. Answer: Endotherms produce heat through metabolic reactions, whereas ectotherms derive heat from the environment. 77) Why are negative feedback loops more effective at maintaining homeostasis than positive feedback loops? Answer: Negative loops counteract a stimulus to return the body to homeostatic levels. For example, when an animal's body temperature increases, blood vessels dilate and sweat is produced to help lower the temperature back to normal. Positive loops respond to a stimulus by moving the body further from the homeostatic normal. 78) Why do organisms need to maintain homeostasis? Answer: Metabolic reactions work at optimal levels within limited ranges of temperature, pH, and other factors. When the body is outside those ranges, metabolism functions at less-than-optimal levels, which may cause illness or even death. 79) What are the four major types of tissues? Answer: The four major types are epithelial tissue, connective tissue, nerve tissue, and muscle tissue. 80) How do exocrine glands differ from endocrine glands? Answer: Exocrine glands secrete substances through ducts. Endocrine glands lack ducts and secrete substances (hormones) directly into the extracellular fluid.

81) What characteristics of stratified epithelium make it suitable as an external covering? Answer: Stratified epithelium has the ability to continuously produce new cells to repair damaged cells. The new cells are produced at the base layer and move toward the surface. By the time the cells reach the surface, they are dead and form the water-resistant layer that provides additional protection. 82) What characteristic defines muscle tissue? Answer: All muscle tissue has the ability to contract and then relax to return to its original condition. 83) Why do neurons need glialcells? Answer: Glial cells provide insulation for neurons, help regulate metabolism, provide structural support, and help maintain the normal metabolic functioning of neurons. 84) For an organism to maintain proper neurological function, sodium and potassium levels must be maintained within narrow ranges. How would the body respond if a person took in excessive amounts of potassium? Answer: The body would use negative feedback mechanisms to return to homeostasis. This involves the endocrine, digestive, circulatory, and urinary systems. 85) Which tissues are found in a sample of skin? Answer: Skin is a complex organ that contains epithelium, smooth muscle, nerve tissue, and several types of connective tissues. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 86) This feedback loop is an example of

feedback.

A) negative B) positive Answer: A

87) The tissue shown in the figure is A) stratified epithelium. B) skeletal muscle. C) loose connective tissue. D) adipose tissue. E) nerve tissue. Answer: A 88) The tissue shown in the figure forms A) bone. B) fat. C) blood. D) the digestive system. E) skin. Answer: E

89) The tissue shown in the photograph forms

A) smooth muscle. B) bone. C) nerves. D) skeletal muscle. E) dense connective tissue. Answer: E 90) The tissue in the photograph is an example of

tissue.

A) epithelial B) muscle C) nerve D) connective Answer: D

91) This tissue is

A) cardiac muscle. B) nerve tissue. C) smooth muscle. D) adipose tissue. E) simple epithelium. Answer: A 92) The tissue in the photographis

A) nerve tissue. B) connective tissue. C) skeletal muscle. D) simple epithelium. E) stratified epithelium. Answer: C

93) The common garter snake (Thamnophis sirtalis) is found throughout North America. In the South, it is active year round. In the North, it is active during the warmer months but hibernates during the winter. It is commonly found basking on warm rocks during cool mornings. This lifestyle indicates that the snake is probably A) ectothermic. B) thermoneutral. C) photosynthetic. D) endothermic. Answer: A 94) While working in a forensic lab, you are given a bit of tissue to analyze. It has several layers. The upper surface consists of dead, flattened cells. As you move deeper into the tissue, the cells look healthier. The bottom layer of cells is actively dividing. Under the dividing layer is an acellular protein goo. You identify the sample as tissue. A) cardiac muscle B) loose connective C) dense connective D) stratified epithelial E) adipose Answer: D 95) You are given a sample of tissue to identify. The cells contain large amounts of protein arranged in stripes. When an electrical charge is applied to it, the tissue twitches and then relaxes. You classify this sample as tissue. A) stratified epithelial B) adipose C) loose connective D) skeletal muscle E) simple epithelial Answer: D

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Of the following answer choices, which would NOT be found in a closed circulatory system? A) Hemocoel B) Heart C) Vessels D) Blood Answer: A 2) Which of these animals has a closed circulatory system? A) Earthworm B) Clam C) Spider D) Snail E) Insect Answer: A 3) What is the advantage of a closed circulatory system over an open one? A) A closed system carries moreblood. B) Blood flows more slowly in a closed system. C) There are more blood cells in a closed system. D) A closed system moves blood more efficiently. E) In a closed system, the blood comes nearer to each cell. Answer: D 4) In a grasshopper, all the body tissues are bathed in blood that is in the A) tracheae. B) heart. C) spiracles. D) capillaries. E) hemocoel. Answer: E 5) In animals that have open circulatory systems, the interstitial fluid that functions as blood is called A) plasma. B) hemolymph. C) leukocyte. D) lymph. E) hemocoel. Answer: B 6) In vertebrates, which heart chamber supplies oxygenated blood to the body cells? A) Right ventricle B) Right atrium C) Left atrium D) Left ventricle Answer: D

A three-chambered heart A) has three ventricles. B) has three atria. C) has two atria and oneventricle. D) has one atrium and twoventricles. E) is found in fish. Answer: C 8) The aorta A) connects the right and left ventricles of the heart. B) contains blood with low pressure. C) is a major vein. D) is a major artery. Answer: D 9) In which vertebrate group are there two atria but only a single ventricle? A) Birds B) Fishes C) Some reptiles D) Crocodiles E) Mammals Answer: C 10) Which of the following have four-chambered hearts? A) Spiders B) Birds C) Frogs D) Fishes Answer: B 11) Which set of chambers supplies blood to the pulmonary circulation? A) Right atrium and right ventricle B) Atria C) Left atrium and left ventricle D) Ventricles Answer: A 12) Which heart chamber is the most muscular? A) Left atrium B) Right ventricle C) Left ventricle D) Right atrium Answer: C 13) The left ventricle is more muscular than the right ventricle because it must push the blood A) through the pulmonary arteries only. B) against gas pressure in thelungs. C) through wider blood vessels. D) through the body's extensive system of vessels that nourish all cells. Answer: D

14) Gap junctions A) connect veins and arteries. B) prevent the backflow of blood from the ventricles to the atrium. C) are found in white bloodcells. D) allow the rapid passage of electrical signals among heart cells. Answer: D 15) It is important that the atrioventricular (AV) node produce a delay between the contraction of the atria and the contraction of the ventricles because this allows the A) heart to rest for a brief period of time. B) atria to contract in smooth synchrony. C) ventricles to contract in smooth synchrony. D) ventricles to fill to capacity. Answer: D 16) An artificial pacemaker is a device that replaces the actions of the A) atria. B) sinoatrial node. C) ventricles. D) atrioventricular node. Answer: B 17) In fishes, blood leaving the heart goes directly to the A) swimming muscles. B) kidney. C) gills. D) brain. Answer: C 18) Which of these animals has a heart with only two chambers? A) Cat B) Goldfish C) Hummingbird D) Human E) Bullfrog Answer: B 19) In mammals, blood with a low oxygen content enters the A) left ventricle B) right ventricle C) left atrium D) right atrium E) aorta Answer: D

of the heart.

20) If a person's blood pressure is 120/70, the 70 refers to the pressure A) lowering between contractions. B) during contraction of the left ventricle only. C) during contraction of the venacava. D) during contraction of both ventricles. E) during relaxation of theheart. Answer: E 21) Ventricles force blood directly into the A) venules. B) arterioles. C) veins. D) arteries. E) capillaries. Answer: D 22) The human heart contains cells that do all of the following EXCEPT A) create new red blood cells. B) respond to signals from the nervous system. C) contract. D) generate electricalsignals. Answer: A 23) The valve is between the right ventricle and the pulmonary artery. A) atrioventricular B) tricuspid C) semilunar D) bicuspid Answer: C 24) What is the cardiac cycle? A) The alternating relaxation and contraction of the heart chambers B) The movement of blood from systemic to pulmonary circulation C) The passage of electrical impulses from the AV node to the SN node to heart muscle D) The movement of blood from the heart to the lungs and then back to the heart Answer: A 25) All of the following are true of the SA node EXCEPT that it A) directly stimulates the ventricles. B) directly stimulates the atria. C) is influenced by nerve impulses and hormones. D) is thepacemaker. Answer: A 26) When your blood pressure is measured from an artery in your arm, it is a measurement of the pressure produced by your A) right atrium. B) left atrium. C) right ventricle. D) left ventricle. Answer: D 4

27) Southern Copperhead snake venom contains a protein called disintegrin. Disintegrins bind to a class of membrane receptors called integrins. Platelets use integrin receptors to aggregate at a site of tissue damage. Why does the snake venom contain this molecule? A) By binding to the platelets, the molecule inhibits the formation of fibrin. B) The molecule helps kill the snake's prey by producing large clots that travel in the body and produce heart attacks and strokes. C) After the snake bites its prey, the molecule helps in wound healing. D) The molecule interferes with clot formation so that the venom can travel more efficiently from the site of the bite to the rest of the body. Answer: D 28) In a random screening of athletes at a recent event, a runner was disqualified for testing positive for an injected form of erythropoietin. Which of the following is a consequence of extra erythropoietin in the circulatory system? A) More red blood cells B) "Thin" blood that does not clotefficiently C) Low blood pressure D) A low white blood cell count Answer: A 29) The most abundant cell type in blood is the A) basophil. B) leukocyte. C) platelet. D) neutrophil. E) erythrocyte. Answer: E 30) Plasma contains all of the following components EXCEPT A) lymph. B) hormones. C) water. D) albumin. Answer: A 31) How many molecules of oxygen can bind with one molecule of human hemoglobin? A) One B) Two C) Three D) Four E) Five Answer: D 32) The average red blood cell lives for about A) 150 B) 100 C) 120 D) 90

days.

Answer: C

33) Erythropoietin A) is released in response to high carbon dioxide or low oxygen levels in the blood. B) stimulates the spleen to release more red blood cells. C) is released only in response to hemorrhaging (bleeding). D) is produced by the pancreas. Answer: A 34) Each of the following types of white blood cells is found within the circulatory system EXCEPT A) monocytes. B) leukocytes. C) macrophages. D) lymphocytes. Answer: C 35) Which blood constituent makes up most of the volume of blood? A) Plasma B) Red blood cells C) White blood cells D) Blood proteins Answer: A 36) Erythrocytes are produced in the A) heart. B) liver. C) bone marrow. D) spleen. Answer: C 37) Plasma is primarily A) gases. B) water. C) protein. D) salt. E) cells. Answer: B 38) Females need more dietary iron than males because they A) have less bone marrow. B) lose more iron (during menstruation). C) have fewer red blood cells. D) eat less red meat thanmales. E) have a smaller volume of blood. Answer: B 39) Long-distance runners like to train at high altitudes because the lack of oxygen there stimulates the A) body to produce more lungtissue. B) muscles to contract faster. C) muscles to contract less strongly. D) capillaries to diffuse oxygen moreslowly. E) bone marrow to make more erythrocytes. Answer: E 6

40) Some athletes use "blood doping," in which additional red blood cells are added to the blood prior to the competition. What is the effect of blood doping? A) It changes the blood type. B) It makes blood thinner so that it flows faster. C) It decreases blood pressure. D) It increases oxygen delivery to muscles. Answer: D 41) White blood cells A) carry oxygen in blood. B) are formed in thespleen. C) clot blood. D) protect the body from microbes. Answer: D 42) Which of the following does NOT play a role in blood clotting? A) Thrombin B) Platelets C) Fibrin D) Albumin E) Fibrinogen Answer: D 43) Which of these blood cells have no nucleus in mammals? A) White blood cells B) Red blood cells C) Lymphocytes D) All blood cells in mammals lack nuclei. Answer: B 44) Erythropoietin stimulates the manufacture of A) red blood cells. B) white blood cells. C) albumin. D) platelets. Answer: A 45) Which of the following includes lymphocytes? A) Platelets B) White blood cells C) Albumin D) Red blood cells Answer: B 46) What is one reason arteries can withstand higher blood pressure than veins? A) Arteries contain all types of blood cells, whereas veins contain only erythrocytes. B) Arteries contain only oxygenated blood. C) Arteries have thick walls that contain layers of muscle and connective tissue. D) Arteries have one-way valves to prevent blood from flowing backward. Answer: C

47) The head of a giraffe is 5 meters above its heart. Compared to humans, giraffes have A) higher systolic blood pressure. B) less blood volume. C) lower systolic blood pressure. D) veins of smaller diameter. Answer: A 48) Plasma that leaks out of the blood in the capillary beds is returned to the venous circulation by A) the lymphatic system. B) the smallintestine. C) suppressor B cells. D) the inflammatory response. Answer: A 49) When your physician takes your pulse, he or she is feeling the expansion and contraction of your A) veins or venules. B) arteries and veins. C) capillaries. D) arteries or arterioles. Answer: D 50) What drives the return of blood to the heart in the systemic veins? A) Ciliated cells lining the inside of the veins B) Muscles squeezing blood through the veins C) The lymphatic system D) Contractions of the left auricle Answer: B 51) What is the correct sequence of blood vessels from the heart through the body and back to the heart? A) Arterioles, arteries, capillaries, veins, venules B) Veins, venules, arteries, arterioles, capillaries C) Arteries, arterioles, capillaries, venules, veins D) Veins, venules, capillaries, arterioles, arteries E) Arteries, arterioles, veins, venules, capillaries Answer: C 52) Which of the following is smallest in diameter? A) Venule B) Arteriole C) Capillary D) Artery E) Veni Answer: C 53) Which of the following has the lowest pressure? A) Capillaries B) Arterioles C) Veins D) Venules E) Arteries Answer: C 8

54) Imagine that you are about to give blood for the first time. While watching other donors around you, you become pale and have to sit down before you faint. Which vessels constricted to produce this nervous side effect? A) Capillaries B) Veins C) Arteries D) Venules E) Arterioles Answer: E 55) Which of the following types of blood vessels are directly involved in the exchange of materials between blood and tissues? A) Arteries B) Arterioles C) Veins D) Capillaries E) Lymphatics Answer: D 56) What happens to the speed of blood as it passes through the capillaries? A) It increases slightly. B) It decreasesgreatly. C) It decreases slightly. D) It increases greatly. E) It depends on the location of the capillaries. Answer: B 57) What is the role of valves in the veins? A) They push the blood back toward the capillaries so that all the oxygen can be removed. B) They slow blood flow in the veins so that the blood can move more slowly in the capillaries. C) They keep blood from flowing backward when the veins are squeezed by skeletal muscles. D) They push the blood upward toward the heart. E) They block the flow of blood to the heart until it has time to contract again. Answer: C 58) The accumulation of carbon dioxide, lactic acid, or other cellular waste causes nearby precapillary sphincters to A) shorten. B) contract. C) relax. D) lengthen. Answer: C 59) Hypertension may lead to A) enlarged prostate. B) lung cancer. C) atherosclerosis. D) low blood pressure. Answer: C

60) Which is the "good" cholesterol? A) HDL B) LDL C) VLDL D) VHDL Answer: A 61) Atherosclerosis A) is caused by a diet high in salt. B) reduces blood flow in arteries. C) causes a loss of plaque from the walls of the arteries. D) is another name for high blood pressure. E) is a condition of the veins. Answer: B 62) How do lymphatic capillaries differ from blood capillaries? A) They contain red blood cells. B) They have "dead ends." C) They contain plasma. D) They have a wall only one cell layer thick. E) They are made by lymphocytes. Answer: B 63) All of the following are true statements about the lymphatic system EXCEPT that A) the lymphatic system returns fluids to the bloodstream. B) the lymphatic system helps defend the body against disease. C) lymphatic vessels resemble veins because they have valves. D) the lymphatic system transports carbohydrates from the small intestine to the blood. Answer: D 64) In an average person, how many liters of interstitial fluid leave the capillaries each day? A) 1 B) 2 C) 12 D) 8 E) 3 to 4 Answer: E 65) Which of the following is delivered from the small intestine to the bloodstream through the lymphatic system? A) Carbohydrates (sugars) B) Amino acids C) Proteins D) Lipids (fats) Answer: D

66) When interstitial fluid enters the lymphatic system, it becomes known as A) globulin. B) plasma. C) interstitial fluid. D) lymph. E) macrophage. Answer: D 67) All of the following are functions of thelymphatic system EXCEPT A) returning fluid to the circulatory system. B) defending the body. C) transporting fats to the circulatory system. D) returning dissolvedmaterials to the circulation. E) transporting oxygen to thelungs. Answer: E 68) What two organs are considered to be part of the lymphatic system? A) Pancreas and liver B) Spleen and thymus C) Thalamus and hypothalamus D) Heart and lungs E) Gall bladder and kidneys Answer: B 69) Fishes have a two-chambered heart, a single atrium, and a single ventricle. A) True B) False Answer: A 70) Platelets are large cells that aid in blood clotting. A) True B) False Answer: B 71) Thrombin catalyzes the conversion of the plasma protein fibrinogen into fibrin. A) True B) False Answer: A 72) Bone marrow is part of the lymphatic system. A) True B) False Answer: A 73) Lymph nodes aid in the destruction of bacteria and viruses. A) True B) False Answer: A

SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 74) The period of time in which the ventricles contract is known as ventricular

Answer: systole 75) While sitting in front of the TV, the average person's heart rate is about 70 beats per minute because the nervous system slows the heart down from the approximately 100 beats per minute that the pacemaker, the node, sets. Answer: sinoatrial (SA) 76) A diagnosis of

(or high blood pressure) is made when blood pressure is higher than 140/90.

Answer: hypertension 77) The fluid portion of the blood is called

Answer: plasma 78) Red blood cells carry oxygen that is attached to a large, iron-containing protein called

Answer: hemoglobin 79) Fluid that leaks (or is pushed out by pressure) from the capillaries into the tissue spaces is known as fluid. Answer: interstitial 80) What is an advantage of closed circulatory systems? Answer: Closed systems allow for more rapid and efficient transport of materials. This is necessary for the survival of large animals with high energy needs. 81) Imagine that you are a red blood cell. Describe your "Trek Through the Heart" from when you enter until you finally exit. (Hint: You enter the right atrium. What next?) Answer: You enter the right atrium and go into the right ventricle. You then get pumped through the pulmonary arteries into the lungs and become oxygenated. You return to the heart via the pulmonary veins and enter the left atrium and then go to the left ventricle. You are then pumped into the aorta and out to the rest of the body. 82) What is the role oferythropoietin? Answer: It simulates the bone marrow to produce erythrocytes (red blood cells). 83) During clotting, what happens to the plasma protein fibrinogen? Answer: It is converted into fibrin, which is a string-like protein that forms a web, trapping red blood cells and platelets. 84) Children who are severely deficient in protein may develop swollen bodies (a condition called kwashiorkor) due to an accumulation of fluid in their tissues. Based on your knowledge of the role of albumin in the blood, explain how this might happen. Answer: Albumin proteins maintain the osmotic balance of the bloodstream. If the fluid that normally leaks out from the capillaries cannot be pulled back in (due to the osmotic "pull" of albumins), tissues will swell as this fluid accumulates.

85) Why is HDL cholesterol considered to be "good" cholesterol? Answer: HDL cholesterol is metabolized or excreted. It helps to remove fatty deposits from the smooth muscles of the arteries and returns these fats to the liver for reprocessing. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 86) Based on this figure, which of the following is TRUE?

A) Deoxygenated blood enters the body capillaries after being pumped from the heart. B) Oxygenated and deoxygenated blood mix in the atria. C) Oxygenated and deoxygenated blood mix in the ventricle. D) Oxygenated and deoxygenated blood never mix. Answer: C

87) Based on this figure, which of the following occurs first?

A) Prothrombin conversion B) Fibrinogen conversion C) Fibrin production Answer: A 88) Rheumatic fever (RF) is an inflammatory disease following infection from Streptococcus bacteria. It mainly affects children between ages 5 and 15 and occurs approximately 20 days after strep throat or scarlet fever. Severe RF can result in degeneration of the heart valves. Based on this scenario, RF is most likely to cause A) uncoordinated contraction of ventricles. B) slower heartbeat. C) "backslide" of blood from a ventricle to anatrium. D) faster heartbeat. Answer: C 89) The liver is the primary producer of albumin. People with liver failure often show signs of extensive edema (tissue swelling). The edema occurs because fluid in the tissues is less likely to return to the blood due to a breakdown in the osmotic gradient that normally exists. Based on this scenario, which of the following statements explains this phenomenon? A) Albumin, which is not normally released by the liver, causes an increase in blood pressure, which forces fluid into the tissues from the capillaries. B) Albumin, which is not normally released by the liver, causes capillaries to become leaky and release fluid into the surrounding tissues. C) The failing liver releases more albumin into the blood than normal. D) The failing liver releases less albumin into the blood than normal. Answer: D

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) All organisms that generate energy (ATP) aerobically need to take in oxygen and remove carbon dioxide from their bodies. This process is known as A) elimination. B) ingestion. C) absorption. D) conduction. E) respiration. Answer: E 2) The carbon dioxide that is exhaled when you breathe is produced during A) glycolysis. B) intracellular digestion. C) diffusion. D) nitrogen fixation. E) cellular respiration. Answer: E 3) Which of the following is NOT a feature shared by all animal respiratory surfaces? A) They are associated with a capillary bed. B) They are moist. C) They are thin. D) They have a large surface area. Answer: A 4) Why does a typical fish die quickly when it is removed from water? A) Gills split water molecules into hydrogen and oxygen, which is used for cellular respiration. B) Water contains more oxygen, per unit volume, than does air. C) The gills collapse and dry out in the air. D) Oxygen diffuses more rapidly in water than it does in air. Answer: C 5) Which of the following structures is NOT part of an insect respiratory system? A) Tracheoles B) Parabronchi C) Tracheae D) Spiracles Answer: B 6) Which of the following groups of animals is most efficient at extracting oxygen from the atmosphere? A) Amphibians B) Birds C) Mammals D) Insects E) Reptiles Answer: B

7) In the lungs, oxygen moves from air into blood by A) active transport. B) osmosis. C) facilitated diffusion. D) diffusion. E) bulk flow. Answer: D 8) If a respiratory surface dries out, gas exchange will A) not occur. B) decrease for oxygen but increase for carbon dioxide. C) decrease for carbon dioxide but increase for oxygen. D) not be affected. E) increase. Answer: A 9) Which of the following structures protects the delicate gills of many fish? A) An operculum B) Lamellae C) Spiracles D) An alveolus E) Tracheoles Answer: A 10) Which of the following statements about gas exchange in animals with interacting circulatory and respiratory systems is FALSE? A) Gases are transported in the circulatory system by the bulk flow of blood. B) Oxygen is actively transported into the circulatory system. C) Air or water moves across the respiratory surface by bulk flow. D) Carbon dioxide moves from the tissues into the blood by diffusion. E) Oxygen and carbon dioxide pass through respiratory membranes by diffusion. Answer: B 11) Which of these animals use gills to respire? A) Spiders B) Tadpoles C) Earthworms D) Insects E) Jellyfishes Answer: B 12) What are spiracles? A) Openings to the bronchi B) Openings into the tracheae ofinsects C) Openings into the alveoli of the lungs D) Openings between the gills of a frog tadpole E) Openings to the parabronchi Answer: B

13) All of the following are respiratory surfaces EXCEPTfor A) tracheae of a fly. B) alveoli of dogs. C) skin of earthworms. D) gills of fish. E) air sacs of birds. Answer: E 14) You are a veterinarian working for the San Diego Zoo. Today, you are performing an autopsy on a 22.7-gram frog and a 21.2-gram lizard, both of which appear to have died of a respiratory infection. Why are you not surprised to find that the lungs of the lizard have a larger internal surface area than those of the frog? A) Lizards are more susceptible than frogs to atmospheric pollutants. B) Lizards have a higher metabolic rate than frogs. C) Lizards have dry, scaly skin, whereas frogs have thin, moist skin. D) The lizard is larger than the frog. E) Lizards lay shelled eggs on land, whereas frogs lay jelly-like eggs in water. Answer: C 15) Identify the animal that lacks a specialized respiratory organ. A) Trout B) Bat C) Grasshopper D) Sponge E) Bird Answer: D 16) Air flow into and out of the lungs is an example of A) facilitated diffusion. B) active transport. C) diffusion. D) osmosis. E) bulk flow. Answer: E 17) Why is gas exchange in an aquatic environment more challenging than gas exchange in the air? A) Less oxygen is available in water than in air. B) Carbon dioxide is eliminated by active transport in an aquatic environment. C) The countercurrent exchange process limits the amount of oxygen that can be extracted from water. D) The large surface area of gills makes them more susceptible to drying out. E) Gills have a poor blood supply. Answer: A 18) Birds are able to sustain long flights at high altitudes because they A) decrease their heart rate during flight. B) can extract oxygen during both inhalation and exhalation. C) have thicker blood than other animals, with many more red blood cells. D) use anaerobic metabolism during flight. E) are able to lower their body temperature during flight. Answer: B

19) Which of the following structures decreases diffusion distances for oxygen and carbon dioxide by delivering air directly to body cells? A) Spiracles B) Bronchi C) Gill filaments D) Tracheoles E) Parabronchi Answer: D 20) Sea jellies lack specialized organs for gas exchange because A) their digestive system eliminates carbon dioxide. B) they use their circulatory system to deliver oxygen to their cells. C) they don't need oxygen. D) their tissues have low energydemands. Answer: D 21) Which of the following organisms would use its skin as a primary respiratory surface? A) Lizard B) Snake C) Bird D) Turtle E) Salamander Answer: E 22) Which sequence of animals represents the evolution of animal respiratory systems? A) Salamander, lizard, fish, bird B) Fish, lizard, salamander, bird C) Lizard, fish, bird, salamander D) Fish, salamander, lizard, bird E) Bird, lizard, salamander, fish Answer: D 23) Which of these structures is analogous in function to the tracheoles of insects? A) Bronchi of a human B) Skin of an earthworm C) Gills of a fish D) Body surface of a flatworm Answer: A 24) Which of these structures is analogous in function to the alveoli of humans? A) Skin of an alligator B) Operculum of a fish C) Trachea of a frog D) Spiracles of a grasshopper E) Parabronchi of abird Answer: E

25) The respiratory systems of fishes, frogs, sponges, and earthworms are similar in that they A) have a countercurrent exchange system. B) exchange gases across a moist respiratory surface. C) have internal respiratory structures. D) utilize a complex network of air-conducting tubes. E) employ an extensive system of air sacs that ensures a unidirectional flow of air. Answer: B 26) Which of the following structures is the site of gas exchange in the human lung? A) Larynx B) Trachea C) Bronchioles D) Alveoli E) Bronchi Answer: D 27) What structure prevents food from entering the larynx? A) Intercostal muscle B) Diaphragm C) Respiratory membrane D) Epiglottis E) Bronchus Answer: D 28) The vocal cords are located in the A) trachea. B) pharynx. C) larynx. D) epiglottis. E) bronchi. Answer: C 29) Gas exchange in the lungs occurs as a result of A) diffusion of gases between the blood and the alveolus. B) active transport of gases between the blood and the alveolus. C) facilitated diffusion of gases between the blood and the alveolus. D) facilitated diffusion of gases between the hemoglobin and the alveolus. E) active transport of gases between hemoglobin and the alveolus. Answer: A 30) Which of the following represents the correct air pathway during exhalation? A) Trachea, larynx, bronchi, alveoli, bronchioles B) Larynx, trachea, bronchi, bronchioles, alveoli C) Alveoli, bronchioles, bronchi, larynx, trachea D) Bronchioles, bronchi, alveoli, trachea, larynx Answer: C

31) Most of the carbon dioxide released from cells is transported in the blood as A) dissolved carbon monoxide. B) carbon dioxide attached to hemoglobin. C) bicarbonate ions in the plasma. D) carbohydrates, such as glucose. Answer: C 32) During inhalation, the diaphragm A) relaxes and flattens. B) contracts and becomes dome-shaped. C) relaxes and becomes dome-shaped. D) contracts and flattens. Answer: D 33) How much air enters the lungs of an average-sized adult when breathing normally? A) 275 milliliters B) 750 milliliters C) 500 milliliters D) 125 milliliters E) 1,000 milliliters Answer: C 34) The respiratory control center is located in the A) medulla. B) hypothalamus. C) cortex. D) spinal cord. E) diaphragm. Answer: A 35) The function of the epiglottis is to A) facilitate gas exchange in thelungs. B) prevent food from entering the larynx. C) keep the bronchi from collapsing. D) assist the vocal cords in sound production. E) produce surfactant. Answer: B 36) During inhalation, air leaving the nasal cavity passes into the A) pharynx. B) larynx. C) bronchioles. D) trachea. E) bronchi. Answer: A

37) Alveoli A) are blind sacs that extend from tracheae. B) are not permeable to dissolvedoxygen. C) have a moist surface. D) are thick-walled. E) are found ingills. Answer: C 38) A thin slice of lung tissue looks like a cross-section of A) a carrot. B) a blown-up balloon. C) a ball of worms. D) a piece of wood. E) a sponge. Answer: E 39) The cells that line the human respiratory passageways secrete A) mucus. B) blood. C) hormones. D) water. E) enzymes. Answer: A 40) Most of the oxygen in the blood is transported A) as bicarbonate ions. B) combined with carbon dioxide. C) in the plasma. D) by white blood cells. E) bound to hemoglobin. Answer: E 41) Hemoglobin is a respiratory protein. Its function is to A) remove toxins from plasma. B) increase the oxygen-carrying capacity of blood. C) attract lymphocytes to damaged tissues. D) provide structural integrity to red blood cells. E) assist in blood clotting. Answer: B 42) What causes smoker's cough? A) Carbon monoxide in the smoke triggers the cough reflex. B) Smoking affects the respiratory center neurons in the medulla. C) Smoking damages the cilia that normally remove debris-laden mucus. D) Nicotine irritates the lining of the lung. Answer: C

43) An emergency room physician has withdrawn blood from a vessel in your arm. The dark red color of the blood indicates that it was A) coming from the lungs. B) taken from a vein. C) going away from the heart. D) taken from an artery. E) on its way to the tissues of the arm. Answer: B 44) The respiratory membrane is a combination of A) bronchi and air sacs. B) bronchioles and capillary walls. C) bronchi andbronchioles. D) bronchioles and air sacs. E) alveolar and capillarywalls. Answer: E 45) What is the function ofsurfactant? A) It enhances contraction of the inspiratory muscles. B) It increases alveolar expansion. C) It stimulates activity of the cilia lining the walls of the alveoli. D) It prevents the alveoli from sticking together and collapsing. E) It increases surface tension. Answer: D 46) Which of the following occurs in the lungs? A) Gases move by bulk flow into and out of the blood. B) Air loses all of its oxygen. C) Some of the oxygen in the air moves into the blood, and some of the carbon dioxide in the blood moves into the air. D) As oxygen-poor blood travels through the lungs, it releases all of its carbon dioxide. E) Oxygen and carbon dioxide move from a lower concentration to a higher concentration. Answer: C 47) What happens during inhalation? A) Air exits the alveoli. B) The diaphragm contracts. C) The intercostal muscles relax. D) The heart pumps blood to the lungs. E) The chest cavity decreases in size. Answer: B 48) The respiratory control center consistsof A) the alveoli. B) a group of highly modified cells located in the hypothalamus. C) a cluster of nerve cells in the medulla. D) the anterior portion of the pituitary gland. E) a cluster of nerve cells in the lungs. Answer: C

49) All of the following are possible EXCEPT A) a voluntary increase in the rate of breathing. B) inhibition of the respiratory centers in the brain. C) voluntarily holding one's breath until death occurs. D) an involuntary increase in the rate of breathing. E) a voluntary decrease in the rate of breathing. Answer: C 50) The respiratory center is very sensitive to changes in levels. A) temperature; blood pressure B) oxygen; carbon dioxide C) blood sugar; hormone D) hormone; blood sugar E) carbon dioxide; oxygen

levels, but not very sensitive to changes in

Answer: E 51) Imagine that a patient is admitted to the hospital after falling from the second-story window of her apartment. Tests reveal no injuries other than some swelling in the brain. Why, then, would her breathing become irregular? A) The damage to the brain is affecting the respiratory center in the medulla. B) The respiratory center in the lungs is malfunctioning due to a lack of carbon dioxide. C) Her tissues require more oxygen for healing. D) Her swollen brain is causing a decrease in blood pressure. E) The blood returning to the lungs from the brain is too high in oxygen. Answer: A 52) Carbon dioxide can be transported in the blood by all of the following methods, EXCEPT A) bound to hemoglobin. B) dissolved in plasma as CO2. C) carried in plasma as HCO3-. D) as CO within red blood cells. Answer: D 53) Which of the following is NOT part of the conducting portion of the human respiratory system? A) Larynx B) Alveoli C) Trachea D) Bronchi E) Pharynx Answer: B 54) Which of the following events initiates the process of exhalation? A) Expansion of the lungs B) Contraction of the intercostal (rib) muscles C) Relaxation of the diaphragm D) Contraction of the diaphragm Answer: C

55) The receptors in the respiratory center are most sensitive to a small A) increase in blood carbon dioxidelevels. B) decrease in blood oxygen levels. C) increase in blood oxygen levels. D) decrease in blood nitrogen levels. E) increase in blood pH. Answer: A 56) Which of the following passageways delivers air directly into each lung? A) Bronchus B) Trachea C) Bronchiole D) Pharynx E) Larynx Answer: A 57) Which of the following structures serves as a passageway for both air and food? A) Larynx B) Bronchioles C) Pharynx D) Trachea E) Bronchi Answer: C 58) A layer of smooth muscle in the wall of this tiny air-conducting tube allows it to regulate its diameter. A) Pharynx B) Alveolus C) Bronchiole D) Trachea E) Larynx Answer: C 59) Where does gas exchange occur in the mammalian lung? A) Alveoli B) The pharynx C) The trachea D) Bronchioles E) Bronchi Answer: A 60) What keeps the trachea from collapsing? A) Semicircular rings of cartilage B) Surfactant C) Cilia D) Surface tension of water Answer: A

61) For smokers who quit smoking, when does healing begin? A) After 5 years B) After a year C) Almost immediately D) After 6 months Answer: C 62) Smoker's cough is the result of A) dehydration of respiratory passages. B) emphysema. C) an accumulation of mucus. D) nicotine exposure. E) carbon monoxide irritation in the throat. Answer: C 63) Which of the following is a consequence of breathing secondhand smoke? A) Nonsmoking children of smokers are more likely to contract pneumonia. B) Nonsmoking spouses of smokers have a 30% lower risk of heart attack. C) Nonsmoking children of smokers are less likely to develop atherosclerosis. D) Smokers are more likely to have increased lung capacity. Answer: A 64) What happens during countercurrent exchange in fishes? A) Gas exchange occurs as blood and water move in the same direction across a respiratory surface. B) Oxygen enters the blood by diffusion, and carbon dioxide exits the blood by active transport. C) Gas exchange occurs as blood and water move in opposite directions across a respiratory surface. D) Oxygen and carbon dioxide move in opposite directions across the respiratory surface by facilitated diffusion. E) Oxygen enters the blood by active transport, and carbon dioxide exits the blood by diffusion. Answer: C 65) Fish gills consist of a series of A) parabronchi. B) filaments. C) interconnected bronchioles. D) opercula. E) spiracles. Answer: B 66) All flatworms use their skin as a respiratory organ. A) True B) False Answer: A 67) The surface area of all respiratory systems must be large compared with the size of the animal involved because diffusion is a relatively slowprocess. A) True B) False Answer: A

68) Vertebrate lungs probably evolved from simple outpocketings of the digestive tract of a freshwater fish. A) True B) False Answer: A 69) Some fishes can extract 80% of the oxygen from water flowing through their gills through countercurrent exchange. A) True B) False Answer: A 70) Gills are respiratory structures found in fish, nudibranch mollusks, and some amphibians. A) True B) False Answer: A 71) Most carbon dioxide is transported in red blood cells bound to hemoglobin. A) True B) False Answer: B SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 72) When a cell is active, the levels of carbon dioxide are gas to diffuse out of the cell.

inside the cell than outside the cell, causing the

Answer: higher 73) The cells of cnidarians use relatively little energy, so their demand for oxygen is quite low. They deliver oxygen to their internal cells by pumping water into and out of a central chamber called the . Answer: gastrovascular cavity 74) When a bumblebee lands on a flower, it pumps its abdomen up and down to move oxygen into its system of tracheae through the round openings called on its abdomen. Answer: spiracles 75) In humans, the respiratory rate is primarily regulated by levels of nerve cells in the respiratorycenter.

in the blood, which is detected by

Answer: carbon dioxide 76) During gas exchange inthe lungs, diffuses from the alveoli into the bloodstream capillaries, and diffuses from the bloodstream capillaries into the alveoli. Answer: oxygen; carbon dioxide 77) What structures make up the large surface area for gas exchange in fishes? Answer: There are many gills, each of which is made up of many filaments that are covered by thin folds of tissue called lamellae. 78) What three features are common to all respiratory systems? Answer: All systems are moist and thin and have a large surface area for gas exchange.

79) How can a sponge deliver oxygen to every cell of its body without a respiratory system? Answer: A sponge uses ciliated cells to draw water into its porous body, bringing oxygen and nutrients to its cells while also removing waste and carbon dioxide. 80) How are cellular respiration and organismal respiration related? Answer: Cells carry out cellular respiration, which uses oxygen and produces carbon dioxide. Oxygen is supplied to the cells, and carbon dioxide is removed from the cells by organismal respiration. 81) How do bulk flow and diffusion interact to enable respiratory systems to deliver oxygen quickly to all cells of the body? Answer: Bulk flow carries oxygen quickly into the system and through the circulation to the cells. Diffusion, a slower process, then only has to move oxygen into the circulation and into the cells. 82) The operculum of fishes covers the gills, protecting them from damage and predators. What additional functions does the operculum have? Answer: It streamlines the body and keeps water moving over the gills. 83) How are birds able to get fresh air even when they are exhaling? Answer: Birds have posterior air sacs that fill with air during inspiration and empty into the lungs during exhalation. This supplies oxygen to the lungs continuously, even when birds are exhaling. 84) Describe how fishes are able to extract oxygen from water. Answer: Countercurrent exchange occurs as water flows over the gill filaments. This ensures that the incoming water is always flowing past capillaries with a lower oxygen concentration. 85) What effect does smoking have on the movement of mucus in the respiratory tract? Answer: Smoke paralyzes the cilia so that the mucus cannot be swept upward. 86) What stimulates the respiratory center to increase the breathing rate? Answer: A rise in carbon dioxide levels 87) Compare the way most oxygen is carried in the blood with the way most carbon dioxide is carried. Answer: Most oxygen is bound to hemoglobin; most carbon dioxide is carried as bicarbonate ion, with small amounts bound to hemoglobin and dissolved in the plasma. 88) How is the diffusion of oxygen and carbon dioxide related to their concentration gradients? Answer: Oxygen and carbon dioxide molecules always move from areas of higher concentration to areas of lower concentration. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

89) Based on this figure, which of the following contains the most oxygen?

A) Blood leaving the right ventricle B) Blood entering the left atrium C) Blood entering the alveoli D) Blood leaving the tissues Answer: B

90) Refer to this figure to determine which of the following statements is correct.

A) Blood and water are flowing in opposite directions (countercurrent). B) Blood and water are flowing in the same direction (concurrent). C) Lamellae bring air within diffusing distance of each body cell. D) Oxygen diffuses out of blood as it flows through lamellae. Answer: A 91) Horsehair worms, in the phylum Nematomorpha, do not have a respiratory system. They are usually found in puddles of water or on damp sidewalks and patios, or they may come wiggling out of insects. These creatures have no economic importance other than being parasitic to some insects. Based on this scenario, horsehair worms are most likely to A) be unable to efficiently digest food. B) have a large surface area compared with their volume. C) have a dry skinsurface. D) have very thick bodies. E) use large amountsof energy. Answer: B

92) Cystic fibrosis (CF) is a disease caused by a mutation in a gene called the cystic fibrosis transmembrane conductanceregulator (CFTR). The mutation causes the afflicted individual to produce thick, sticky mucus that the cilia lining the respiratory tract can't easily remove. There is no cure for CF, and most individuals suffering from this condition die in their 20s or 30s. Based on this scenario, what would you conclude about people who have CF? A) They have extremely thin skin that is easily damaged. B) They have excessive growth rates that result in gigantism. C) They have dangerously high blood pressure. D) They suffer from incessant coughing and chronic lung infections. E) They have elevated oxygen levels in their blood. Answer: D

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) An anorexic person A) eats very little food. B) has a bacterial infection in the stomach. C) is usually overweight. D) eats a meal and thenvomits. E) is usually treated withantibiotics. Answer: A 2)

An essential nutrient is one that A) is used for energy storage. B) cannot be made by the organism. C) is required in large amounts. D) can be found only in animal products. Answer: B 3) Which nutrients provide energy foranimals? A) Carbohydrates, fats, and proteins B) Carbohydrates and proteins C) Carbohydrates and fats D) Fats and proteins E) Carbohydrates, fats, and nucleic acids Answer: A 4) The average human body at rest burns about A) 1 B) 500 C) 1,000 D) 5,000 E) 70

Calories per hour.

Answer: E 5) Which of the following vitamins is an essential nutrient in humans that cannot be synthesized by intestinal bacteria? A) Folic acid B) Vitamin C (ascorbic acid) C) Vitamin K D) Biotin E) Vitamin B5 (pantothenic acid) Answer: B 6) Minerals required for bone formationinclude A) iron and sodium. B) calcium and phosphorus. C) calcium and zinc. D) calcium and sodium. E) zinc and potassium. Answer: B

7) Which nutrient is synthesized and stored in the liver and muscles of animals and is used as a source of quick energy? A) Protein B) Glycogen C) Calcium D) Fat E) Starch Answer: B 8) Sodium and potassium are minerals that are important in A) the production of hemoglobin. B) muscle contraction and nerve impulse conduction. C) blood clotting. D) the development of strong bones and teeth. E) the replication of DNA. Answer: B 9) The symptoms of pellagra are due to a lack of A) thiamin. B) riboflavin. C) pantothenic acid. D) niacin. E) pyridoxine. Answer: D 10) A lack of ascorbic acid (vitamin C) in the diet causes A) anemia. B) pellagra. C) beriberi. D) scurvy. E) acne. Answer: D 11) Vitamin K is required for A) energy metabolism. B) proper kidney function. C) blood clotting. D) night vision. E) collagen synthesis. Answer: C 12) Vitamin D is added to milk because it increases A) iron absorption. B) digestion of milk protein. C) digestion of lipids in milk. D) the shelf life of milk. E) calcium absorption. Answer: E

13) Women who become pregnant are encouraged to take supplements of nutrient can cause birth defects. A) vitamin C B) choline C) vitamin K D) biotin E) folic acid

because a deficiency in this

Answer: E 14) The ability of the blood to transport oxygen is greatly reduced in individuals who have a dietary deficiency of this mineral. A) Calcium B) Potassium C) Zinc D) Iron E) Sodium Answer: D 15) The amount of energy needed to raise the temperature of 1 gram of water by 1°C is called A) the body mass index. B) a calorie. C) a Calorie. D) the resting metabolic rate. E) the basal energyquotient. Answer: B 16) A

person has the highest energy expenditure at rest. A) moderately sedentary B) moderately physically active C) very sedentary, overweight D) very physically active, muscular

Answer: D 17) Which of the following nutrients would yield the most energy per gram? A) Vitamins B) Lipids C) Minerals D) Carbohydrates E) Proteins Answer: B 18) You eat 25 potato chips, which contain 10 grams of carbohydrate (potato) and 10 grams of fat. This means that A) about 40 Calories are from fat and 90 Calories are from carbohydrate. B) all of the calories are from fat. C) about half your calories are from fat and half from carbohydrate. D) about 90 Calories are from fat and 40 Calories are from carbohydrate. E) all of the calories are from carbohydrate. Answer: D

19) Which of the following help neutralize free radicals that form in the body? A) Minerals B) Monosaccharides C) Antioxidants D) Lipids E) Amino acids Answer: C 20) All of the following statements regarding proteins are true EXCEPT A) humans can synthesize all of the amino acids needed to make proteins. B) most enzymes are proteins. C) they are the primary components of muscle, connective tissue, nails, and hair. D) kwashiorkor is caused by proteindeficiency. E) some act as receptors on cell membranes. Answer: A 21) What is the primary energy-storage molecule in plants? A) Protein B) Chlorophyll C) Starch D) Cholesterol E) Cellulose Answer: C 22) You awaken to discover your alarm clock failed to ring. You just might be able to make it to class on time if you leave immediately (skip breakfast) and sprint to reach the lecture hall two blocks away. What energy source is most likely being used to fuel your activity? A) Glycogen B) Fat C) Protein D) Cellulose E) Phospholipid Answer: A 23) Your roommate tells you that because she has no time to eat healthy foods, she is taking megadoses of vitamins. You warn her that this may be dangerous, because certain vitamins can accumulate in body fat. Megadoses of which of the following vitamins would be most likely to cause toxic effects? A) Vitamin C B) Thiamin C) Vitamin E D) Folic acid Answer: C 24) Which vitamin plays a major role in blood clotting? A) B1 (thiamin) B) K C) D D) A E) B12 Answer: B

25) When your mother told you to drink your milk because it would help build strong bones, she was A) wrong, because milk contains large amounts of vitamin E, which helps with the formation of red blood cells. B) wrong, because milk contains large amounts of vitamin D, which causes rickets. C) wrong, because milk contains large amounts of vitamin C, which causes scurvy. D) right, because milk contains vitamin D, which promotes bone growth. E) right, because milk contains vitamin C, which is involved in maintaining the walls of blood vessels in the retina. Answer: D 26) Which of the following is a water-soluble vitamin? A) A B) C C) D D) E E) K Answer: B 27) With the widespread public interest in low-fat food, some companies have started to use synthetic fats that cannot be broken down and absorbed by the digestive system. What problem might be associated with a typical American diet that includes large amounts of these synthetic fats? A) Obesity B) Anorexia C) Vitamin C deficiency D) Vitamin K deficiency E) Protein deficiency Answer: D 28) Sea anemones, hydra, and sea jellies digest food extracellularly within a A) rumen. B) lysosome. C) gastrovascular cavity. D) food vacuole. E) digestive tract. Answer: C 29) Wolves, seals, and cats have enlarged canines and molars designed for shearing rather than grinding or chewing. How would you classify these animals on the basis of the type of teeth they possess? A) Herbivores B) Omnivores C) Carnivores D) Ruminants Answer: C

30) Which of the following best describes the process of bringing food into the digestive system through an opening? A) Ingestion B) Indigestion C) Digestion D) Adsorption E) Absorption Answer: A 31) Which of these animals uses collar cells to obtain food for intracellular digestion? A) Humans B) Sponges C) Earthworms D) Protists E) Hydra Answer: B 32) In most animals, digestion occurs A) intracellularly, through collar cells. B) extracellularly, within the circulatory system. C) intracellularly, through simple absorption. D) extracellularly, within a gastrovascular cavity. E) extracellularly, within a cavity that is open at both ends. Answer: E 33) All of the following structures are found in the digestive system of birds EXCEPT a(n) A) abomasum. B) small intestine. C) esophagus. D) crop. E) gizzard. Answer: A 34) How would you classify an organism that consumes and digests both plant and animal sources of nutrients? A) Omnivore B) Carnivore C) Ruminant D) Herbivore Answer: A 35) Which of the following statements is TRUE regarding a gastrovascular cavity? A) Digestion is unnecessary because of the small size of the particles absorbed. B) Ingestion and elimination occur through a single opening. C) Absorption occurs within collar cells. D) Digestion is exclusively intracellular. E) Digestion occurs in specialized chambers. Answer: B

36) Ruminants A) have a two-chambered stomach. B) have a very short small intestine. C) rely on a muscular gizzard to grind their food. D) are obligate meat-eaters, or carnivores. E) harbor symbiotic microorganisms that digest cellulose. Answer: E 37) Which of the following produces the cellulose-digesting enzyme (cellulase) in a cow's digestive tract? A) Microorganisms in the rumen B) Gallbladder C) Pancreas D) Cells lining the small intestine E) Liver Answer: A 38) A shipworm is an animal that subsists entirely on a diet of wood. What digestive feature is this animal likely to have in order to survive on this highly specialized diet? A) Intracellular digestion B) A three-chambered stomach C) Large amounts of proteases andlipases D) A gastrovascular cavity E) Symbiotic microorganisms that produce cellulose-digesting enzymes Answer: E 39) Which of the following contains indigestible fiber, mucus, and dead microorganisms that are eliminated from the body? A) Pancreatic juice B) Feces C) Bile D) Chyme E) Ghrelin Answer: B 40) Which part of the digestive tract has the lowest pH? A) Rectum B) Small intestine C) Large intestine D) Pancreas E) Stomach Answer: E 41) What type of digestion takes place inside the mouth? A) Chemical digestion only B) Ingestion only C) Mechanical digestion only D) Mechanical and chemical digestion E) Absorption only Answer: D

42) Amylase is produced by the A) salivary glands and pancreas. B) pancreas only. C) salivary glands only. D) salivary glands, small intestine, andpancreas. E) small intestine only. Answer: A 43) Most chemical digestion occurs inthe A) esophagus. B) small intestine. C) mouth. D) large intestine. E) stomach. Answer: B 44) Bile aids in fat digestionby A) acting directly as a lipid-digestingenzyme. B) converting lipids to proteins, which can then be digested by proteases. C) removing the fatty acid chains from the glycerol. D) breaking fat into small fat droplets that can then be digested by enzymes. Answer: D 45) Which of the following can be absorbed directly into the bloodstream? A) Polysaccharides B) Triglycerides C) Amino acids D) Fats E) Large proteins Answer: C 46) Bacteria in the large intestine are able to manufacture A) vitamin K. B) vitamin A. C) vitamin C. D) some minerals. Answer: A 47) Which of the following is responsible for stimulating the release of pancreatic juice into the small intestine? A) Pepsin B) Cholecystokinin C) Ghrelin D) Gastrin E) Leptin Answer: B

48) Digestion begins in the A) stomach. B) mouth. C) pharynx. D) colon. E) small intestine. Answer: B 49) If you chew on a piece of bread long enough, it will begin to taste sweet because A) amylase is breaking down starches into disaccharides. B) disaccharidases are forming glucose. C) lipases are forming fatty acids. D) proteases are forming amino acids. E) maltase is breaking down maltose. Answer: A 50) What structure prevents swallowed material from passing into the larynx? A) Pharynx B) Pyloris C) Tongue D) Epiglottis E) Glottis Answer: D 51) The stomach differs from the small intestine in that it A) has tiny projections called villi that are folded into microvilli. B) produces enzymes that work best at a low pH. C) secretes hormones that travel through the bloodstream. D) secretes enzymes. E) does not secretemucus. Answer: B 52) Which of the following regions of the digestive tract exhibits segmentation movements as well as peristalsis? A) Stomach B) Rectum C) Anus D) Esophagus E) Small intestine Answer: E 53) Which of these enzymes catalyzes the breakdown of starch (a polysaccharide)? A) Peptidase B) Lipase C) Pepsin D) Bile E) Amylase Answer: E

54) The pH of the digestive tract is A) acidic in the stomach and neutral in the intestines. B) high throughout. C) neutral throughout. D) low throughout. E) basic in the stomach and acidic throughout the rest of the tract. Answer: A 55) Which of the following plays a key role in the absorption and distribution of fats? A) Microvilli and villi B) Chylomicrons and lacteals C) Large intestine and rectum D) Secretin and gastrin E) Segmentation and peristalsismovements Answer: B 56) Which hormone stimulates the activity of gastric glands? A) Gastrin B) Secretin C) Pepsinogen D) Cholecystokinin Answer: A 57) Which of the following is a gastric enzyme that breaks down proteins into peptides? A) Lipase B) Amylase C) Bile D) Pepsin E) Sodium bicarbonate Answer: D 58) The major function of the large intestine is to A) neutralize chyme. B) make bile. C) digest food. D) reabsorb water. E) produce digestive enzymes. Answer: D 59) Bile is produced by the liver and stored in the gallbladder. The function of bile is to A) prevent regurgitation of food into the esophagus and activate stomach acids. B) dissolve salts and detoxify poisons in food. C) lower the pH of thestomach. D) disperse fats into smaller particles. E) raise the pH of chyme as it enters the small intestine. Answer: D

60) The cells lining the small intestine have projections into the lumen of the intestine. These projections, combined with the highly folded layering of cells lining the lumen, function to A) slow the nerve impulses that trigger peristalsis. B) facilitate countercurrent exchange. C) increase the surface area for nutrient absorption. D) increase the rate of peristalsis. E) decrease the reabsorption of water. Answer: C 61) Digested fatsare packaged into , which are too big to enter blood capillaries and so have to diffuse into lacteals, where fats enter the lymph and are transported within the lymphatic system. A) chyme B) lipases C) bile salts D) chylomicrons E) micelles Answer: D 62) The activity of which of the following digestive enzymes will be affected by the regular consumption of antacids following a meal? A) Amylase B) Pepsin C) Cellulase D) Sucrase E) Lipase Answer: B 63) Which of these dietary changes should I make following surgery to remove my gallbladder? (Hint: How does the gallbladder assist in digestion?) A) Decrease my consumption of protein B) Increase my intake of water C) Increase my consumption of fats D) Decrease my consumption of fats E) Increase my consumption of protein Answer: D 64) Which of the following structures has both a digestive and a respiratory role? A) Stomach B) Nose C) Larynx D) Esophagus E) Pharynx Answer: E

65) A 50-year-old woman visits her doctor with complaints of bruises that will not heal. Her doctor has had her on long-term antibiotic treatment to control some chronic infections. Which of the following explains how her antibiotic treatment is related to her bruising? A) She is malnourished because the antibiotics have destroyed the "good" bacteria in her digestive system that are responsible for producing the digestive enzymes that she needs to break down her food. B) The antibiotics have destroyed the "good" bacteria in her large intestine that produce vitamin K, which is important for proper blood clotting. C) The antibiotics weaken the cells lining her capillaries, causing them to leak blood into the surrounding tissues. D) The antibiotics have traveled to her liver and are now preventing the liver from producing proteins that circulate in the blood and help with clotting. Answer: B 66) How does the highly acidic fluid in the stomach become slightly basic almost immediately upon entry into the small intestine? A) The acids in this fluid remain in the stomach and only the partially digested food enters the small intestine. B) The acids in this fluid are neutralized by the amylase secreted from the pancreas. C) The acids in this fluid are neutralized by the sodium bicarbonate secreted from the pancreas. D) The acids are absorbed by the small intestine as soon as they leave the stomach. Answer: C 67) Imagine you are a family physician. You see an 18-year-old with a lower-than-normal body weight and teeth that have been eroded by acid. Your diagnosis is A) pancreatitis. B) ulcer of the small intestine. C) liver failure. D) anorexia. E) bulimia. Answer: E 68) The bacterium shown to be associated with the majority of gastric ulcers is A) Helicobacter pylori. B) Escherichia coli. C) Staphylococcus aureus. D) Streptococcus pyogenes. E) Streptococcus lactis. Answer: A 69) Fats and oils contain more energy per gram than proteins or carbohydrates. A) True B) False Answer: A 70) Humans are able to synthesize all the vitamins they need. A) True B) False Answer: B

71) Cellulose is the most abundant carbohydrate on Earth. A) True B) False Answer: A 72) Birds ingest sand or small stones to aid in digestion. A) True B) False Answer: A 73) Digestion in humans occurs in a gastrovascular cavity. A) True B) False Answer: B 74) The small intestine is the principal site of both digestion and nutrient absorption. A) True B) False Answer: A 75) The large intestine is the longest part of the digestive tract. A) True B) False Answer: B SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 76) You need the mineral

in your diet in order to carry oxygen efficiently in your red blood cells.

Answer: iron 77) Hydrochloric acid formed in the stomach converts pepsinogen into pepsin, which enables the stomach to begin digesting . Answer: proteins 78)

digestion is the process by which food particles are exposed to enzymes that break them down into smaller subunits. Answer: Chemical

79) Bile is madeby the

Answer: liver 80) When you swallow, you set in motion a series of wavelike muscle contractions that are collectively called . Answer: peristalsis 81) Name the six major categories of animal nutrients. Answer: lipids, carbohydrates, proteins, minerals, vitamins, and water

82) Briefly discuss the major advantages of fats as energy-storage molecules. Answer: Fats are the most concentrated energy source among all types of nutrients, are hydrophobic (so they prevent excess accumulation of fluids in the tissues), and are able to store more calories with less weight. 83) List the five tasks of all digestive tracts. Answer: ingestion of food, mechanical breakdown of food, chemical breakdown of food, absorption of food nutrients, and elimination of wastes 84) Describe the specialized digestive system that enables ruminants, such as cows, to live on a diet of grass. Answer: Ruminants have a multichambered stomach that houses microorganisms that can break down difficult-todigest carbohydrates, such as cellulose. Also, they regurgitate their food after it has been partially digested and "ruminate" it for further mechanical breakdown, then return it to the stomach for further chemical digestion. 85) Explain how the teeth of carnivores, omnivores, and herbivores differ. Answer: Teeth of carnivores have reduced incisors and enlarged canines. Teeth of herbivores have reduced canines; incisors adapted to snipping leaves; and wide, flat premolars and molars for grinding plant fibers. Omnivores are similar to herbivores but have pointed canines and flat incisors. 86) If you take an antibiotic by mouth for a long period of time, you may become deficient in certain vitamins. How can this be true? Answer: The antibiotic kills off the normal bacteria in the large intestine. Because many of these bacteria make important vitamins that are absorbed by the body, eventually vitamin deficiencies are possible. 87) Briefly describe the role of the liver in the digestion of fat. Answer: The liver produces bile salts, which are stored in and released from the gallbladder. Bile salts act as detergents to disperse fats into microscopic particles, which can be absorbed through the lacteal of the villus and into the circulatory system. 88) Explain why pancreatic juice is important in the digestive process. Answer: Pancreatic juice neutralizes the acidity of chyme and contains the amylases, lipases, and proteases necessary for the digestion of starch, fat, and protein.

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 89) Based on the nutritional label in this figure, which of the following is needed in the greatest quantity (or activity) to thoroughly digest this food?

A) Bile B) Proteases C) Peptidases D) Carbohydrate-digesting enzymes E) Lipases Answer: D

90) This figure illustrates the lining of the

A) esophagus. B) small intestine. C) stomach. D) large intestine. E) pharynx. Answer: B 91) Different species of animals have very different nutritional requirements and gastrointestinal tract (GIT) specializations, depending on their primary diets. For example, carnivorous animals have relatively short small intestines, fast gut passage rates, and high protein requirements, in accordance with the high-protein, easily digested prey they consume. Based on your knowledge of nutrition and digestion and on the example provided in this scenario, what do you conclude about ruminants, which eat low-protein, difficult-to-digest plant leaves? A) They have normal nutritional requirements but extremely short GITs and fast gut passage rates to maximize the amount of food passing through the GIT. B) Their GITs and nutritional requirements are similar to those of carnivores, and they must also eat some animal prey to obtain enough dietary protein. C) They have reduced protein requirements, long GITs, and slow gut passage rates to extract as many nutrients as possible from theirdiet. D) They have reduced protein requirements but GITs and gut passage rates similar to those of carnivores. Answer: C 92) Cancer patients who receive radiation treatment or chemotherapy often slough off their most rapidly dividing body cells, such as those in the hair follicles and those lining the gastrointestinal tract. This results in much of the pain, fatigue, and other complications associated with the cancer treatment. Understandably, some loss of hair is expected when undergoing such procedures. Which of the following would you also expect to occur with cancer treatment? A) Elevated lipid and glucose levels in the blood B) Reduced nutrient absorption and subsequent weakness C) High blood pressure D) Excess mucus production in theairways E) Constipation due to excessive water reabsorption Answer: B

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Which of the following describes the role of urinary systems in maintaining cellular homeostasis? A) Urinary systems regulate water balance, pH, and the concentrations of ions in body fluids for cells. B) Urinary systems are important for the generation of urea, which cells can use as an energy source when carbohydrates become scarce. C) Urinary systems filter out diseased and damaged cells that can be excreted from the body. D) Urinary systems ensure the delivery of the proper amount of nitrogen to the cells. Answer: A 2) Which of the following nitrogenous waste products is the least toxic, but requires the most energy to produce? A) Urine B) Ammonia C) Uric acid D) Urea Answer: C 3) Nitrogenous waste products, such as urea and uric acid, are primarily formed because of the digestion of A) lipids. B) proteins. C) salts. D) carbohydrates. Answer: B 4) Which of these structures converts highly toxic ammonia into urea, a less toxic form of nitrogenous waste? A) Spleen B) Muscles C) Pancreas D) Liver E) Kidney Answer: D 5) Birds excrete their nitrogenous wastes in the form of A) ammonia. B) uric acid. C) amino acids. D) urea. E) amine groups. Answer: B 6) Which of these structures most closely resembles a vertebrate nephron? A) Nephridium B) Malpighian tubule C) Nephrostome D) Flame cell E) Protonephridium Answer: A

7) Insect urinary systems consist of A) Malpighian tubules. B) flame cells. C) nephridia. D) protonephridia. E) nephrostomes. Answer: A 8) Which of the following has a urinary system that makes use of flame cells? A) Shark B) Mollusk C) Earthworm D) Bird E) Flatworm Answer: E 9) The feces of which of the following would contain a high concentration of uric acid? A) Mollusk B) Insect C) Flatworm D) Bird Answer: B 10) Which type of animal would you dissect to locate a nephridium? A) Insect B) Flatworm C) Reptile D) Bird E) Earthworm Answer: E 11) What is the thin, muscular tube through which urine leaves each mammalian kidney? A) Collecting duct B) Bladder C) Ureter D) Urethra E) Nephron Answer: C 12) What is the basic functional unit of the kidney? A) Glomerulus B) Peritubular capillaries C) Nephron D) Glomerular capsule E) Collecting duct Answer: C

13) The human kidneys are located A) in the chest cavity. B) in the abdominal cavity just above the rectum. C) on either side of theesophagus. D) at about the level of the waist. E) in front of the large intestine. Answer: D 14) You have conscious control over A) the external urethral sphincter. B) the internal urethral sphincter. C) muscles that cause the bladder to contract. D) muscles that propel urine from the kidney to the bladder. Answer: A 15) Which of the following is closest to the external surface of the kidney? A) Collecting ducts B) Renal cortex C) Nephron loops D) Renal medulla E) Renal pelvis Answer: B 16) The funnel-like chamber of the kidney that collects urine is called the A) renal medulla. B) smooth muscle. C) glomerulus. D) renal pelvis. E) renal cortex. Answer: D 17) All of the following are part of the nephron EXCEPT the A) renal medulla. B) glomerular capsule. C) proximal tubule. D) glomerulus. E) nephron loop. Answer: A 18) Which of the following correctly traces the path of urine? A) Renal pelvis → ureter → bladder → urethra B) Renal pelvis → bladder → ureter → urethra C) Ureter → urethra → bladder → renal pelvis D) Renal pelvis → uterus → bladder → urethra E) Renal pelvis → urethra → bladder → ureter Answer: A

19) Which sequence properly describes the flow of filtrate through the nephron? A) Glomerular capsule, proximal tubule, nephron loop, distal tubule, collecting duct B) Proximal tubule, nephron loop, glomerular capsule, distal tubule, collecting duct C) Glomerular capsule, peritubular capillaries, nephron loop, distal tubule, collecting duct D) Glomerulus, peritubular capillaries, renal artery, arteriole, venule, renal vein E) Collecting duct, distal tubule, nephron loop, proximal tubule, glomerular capsule Answer: A 20) Which portion of the nephron receives filtrate from the glomerular capsule? A) Proximal tubule B) Collecting duct C) Nephron loop D) Glomerulus E) Distal tubule Answer: A 21) Which structure collects the water and small dissolved molecules forced out of the bloodstream during the process of filtration? A) Nephron loop B) Proximal tubule C) Distal tubule D) Glomerular capsule E) Glomerulus Answer: D 22) Filtration of the blood occurs when fluid is forced by blood pressure out of the A) nephron loop. B) distal tubule. C) glomerular capsule. D) glomerulus. E) proximal tubule. Answer: D 23) Which sequence properly describes the flow of blood through a kidney? A) Renal artery, incoming arteriole, glomerulus, outgoing arteriole, peritubular capillaries, venule, renal vein B) Glomerulus, peritubular capillaries, outgoing arteriole, renal artery, incoming arteriole, venule, renal vein C) Renal vein, venule, glomerulus, outgoing arteriole, peritubular capillaries, incoming arteriole, renal artery D) Peritubular capillaries, incoming arteriole, glomerulus, glomerular capsule, outgoing arteriole, renal artery Answer: A 24) In what region of the nephron does most secretion take place? A) Distal tubule B) Collecting duct C) Proximal tubule D) Nephron loop E) Glomerulus Answer: C

25) In a healthy kidney, glucose and amino acids are reabsorbed into the blood at which location in the nephron? A) Glomerulus B) Proximal tubule C) Distal tubule D) Ureter E) Nephron loop Answer: B 26) What is the process by which water and nutrients are removed from the filtrate and returned to the blood? A) Secretion B) Filtration C) Excretion D) Elimination E) Reabsorption Answer: E 27) Most reabsorption takes place in what part of the tubule system in the kidney? A) Distal tubule B) Collecting duct C) Glomerular capsule D) Proximal tubule E) Nephron loop Answer: D 28) During reabsorption, organic nutrients and ions are moved by diffusion or active transport from the renal tubule into the A) glomerulus. B) peritubular capillaries. C) incoming arteriole. D) glomerular capsule. E) outgoing arteriole. Answer: B 29) Which of the following explains why a sample of the filtrate taken from the proximal tubule is NOT ideal for conducting a drug test or toxicology screen? A) Some of the toxins and drugs do not enter the filtrate until they are secreted in the distal tubule. B) Only a blood test can detect drugs and toxins because they are too large to enter the kidney tubule system. C) As soon as the toxins and drugs enter the proximal tubule, they are immediately reabsorbed. D) Many of the toxins and drugs are not added to urine until it enters the bladder. Answer: A 30) Hormones regulate reabsorption in which region of the kidney tubule system? A) Glomerular capsule B) Glomerulus C) Proximal tubule D) Distal tubule E) Nephron loop Answer: D

31) In a healthy kidney, which of the following would you NOT expect to find in the filtrate? A) Large proteins B) Water C) Drugs D) Salt E) Glucose Answer: A 32) What is the force that drives glomerular filtration (movement of fluid from the glomerulus to the glomerular capsule)? A) Smooth muscle contraction B) Blood pressure C) pH gradients D) Salt gradients E) Osmosis Answer: B 33) Cellular wastes and excess ions are moved from the blood into nephrons by A) filtration and reabsorption. B) reabsorption only. C) filtration and secretion. D) secretion only. E) filtration only. Answer: C 34) Which of these is normally found in the glomerular filtrate? A) Erythrocytes B) Fat droplets C) White blood cells D) Na+ E) Large proteins Answer: D 35) The composition of urine varies to help maintain homeostasis within the body. With this in mind, which of the following would you NOT expect to find in the urine of a healthy individual? A) Potassium ions B) Hydrogen ions C) Glucose D) Drug metabolites E) Ammonia Answer: C 36) Glomerular filtrate contains many components that need to be reabsorbed (returned to the blood). Which of the following is (are) reabsorbed by osmosis? A) Red blood cells B) Urea C) Water D) Glucose E) Amino acids Answer: C

37) Which of the following is the most likely to be secreted into the renal tubule for excretion? A) Glucose B) Excess Na+ C) Water D) Vitamins E) Amino acids Answer: B 38) Which of the following is NOT a function of the vertebrate urinary system? A) Secreting hormones B) Maintaining blood pH C) Adjusting water and ion concentrations D) Regulating body temperature E) Eliminating cellularwastes Answer: D 39) An average hemodialysis session usually lasts 4 hours and occurs about A) once a month. B) once a week. C) 7 days a week. D) three times a week. E) three times a month. Answer: D 40) Kidney failure or end-stage renal disease is most commonly associated with A) a low-carbohydrate diet. B) a low-protein diet. C) a high-fat diet and low blood pressure. D) diabetes and high blood pressure. E) low blood pressure. Answer: D 41) How much urine does the average adult human excrete per day? A) 250 milliliters (1 cup) B) 1,000 milliliters (1 quart) C) 1,500 milliliters (1.5 quarts) D) 500 milliliters (1 pint) E) 125 milliliters (1/2 cup) Answer: C 42) A person taking antibiotics must take pills several times each day to maintain effective concentrations in the blood. This is because of A) osmoregulation. B) a decrease in angiotensin. C) reabsorption. D) a decrease in antidiuretic hormone. E) secretion. Answer: E

43) What are the two main functions of the nephron loop? A) Creates a high salt concentration in the renal medulla and reabsorbs salt and water B) Creates a high salt concentration in the renal cortex and reabsorbs some salt and water C) Creates a high glucose concentration in the renal cortex and releases extra salt into the filtrate D) Creates a low salt concentration in the renal medulla and reabsorbs salt and water E) Filters cellular wastes from blood in the capillaries and reabsorbs some salt and water Answer: A 44) The descending limb of the nephron loop A) responds to high levels of antidiuretic hormone (ADH) in the blood. B) loses water to the medulla as the filtrate becomes more concentrated. C) is permeable to salt andurea. D) pulls water from the renal medulla to make the filtrate more dilute. E) is not permeable to water. Answer: B 45) The ascending limb of the nephron loop A) is permeable to water. B) pulls salt from the renal medulla to make the filtrate more concentrated. C) is the primary site of tubular secretion. D) is permeable to salt. E) responds to high levels of ADH in the blood. Answer: D 46) Which of these hormones enables us to excrete concentrated urine? A) Aldosterone B) Renal diluting hormone C) Diuretic hormone D) ADH E) Homeostatic hormone Answer: D 47) ADH exerts its effect on which of the following? A) Proximal and distal tubules B) Proximal tubule and nephron loop C) Collecting duct and distal tubule D) Descending portion of the nephronloop E) Collecting duct and proximaltubule Answer: C 48) Which of these animals has the greatest proportion of long-looped nephrons in their kidneys? A) A freshwater fish B) A freshwater mammal, such as a beaver C) A saltwater fish D) A desert mammal, such as a sand rat E) A human Answer: D

49) Long nephron loops correlate with A) urine hypotonic to the blood. B) urine with glucose in it. C) more dilute urine. D) urine isotonic to the blood. E) more concentrated urine. Answer: E 50) You analyze a blood sample taken from a man who survived for 2 days in the desert with no water to drink. Based on your knowledge of kidney physiology, you are not surprised to find that his blood level of ADH is A) zero. B) lower than normal. C) higher than normal. D) normal. Answer: C 51) Water may be reabsorbed from many regions of the nephron; however, which regions can do so only if the blood levels of ADH are elevated? A) Proximal tubule and nephron loop B) Nephron loop and distal tubule C) Proximal and distal tubules D) Distal tubule and collecting duct E) Glomerulus and the glomerular capsule Answer: D 52) What percentage of the water that enters a nephron is reabsorbed into the blood in the absence of ADH? A) 99% B) 25% C) 50% D) 80% Answer: D 53) What effect will increased blood levels of ADH have on blood volume? A) It will increase blood volume. B) Only the plasma (fluid) part of the blood will decrease. C) It will decrease blood volume. D) It will have no effect on blood volume because ADH affects only urine output. Answer: A 54) An animal whose kidneys have a high percentage of long-looped nephrons probably lives in a environment. A) rain-forest B) desert C) saltwater D) freshwater E) seasonally wet Answer: B

55) Which of the following is (are) produced by the kidney and is (are) important in the regulation of blood pressure? A) Erythropoietin B) Aldosterone and ADH C) Renin and angiotensin D) ADH only E) Aldosterone only Answer: C 56) Which of the following hormones increases blood pressure by constricting arterioles all over the body? A) Erythropoietin B) Aldosterone C) ADH D) Angiotensin Answer: D 57) ADH is released into the blood by the A) kidney. B) pituitary gland. C) liver. D) small intestine. Answer: B 58) Which of the following increases the reabsorption of water by inserting aquaporins into the membranes of the distal tubule and collecting duct cells? A) Erythropoietin B) Renin C) Angiotensin D) Aldosterone E) ADH Answer: E 59) How would the kidneys respond to a decrease in blood pH caused by a high protein diet? A) Increased production of renin and ADH B) Increased secretion of both H+ and HCO3C) Increased H+ secretion and HCO3- reabsorption D) Increased HCO3- secretion and H+ reabsorption E) Increased reabsorption of both H+ and HCO3Answer: C 60) Officials associated with international track and field competitions have noted an increase in the number of athletes who use a synthetic form of erythropoietin. Athletes use this drug because it A) stimulates the release of ADH, which then goes on to cause an increase in the number of red blood cells and helps athletes increase their aerobic capacity for an event. B) increases urine output so that they can shed weight just prior to an important competition. C) increases the number of oxygen-transporting red blood cells, which helps athletes increase their aerobic capacity for an event. D) decreases blood pressure so that they can be more focused and relaxed during a competition. Answer: C

61) Why do mammals adapted to dry climates tend to have considerably more long-looped nephrons than those adapted to wet climates? A) So that their blood pressure does not drop to dangerously low levels during periods of drought B) So that a lower concentration of salt can be produced in the interstitial fluid of the kidney medulla, causing less water to be reabsorbed into the capillaries C) So that the wastes can be excreted as uric acid instead of urine D) So that the excess urea they produce as a result of dehydration can be properly filtered by the nephrons and excreted E) So that a higher concentration of salt can be produced in the interstitial fluid of the kidney medulla, causing more water to be reabsorbed into the capillaries Answer: E 62) Which type of fish is more likely to live in an environment that has a lower osmolarity than that of its body fluids? A) Brackish water fish (salt- and freshwater combined) B) Freshwater fish C) Saltwater fish Answer: B 63) Which type of fish stores urea in its tissues to keep its body the same osmolarity as the water in which it lives? A) Shark B) Goldfish C) Trout D) Tuna E) Shrimp Answer: A 64) Osmolarity is the A) ratio of oxygen to carbondioxide. B) pressure within a closed system. C) pH concentration of a solution. D) concentration of dissolved solutes in solution. Answer: D 65) Urea is more toxic to the human body than is ammonia. A) True B) False Answer: B 66) Earthworms utilize Malpighian tubules to conserve water and excrete cellular wastes. A) True B) False Answer: B 67) Flatworms have simple kidneys consisting of tubular structures called nephridia. A) True B) False Answer: B

68) Your entire blood volume is filtered by your kidneys approximately 60 times per day. A) True B) False Answer: A 69) The composition of glomerular filtrate is almost identical to that of urine. A) True B) False Answer: B 70) The glomerulus, like all other capillary beds, empties into a venule. A) True B) False Answer: B 71) People whose kidneys have failed can eat and drink whatever they like as long as they go to dialysis three times a week as scheduled. A) True B) False Answer: B 72) Alcohol increases urine output by inhibiting the release of ADH. A) True B) False Answer: A 73) The kidneys help regulate bloodpressure. A) True B) False Answer: A 74) Animals vary the composition of their urine depending on their environment and their need to conserve water. A) True B) False Answer: A SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 75) Urine is the watery liquid that contains substances filtered from the blood or the cells.

fluid that bathes all

Answer: interstitial 76) Ammonia, uric acid, and urea are products of the breakdown of digestion.

that accumulate because of protein

Answer: amino acids 77) The primary nitrogenous waste product excreted in the urine of all mammals is Answer: urea

78) The primary nitrogenous waste product of aquatic organisms is

Answer: ammonia 79) The funnel-shaped opening of a nephridium is known as a

Answer: nephrostome 80) The

is the region of the kidney involved in producing concentrated urine.

Answer: renalmedulla 81) Erythropoietin is released in response to low levels of

in the blood.

Answer: oxygen 82) What are the two main functions of the urinary system? Answer: Excretion of cellular wastes and maintenance of homeostasis by regulating water balance, pH, and ion concentration in body fluids 83) Explain the relationship between protein consumption and the nitrogenous waste products found in mammalian urine. Answer: Proteins are made up of amino acids, which contain an amino group. When more protein is consumed than can be used for making more protein, the amino group has to be removed in the liver from the amino acids. These amino groups are made into ammonia, which is extremely toxic. The liver immediately changes the ammonia into urea, which is less toxic. The kidneys filter the urea from the blood and excrete it inurine. 84) What are the four distinct anatomical components of the mammalian urinary system? Answer: Kidney, ureter, bladder, and urethra 85) Based on your knowledge of the differences between the male and female urinary systems, why are females at greater risk of bladder infections? Answer: The urethra is about five times longer in males than in females (8 inches compared with 1.5 inches). Therefore, the likelihood of bacteria entering the urethra and traveling to the bladder to cause infection is lower in males. 86) Name the two main parts of the nephron. Answer: Renal corpuscle (consisting of the glomerulus and glomerular capsule) and renal tubule 87) Because there is a high concentration of salt in the interstitial fluid around the nephron loop, what happens to the filtrate as it flows through the descending limb? Answer: Water moves out of the descending limb by osmosis into the interstitial fluid. 88) Where does the highest rate of reabsorption occur? Answer: In the proximal tubule 89) Explain why the process in the kidneys is called "filtration." (What is acting as a "filter"?) Answer: Blood pressure forces fluids from the blood through the walls of the porous glomerular capillaries into the glomerular capsule.

90) What is the functionof secretion? Answer: Substances that are harmful to the body, such as drugs, excess hydrogen ions, excess salt ions, and others, may be completely removed from the bloodstream by the tubules, which actively transport them into the filtrate. 91) Describe the process of hemodialysis. Answer: Blood flows through a semipermeable membrane suspended in dialyzing fluid, which allows wastes to diffuse into the fluid while retaining sugar, normal salt levels, and large particles. 92) How does drinking a lot of water affect ADH production and urine output? Answer: Increased water consumption causes a drop in the osmotic concentration of the blood. This inhibits ADH production, which increases urine output. 93) Briefly explain why animals that live in very dry climates have the longest nephron loops. Answer: The longer the nephron loop, the greater the concentrating ability of the kidney, thus facilitating the necessary excretion of waste without sacrificing essential water.

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 94) According to the illustration, blood entering which structure will undergo no further modification by the nephron?

A) Collecting duct B) Distal tubule C) Glomerular capsule D) Venule E) Glomerulus Answer: D

95) Based on this figure, what pathway is used during urinary catheterization, in which a tube is inserted into a patient to drain urine from the bladder?

A) From the left renal artery into the urinary bladder B) From the vena cava into the urinarybladder C) From the left ureter into the urinary bladder D) From the urethra into the urinary bladder Answer: D

96) Refer to the following diagram. Which of the following could result from localized brain damage to the pituitary gland?

A) Increased permeability of the collecting duct B) Extremely concentrated urine production C) Complete loss of urination D) Forming large amounts of diluteurine E) Water retention and bloating Answer: D 97) The likelihood of men over the age of 40 developing an enlarged prostate (often called benign prostatic hyperplasia, or BPH) increases with age. An enlarged prostate is not the same as cancer, and it does not increase a man's risk for developing prostate cancer. BPH is so common that it has been said that all men would have an enlarged prostate if they were to live long enough! Some of the complications of BPH are increased frequency of urination, reduced urine output, and uncontrolled "dribbling" after urination. After an enlarged prostate is surgically removed (a prostatectomy), these symptoms disappear. Based on this scenario and your knowledge of the urinary system, which of the following must be TRUE? A) Prostate enlargement reduces the ability of the kidneys to filter wastes from the bloodstream. B) The prostate is part of the kidney and assists in urine production. C) The prostate is the only gland that releases ADH, which decreases urine production. D) An enlarged prostate presses on the urethra and bladder, affecting urination. Answer: D

98) It is estimated that more than 90% of Americans get a daily dose of caffeine from coffee, sodas, tea, or "energy" drinks. Excessive caffeine intake can result in difficulty sleeping, jitteriness, and anxiety. It can also cause increased urination, which can lead to dehydration. Based on your knowledge of urinary systems and on the information provided in this scenario, which of the following explains the effects of caffeine? A) Caffeine increases the amount of erythropoietin in the blood. B) Caffeine decreases the amount of renin in the blood. C) Caffeine decreases the amount of ADH in the blood. D) Caffeine increases the amount of ADH in the blood. Answer: C 99) A friend receives the results of a urine test and finds that dissolved nutrients, such as amino acids and glucose, are present in his urine. You deduce that part of his kidney is not functioning properly. Which part is most likely malfunctioning? A) Proximal tubules B) Nephron loops C) Collecting ducts D) Renal pelvis E) Renal medulla Answer: A

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) All bacteria and virusesare A) causes of cancer. B) antibodies. C) microbes. D) pathogens. E) plasma cells. Answer: C 2) Which of the following is a harmless bacterium, in which mutated strains may cause toxic shock syndrome, inhabits your skin? A) Clostridium tetani B) Streptococcus pyogenes C) Staphylococcus aureus D) Aeromonas hydrophila E) Vibrio cholerae Answer: C 3) Which of the following immune system cells produce histamine? A) B cells B) Neutrophils C) T cells D) Mast cells E) Macrophages Answer: D 4) Cells that produce antibodies and provide future immunity against similar pathogens are A) natural killer cells. B) mast cells. C) T cells. D) dendritic cells. E) B cells. Answer: E 5)

are white blood cells that attack cancer cells. A) Microphages B) Natural killer cells C) Macrophages D) Neutrophils E) Mast cells Answer: B

6) Nonspecific internal defenses include A) skin. B) tears and saliva. C) T cells. D) inflammation. E) plasma cells. Answer: D

7) Which of the following is an example of a nonspecific response to infection? A) Formation of memory B cells B) Fever C) Activation of T cells D) Production of antibodies Answer: B 8) Which of the following predictions is the most accurate about a person who has normal external barriers and specific internal defenses but lacks nonspecific internal defenses? A) Invading microbes will be able to enter through the respiratory tract. B) He will have many more infections than normal. C) He won't get sick because the specific defenses will kill invading pathogens. D) He won't get sick because the external barriers will keep out pathogens. Answer: B 9) The skin inhibits bacterial growth by releasing A) lysozyme. B) T cells. C) macrophages. D) lactic acid. E) white bloodcells. Answer: D 10) "Big eater" cells that ingest and destroy microbes are A) plasma cells. B) macrophages. C) mast cells. D) T cells. E) natural killer cells. Answer: B 11) Which of the following is NOT part of the body's first line of defense against microbial attack? A) Lysozyme B) Stomach acid C) Skin D) Phagocytes E) Mucus Answer: D 12) How does the skin act as a barrier to microbial invasion? A) Dead skin cells are packed with keratin, an antibacterial protein that punches holes in bacterial membranes. B) Sweat and sebaceous gland secretions inhibit bacterial growth. C) Dendritic cells patrol the skin's surface, producing secretions that inhibit microbe growth. D) It releases B cells and T cells to fight infections. Answer: B

13) These white blood cells kill virus-infected cells exhibiting "non-self" major histocompatibility complex (MHC) proteins. A) Macrophages B) Plasma cells C) Natural killer cells D) Neutrophils E) Dendritic cells Answer: C 14) Inflammation occurs in response to chemicals, such as histamine, secreted by A) plasma cells. B) T cells. C) mast cells. D) neutrophils. E) natural killer cells. Answer: C 15) Which of the following defense cells are able to squeeze through the intact walls of capillaries into the tissues to attack and ingest invading microbes? A) Lymphocytes B) Mast cells C) B cells D) Natural killer cells E) Phagocytes Answer: E 16) How does histamine contribute to the inflammatory response? A) It increases warmth at the site of infection. B) It makes capillaries less leaky. C) It attracts macrophages to the site of infection. D) It decreases blood flow to the injured area. E) It causes fever. Answer: A 17) Pyrogens are produced by phagocytic white blood cells in response to infection. Pyrogens A) are the chemicals that triggers an inflammatory response. B) increase the concentration of iron in the blood. C) relax the smooth muscle of arterioles delivering blood to the site of infection. D) kill bacteria by digesting their cell walls. E) initiate an increase in body temperature. Answer: E 18) Natural killer cells prevent viral infection by A) ingesting the viruses and digestingthem. B) secreting proteins that punch holes in viral plasma membranes. C) phagocytizing cells that are infected with a virus. D) enzymatically destroying virus-infected cells. Answer: D

19) Which of the following is a consequence of histamine release? A) Constriction of the smooth muscle that surrounds arterioles B) Leaky capillary walls C) Decreased blood flow D) Initiation of blood clotting Answer: B 20) Aspirin reduces fevers; however, many physicians do NOT recommend aspirin to patients with a low-grade fever. Why not? A) Fevers reduce bacterial reproduction rates. B) Aspirin increases the release ofpyrogens. C) Fevers decrease the amount of interferon produced by the body. D) Aspirin increases the activity of phagocytic white blood cells. Answer: A 21) Macrophages A) release chemicals that initiate bloodclotting. B) cannot squeeze through capillary walls. C) produce proteins that digest bacterial cell walls. D) are large, ciliated cells found in tears, saliva, and mucus. E) phagocytize invading microbes Answer: E 22) Natural killer cells A) engulf and destroy invading bacteria. B) produce secretions that inhibit the growth of pathogenic microbes. C) destroy body cells that have been invaded by viruses. D) are located on the surface of the skin. E) are a type of lymphocyte. Answer: C 23) Which of the following is NOT part of the inflammatory response? A) The release of histamine B) Localized tissue swelling C) Migration of phagocytes to the site of injury D) The release of antibodies E) Elevated body temperature Answer: D 24) Why is it sometimes a disadvantage to take aspirin to reduce a fever? A) Aspirin reduces the fever and therefore decreases the activity of phagocytic white blood cells. B) Aspirin reduces the production of toxins so that you feel better, even though you are still sick and need to rest. C) Aspirin reduces the fever and stimulates a dangerous inflammatory response. D) Aspirin makes you irritable and fatigued. Answer: A

25)

are substances that induce fever. A) MHC proteins B) Pyrogens C) Cytokines D) Interferons Answer: B

26) Fever is caused by A) the effect of pyrogens on the hypothalamus. B) decreased white blood cell count in the bloodstream. C) increased blood flow to the brain. D) the release of histamine by damaged cells. Answer: A 27) Interferon A) kills bacteria. B) causes fever. C) causes inflammation. D) helps cells resist viral infection. Answer: D 28) Most specialized immune cells are located in the A) hypothalamus. B) gall bladder. C) lymph nodes. D) thyroid gland. Answer: C 29) Which of these are immune cells produced by the bone marrow? A) Red blood cells B) B cells C) T cells D) Both B and T cells E) B cells, T cells, and red blood cells Answer: D 30)

cells are immune system cells that mature in the bone marrow. A) Memory B) Cytotoxic T C) Helper T D) B Answer: D

31) Foreign proteins that bind to an antibody are called A) cytotoxins. B) histamines. C) antigens. D) interferons. Answer: C

32) MHC proteins A) control antibody gene expression. B) cause cancer. C) are released by T cells during an infection to kill virus-infected cells. D) help white blood cells distinguish "self" from "non-self." Answer: D 33) Antibodies are A) amino acidmolecules. B) derived from vitamins. C) carbohydrate molecules. D) produced by T cells. E) protein molecules. Answer: E 34) Where on the Y-shaped antibody does an antigen bind? A) Stem of the Y B) Constant region of thelight chain C) Tip of the arm D) Constant region of the heavy chain Answer: C 35) Which of the following antibody types is the most common in the blood, lymph, and interstitial fluid? A) IgE B) IgM C) IgD D) IgA E) IgG Answer: E 36) The proteins that must be matched as closely as possible between an organ donor and a recipient are the proteins. A) MHC B) cytokine C) antibody D) clotting factor Answer: A 37) What are antibodies? A) Viruses B) Proteins produced by B cells that bind to foreign proteins C) Cells that undergo apoptosis D) Bacteria E) Proteins produced by T cells that bind to foreign proteins Answer: B

38) Antibodies are attached to the surface of a B cell by A) the stem of the antibody. B) the heavy chain of the arm of the antibody. C) mucus. D) the light chain of the arm of the antibody. E) sticky proteins produced by T cells. Answer: A 39) The constant region of anantibody A) recognizes and binds to theantigen. B) has no function. C) determines where the antibody is located and its role in the immune response. D) stimulates the production of macrophages and T-cells. Answer: C 40) Antibodies are most similar in structure to A) B-cell receptors. B) T-cell receptors. C) bacteria. D) macrophages. E) viruses. Answer: B 41) Clonal selection occurs when A) antibodies that are the most common become cloned. B) daughter cells differentiate into memory B cells and plasma cells. C) scientists clone antibodies for specific diseases and use them to prepare vaccines. D) natural selection favors specific white blood cells and they multiply rapidly. E) antigen-antibody binding causes selected B cells to multiply. Answer: E 42) Which of the following provides cell-mediated immunity? A) Red blood cells B) Antibodies C) T cells D) B cells Answer: C 43) Which type of cell secretes antibodies into the blood? A) Memory B) Helper T C) Plasma D) Cytotoxic T Answer: C 44) Individual B cells produce A) an infinite diversity of antibodies. B) several different types of antibodies. C) their own unique antibody. D) the antibodies specified by its constant region gene. Answer: C 7

45) Some of the daughter cells resulting from clonal selection of a B cell differentiate into plasma cells. Which of these is a function of plasma cells? A) They produce specific antibodies and release them into the blood. B) They act as natural killer cells and destroy cancercells. C) They are responsible for cell-mediatedimmunity. D) They transform into helper T cells and bind to antigens displayed by a dendritic cell. Answer: A 46) Complement is a collection of A) phagocytic cells that consume virus-infected body cells. B) nonspecific antigens. C) antibiotics. D) antibodies. E) blood proteins that assist antibodies. Answer: E 47) The primary function of cell-mediated immunity is to A) promote the production of antibodies. B) decrease the amount of complement. C) protect the body against extracellularparasites. D) destroy cancerous or virus-infected hostcells. E) increase the number of macrophages. Answer: D 48) How does a cell "inform" the immune system that it is infected with a virus? A) It synthesizes enzymes that activate helper T cells. B) It releases histamine into the bloodstream. C) It produces interferon. D) It displays viral proteins on its membrane. E) It secretes steroid hormones. Answer: D 49) Your immune system has identified some body cells infected with an influenza (flu) virus. Which of the following will the immune system use to destroy these infected cells? A) Antigens B) B cells C) Phagocytes D) Antibodies E) Cytotoxic T cells Answer: E 50) Plasma cells are derived from A) macrophages. B) dendritic cells. C) neutrophils. D) B cells. E) T cells. Answer: D

51) Last summer a bee stung you for the first time. You developed only a small area of redness and swelling at the site. However, if you are stung again and have a severe reaction that occurs more rapidly, you know that this is due to the activation of A) tissue macrophages. B) memory cells. C) helper T cells. D) complement. E) cytotoxic T cells. Answer: B 52) You were sick with the flu last winter. Why then does your doctor suggest you be vaccinated against the flu this year? A) The virus inactivates helper Tcells. B) Surviving the flu one year inhibits the immune system the second year. C) Flu viruses mutate rapidly. D) The virus blocked your immune system's ability to produce memory cells. Answer: C 53) Vaccinations are effective because they stimulate the production of A) cytotoxic T B) plasma C) memory D) helper T

cells.

Answer: C 54) Antibiotics are NOT effective against A) bacteria. B) viruses. C) protists. D) fungi. Answer: B 55) The recent appearance of antibiotic-resistant strains of bacteria is an example of A) evolution by natural selection. B) natural immunity. C) inflammation. D) the action of memory cells. Answer: A 56) Triclosan is a common antibiotic used in antiperspirants, toothpastes, and antibacterial soaps. You are a doctor studying the evolution of bacterial resistance to triclosan. You need to find a population of nonresistant bacteria. Where should you look? A) In areas with low percentages of bacterial infection B) In areas where triclosan-containing products are used frequently C) In areas where bacteria are usually not found D) In areas where these triclosan-containing products have not been used Answer: D

57) Vaccinations involve injecting into the person or animal. A) antibodies against similar diseases B) antibodies against the disease C) antibiotics D) the disease itself E) weakened or killedmicrobes Answer: E 58) Vaccinations protect against future exposure to disease organisms by A) increasing the number of red blood cells. B) forming memory cells. C) increasing complement proteins. D) stimulating suppressor T cells. Answer: B 59) Who first performed vaccinations by inoculating children with cowpox virus to provide immunity against smallpox? A) Edward Jenner B) Milkmaids C) Lady Montague D) Louis Pasteur Answer: A 60) Why are new flu shots necessary every year? A) Flu viruses have a high mutation rate. B) Depending on the year, either bacteria or viruses cause the flu. C) The antiviral chemicals in flu shots last only 11 months. D) Flu shots do not result in the production of memory cells. Answer: A 61) Allergies occur when A) too much complement is released into the blood. B) foreign MHC proteins trigger an immune response. C) antibodies malfunction and attack "self" cells. D) mast cells release histamine in response to harmless substances. Answer: D 62) An autoimmune disease is characterized by A) an insufficient or completely inactivated immune system. B) the absence of an inflammatoryresponse. C) "anti-self" antibodies that can destroy some "self" cells. D) increased lysozyme enzyme concentration in saliva, tears, and mucous secretions. Answer: C 63) HIV selectively destroys A) memory B cells. B) helper T cells. C) plasma cells. D) cytotoxic T cells. E) all B and T cells. Answer: B 10

64) When AIDS patients die, it is because A) they lack HIV antibodies. B) HIV destroys the internal organs. C) their immune systems cannot defend them from other infections. D) the AIDS virus has a high rate of mutation. E) there are no treatments to slow the progress of the disease. Answer: C 65) Would you expect someone with AIDS to have inflammation and/or a fever in response to an infection? A) No, because HIV weakens or destroys the nonspecific defenses. B) No, because HIV weakens or destroys the specific immune response. C) Yes, because HIV does not affect the specific immune response. D) Yes, because HIV does not destroy the nonspecific defenses. Answer: D 66) Chemotherapy drugs make patients nauseous because they A) attack rapidly dividing cells, including those lining the digestive tract. B) stimulate stomach acid production. C) cause fever, which can triggernausea. D) interfere with the brain's interpretation of sensory input. Answer: A 67) Cancer cells form in our bodies every day. How does the immune system destroy them? A) Antibodies attach to the cancer cells and then macrophages engulf them. B) Immune secretions, such as interferon, disrupt the DNA of the cancer cells. C) The immune system cannot destroy cancer cells. D) Fevers slow the replication of cancerous cells. E) Natural killer and cytotoxic T cells recognize the cancer cells as foreign and attack them. Answer: E 68) Vertebrate and invertebrate immune systems are similar in that their first line of defense is a nonspecific external barrier; however, they differ in that invertebrates do not produce white blood cells. A) True B) False Answer: B 69) Pus, a thick white substance that sometimes accumulates at the site of an infection, is a mixture of dead bacteria, debris, and white blood cells. A) True B) False Answer: A 70) It is likely that a hospitalized patient with a high lymphocyte count has some type of infection. A) True B) False Answer: A 71) Antibodies are nonspecific. A) True B) False Answer: B 11

72) All B cells produce the same type of antibodies. A) True B) False Answer: B 73) IgD, IgM, IgG, IgA, and IgE are types of white blood cells. A) True B) False Answer: B 74) Antibodies and T-cell receptors are both produced by B cells. A) True B) False Answer: B 75) B cells and T cells cannot design and build antibodies or T-cell receptors to fit specific invading antigens. A) True B) False Answer: A 76) The rejection of a transplanted kidney is due to a humoral immune response. A) True B) False Answer: B 77) Type 1 diabetes is considered an autoimmune disease because the body's immune system attacks and destroys insulin-producing cells in the pancreas. A) True B) False Answer: A 78) HIV weakens a person's ability to fight off other infections by infecting and destroying helper T cells. A) True B) False Answer: A 79) HIV may be transmitted from one individual to another by holding hands. A) True B) False Answer: B 80) Viruses are known to cause certain cancers. A) True B) False Answer: A 81) Cancer is the leading cause of death in the United States. A) True B) False Answer: B 12

SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 82) As part of the defense system of the body, the skin produces sweat, which contains natural antibiotics that inhibit the growth of bacteria and fungi. Answer: nonspecific (or innate) 83) Phagocytes patrol the body's tissues and ingest invading microbes. Phagocytic cells include macrophages, dendritic cells, and . Answer: neutrophils 84) In the body, infections are often associated with and white blood cells

, a whitish mixture of dead bacteria, damaged tissue,

Answer: pus 85) B cells mature in the bone marrow, whereas T cells migrate to the they mature.

gland early in embryonic life, where

Answer: thymus 86)

immunity deals with microbes circulating in your bloodstream, whereas with microbes hiding within bodycells.

immunity deals

Answer: Humoral; cell-mediated 87) HIV stands for human

virus.

Answer: immunodeficiency 88) List the human body's three lines of defense against disease. Answer: Nonspecific external barriers (e.g., skin and mucous membranes), nonspecific internal defenses (e.g., phagocytic cells), and specific (adaptive) internal defenses 89) How does the extra mucus in a runny nose protect against microbial infection? Answer: Airborne microbes are trapped in the mucus, which can then drip out of the nose or be swept into the pharynx by cilia and swallowed. Additionally, bacteria are killed by lysozymes in the mucus. 90) What mechanisms do natural killer cells use to destroy body cells that have been infected by cancer or a virus? Answer: They open up large holes in the membrane of the infected cells, destroying the cells. In addition, they secrete enzymes that break down the cell membranes. 91) Why do inflamed tissues appear red, swollen, and warm? Answer: Affected cells release histamine, which makes capillaries leaky and dilates arterioles, causing increased blood flow. This causes redness (from increased blood flow), warmth, and swelling. 92) Briefly describe how a fever develops in response to infection. Answer: Certain types of bacteria and phagocytic white blood cells release pyrogens, which trigger the hypothalamus to raise its set point. Behaviors, such as shivering, and physiological changes, such as increases in fat metabolism, cause the rise in body temperature. 93) What three steps do all adaptive immune responses include? Answer: (1) Lymphocytes recognize the invading microbe; (2) they attack the invading microbe; and (3) they retain memory of the invader to prevent future infection by the same microbe.

94) Why doesn't your immune system attack your own cells? Answer: Immature lymphocytes that respond to "self" antigens (self MHCs) are destroyed before they reach maturity. Any self-reactive lymphocytes that escape apoptosis are prevented from attacking self body cells by regulatory T cells. 95) What are the functions of helper T cells? Answer: They stimulate production and differentiation of both cytotoxic T and B cells, and the formation of memory T cells. 96) List the events that occur in an allergic reaction. Answer: (1) Allergen binds to antibodies on specific B cells; (2) activated B cells stimulated to proliferate producing plasma cells; (3) plasma cells produce antibodies against the allergen, which bind to mast cells; (4) allergen-binding to mast cell antibodies stimulates release of histamine, which increases capillary permeability (all of which cause allergic symptoms). 97) Briefly explain why children born with severe combined immune deficiency (SCID) often do not experience infection for several months after birth. Answer: Antibodies from the mother during pregnancy or breast-feeding provide temporary immunity. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 98) This figure illustrates the structure of an antibody. Which part of the antibody binds to the antigen?

A) Region A B) Region B C) Both regions A and B can bind to the antigen. Answer: A

99) Based on this figure, when does the maximum immune response occur?

A) Between 1 and 2 weeks after the secondexposure B) 1 week after the thirdexposure C) Between 2 and 3 weeks after the first exposure D) Within 1 week of the second exposure E) 1 week after the first exposure Answer: A

100) As shown in this figure, upon re-exposure to pollen, the pollen binds to

A) T cells. B) plasma cells. C) free antibodies within the capillaries. D) histamine. E) antibodies on mast cells. Answer: E

101) A student athlete suffered an injury while playing softball and subsequently has pain in her shoulder. Her doctor prescribes cortisone, a strong anti-inflammatory steroid. When filling the prescription, the pharmacist warns her that an increased risk of contracting a bacterial infection, such as pneumonia, is associated with the use of steroids. Based on your knowledge of the immune system and on the information in this scenario, what do you conclude about anti-inflammatory steroids? A) They stimulate bacterial reproduction. B) They cause a temporary condition similar to an autoimmune disease. C) They inhibit a part of the nonspecific immune response. D) They interfere with mast cell function. Answer: C 102) As a doctor, you discover a new virus that prevents the body from creating memory cells. Based on what you know about human defenses against disease, you predict that this virus is infecting and destroying which type of white blood cell? A) Dendritic cells B) Macrophages C) Mast cells D) Natural killer cells E) Lymphocytes Answer: E 103) You are a forensic biologist and have been asked to review the files of an old, unsolved murder case. The autopsy report is missing a lot of important information, but you read that the victim had a thymus gland that was just starting to shrink. Based on this information alone, what can you conclude about the victim? A) He was between 1 and 6 years old. B) He was between 12 and 16 years old. C) His lymphatic system was infected and being destroyed by an unknown virus. D) He died of natural causes, most likely an autoimmune disease. Answer: B 104) When Europeans first came to North America, one of the most disastrous impacts on native populations was the introduction of "Old World diseases." These diseases, such as smallpox, influenza, and plague, devastated the Native American population as the number of settlers grew steadily. One author has called this "the greatest human catastrophe in history, far exceeding . . . the Black Death of Medieval Europe." Based on this scenario and what you know about the immune system, what can you conclude about the Native American and European populations? A) Native Americans were genetically vulnerable to these diseases, which are not caused by microbes. B) Native American immune systems had not evolved in the presence of these novel microbes and were at a great disadvantage when exposed to them over a relatively short period of time. C) Native American immune systems were inherently inferior to those of the Europeans and were not capable of developing immunity to the same microbes. D) The Europeans had been vaccinated against all of these diseases. Answer: B

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Endocrine communication depends on A) chemicals secreted through ducts. B) cytoplasmic movement through gap junctions. C) chemicals secreted into the blood for delivery. D) target cells not binding to a hormone. E) electrical signals within individual cells. Answer: C 2) Local hormones are A) released by a cell into the surrounding interstitial fluid and affect only other nearby cells. B) released from one cell and transferred via the blood to target cells throughout the body. C) released from gap junctions directly into the cytoplasm of the connected cell. D) electrical signals that move between adjacent cells. E) released from a nerve cell and then diffuse across a synaptic gap to influence the target cells. Answer: A 3) Which of the following proteins are required for target cells to interact with hormones? A) Receptors B) Cyclic adenosine monophosphates (AMPs) C) Neurotransmitters D) Neuromodulators E) Response proteins Answer: A 4) Endocrine hormones are A) released from a nerve cell and diffuse across a synaptic gap to influence the target cells. B) chemicals released from certain cells that travel via the blood to target cells. C) released from gap junctions directly into the cytoplasm of the connected cell. D) electrical signals that move between adjacent cells. E) chemicals released by cells into the surrounding extracellular fluid and affect only other nearby cells. Answer: B 5) Neurotransmitters are A) chemicals released by cells into the surrounding extracellular fluid and affect only other nearby cells. B) chemicals released from certain cells that travel via the blood to target cells. C) electrical signals that move between adjacent cells. D) released from gap junctions directly into the cytoplasm of the connected cell. E) released from a nerve cell and diffuse across a synaptic gap to influence the target cells. Answer: E 6) Which of the following causes cervical dilation and helps stimulate uterine contractions during labor? A) Oxytocin B) Acetylcholine C) Prostaglandins D) Progesterone E) Estrogen Answer: C

7) Histamine is an example ofa(n) A) prostaglandin. B) endocrine hormone. C) synaptic messenger. D) neurotransmitter. E) local hormone. Answer: E 8) What are prostaglandins? A) Modified amino acids B) Steroids C) Modified fatty acids D) Carbohydrates E) Peptides or proteins Answer: C 9) You woke up this morning with a headache from staying up cramming last night, so you took an aspirin. This should A) help because aspirin increases neurotransmitter levels. B) help because aspirin inhibits prostaglandin synthesis. C) help because aspirin stimulates the production of prostaglandins. D) make the headache worse because aspirin increases the production of endorphins. E) help because aspirin blocks the production of endorphins. Answer: B 10) Testosterone is made in the testes, where it stimulates sperm development. Additionally, testosterone is carried in the blood throughout the body, stimulating the growth of facial hair and muscles. Therefore, testosterone is A) a local hormone. B) a neurotransmitter. C) an endocrine hormone. D) both a local and an endocrine hormone. E) both a neurotransmitter and an endocrine hormone. Answer: D 11) Which of these are made at sites of tissue damage, where they cause inflammation and pain as part of the healing process? A) Prostaglandins B) Neurotransmitters C) Nitric oxide D) Gap junctions E) Protein receptors Answer: A 12) Endocrine glands secrete their products A) into a gap junction. B) directly into target cells. C) into interstitial fluid. D) into ducts that open into a body cavity. E) into a synapse. Answer: C

13) During childbirth, the hormone oxytocin stimulates the smooth muscles of the uterus to contract; however, smooth muscles lining the digestive tract are not affected by oxytocin. Which statement correctly explains this scenario? A) Smooth muscles of the digestive tract do not contain receptors for oxytocin. B) Endocrine hormones such as oxytocin do not travel through the blood, so they do not make contact with digestive tract muscles. C) Oxytocin is released by the fetus and diffuses into the amniotic fluid inside the uterus. Therefore, only uterine muscles are stimulated. D) Oxytocin is a local hormone released by the uterus, so other muscles do not receive its signals. E) The digestive tract muscles of the mother's body are temporarily paralyzed by the anti-pain medications administered during labor. Answer: A 14) Peptide hormones, amino acid-derived hormones, and steroid hormones are types of A) local hormones. B) endocrine hormones. C) neurotransmitters. D) paracrine hormones. E) hormone receptors. Answer: B 15) How do endocrine hormones affect their target cells? A) They cause changes in cell metabolism only. B) They increase the permeability of the target cell. C) They affect gene transcription only. D) They stimulate the synthesis of glycogen. E) They cause changes in cell metabolism and/or gene transcription. Answer: E 16) Because steroid hormones are lipid soluble, they A) dissolve easily in water. B) are repelled by the plasma membrane. C) only affect muscle cells with high lipid content. D) must bind to receptor proteins on the surface of the plasma membrane. E) can pass through the plasma membrane. Answer: E 17) The antidiuretic hormone (ADH) is regulated by negative feedback. Which of the following statements is correct about ADH regulation? A) Drinking a lot of water will increase the rate of ADH production. B) A high blood concentration of ADH will increase the rate of ADH production. C) A high blood concentration of ADH will make you feel thirsty. D) Loss of water from your bloodstream will limit further production of ADH. E) A high blood concentration of ADH will cause you to excrete dilute urine. Answer: D

18) A diet that lacks cholesterol would limit the production of A) amino acid derivatives. B) cyclic AMP. C) peptide hormones. D) acetylcholine. E) steroid hormones. Answer: E 19) Water-soluble hormones bind to receptors located A) on the mitochondria B) on DNA C) in the nucleus D) on the plasma membrane E) in the cytoplasm

of the target cell.

Answer: D 20) When the hormone epinephrine binds to receptors on the surface of a heart muscle cell, a new molecule, called cyclic AMP, is produced. Cyclic AMP then causes the heart muscle cells to contract more strongly, increasing blood flow throughout the body. In this example, cyclic AMP is acting as a(n) A) second messenger. B) intercellular enzyme. C) energy carrier. D) target cell. E) hormone. Answer: A 21) Most steroid hormones are synthesizedfrom A) insulin. B) amino acids. C) cholesterol. D) linoleic acid. E) glucose. Answer: C 22) Steroid hormones can diffuse into all cells of the body; however, not all cells respond to steroid hormones. Why? A) Only cells with surface protein receptors can respond to steroid hormones. B) Only cells displaying plasma membrane receptors can respond to a lipid-soluble hormone. C) Not all cells contain the genes necessary to respond to steroid hormones. D) Only cells containing cytoplasmic or nuclear receptors to the steroid hormone can respond. E) Not all cells are lipid soluble and therefore they cannot respond to steroid hormones. Answer: D 23) ADH increases fluid retention when the body sweats and decreases fluid retention when someone has consumed large amounts of water. This is an example of A) positive feedback. B) negative feedback. C) neurotransmitter activity. D) paracrine communication. E) synaptic communication. Answer: B

24) When you scratch a mosquito bite, you damage some cells. Damaged cells release histamine, which causes localized swelling that can crush additional cells, causing the release of more histamine. This is an example of A) positive feedback. B) negative feedback. C) neurotransmitter activity. D) paracrine communication. E) synaptic communication. Answer: A 25) When you eat a bag of cookies, your blood sugar level increases. As blood sugar levels rise, insulin levels increase to move the sugar into the cells and lower the blood sugar level. As the blood sugar level drops, so does the level of insulin. This is an example of A) positive feedback. B) negative feedback. C) neurotransmitter activity. D) paracrine communication. E) synaptic communication. Answer: B 26) The pituitary releases hormones produced by cells in the hypothalamus. A) median B) anterior C) ventral D) posterior E) dorsal Answer: D 27) Which of these hormones does the posterior pituitary release? A) Adrenocorticotropic hormone (ACTH) B) Gonadotropins C) Growth hormone D) ADH E) Cortisol Answer: D 28) Most of the normal variation in human height is due to the influence of A) ADH. B) thyroxine. C) testosterone. D) growth hormone. E) epinephrine and norepinephrine. Answer: D 29) All releasing hormones produced by neurosecretory cells of the hypothalamus are A) modified fatty acids. B) ions. C) steroids. D) peptides. E) modified amino acids. Answer: D

30) Oxytocin and ADH are produced by the neurosecretory cells of the hypothalamus; however, they are stored in and released from the A) thyroid. B) parathyroid. C) posterior pituitary. D) adrenal medulla. E) pancreas. Answer: C 31) A common occurrence for nursing mothers is "milk let-down," which stimulates the mother's mammary glands to eject milk. Which hormone is responsible for the milk letdown reflex? A) Prolactin B) Follicle-stimulating hormone (FSH) C) Estrogen D) Oxytocin E) Progesterone Answer: D 32) Sometimes when a new mother is nursing her baby, she experiences abdominal cramping. Which hormone is responsible? A) Prolactin B) Estrogen C) Progesterone D) Oxytocin E) FSH Answer: D 33) Which of the following glands produces hormones that regulate the secretory activity of other endocrine glands? A) Pancreas B) Anterior pituitary C) Ovaries and testes D) Adrenal cortex E) Thyroid Answer: B 34) Thymosin is a hormone produced by the thymus gland. If production of thymosin is inhibited, then A) T cells do not develop. B) progesterone production stops. C) blood glucose levels fluctuate wildly. D) dehydration occurs. E) bone density decreases. Answer: A 35) Hypothalamic hormones that stimulate the production of anterior pituitary hormones are called A) ACTH. B) thyroid-stimulating hormones (TSHs). C) releasing hormones. D) secondary messengers. E) inhibiting hormones. Answer: C

36) You arrive at the beach only to discover that you forgot your water bottle. You decide to tough it out. However, after spending 4 hours in the sun you decide to head home. If you were to take a blood sample now, you would expect to find elevated levels of A) FSH. B) ADH. C) insulin. D) TSH. E) ACTH. Answer: B 37) Dwarfism is sometimes due to inadequate levels of a hormone produced by which gland? A) Parathyroid B) Adrenal cortex C) Anterior pituitary D) Adrenal medulla E) Pancreas Answer: C 38) If basal metabolism drops, which anterior pituitary hormone is released to stimulate the thyroid gland to produce thyroxine? A) Prolactin B) ACTH C) FSH D) ADH E) TSH Answer: E 39) Children who are pituitary dwarfs can now grow to normal height because of A) pituitary transplants. B) large supplies of growth hormone from dead animals. C) genetic repair before birth. D) genetically engineered production of growth hormone by bacteria. E) the invention of synthetic growth hormone. Answer: D 40) After hiking for an hour in the desert without drinking water, your circulating levels of ADH will be A) below average. B) above average. C) average. Answer: B 41) What is the effect of increased levels of parathyroid hormone? A) Increased metabolism B) Increased estrogen levels C) Decreased metabolism D) Increased blood calcium levels E) Decreased blood calcium levels Answer: D

42) Iodized salt provides the essential nutrient iodine. Iodine is important in preventing A) menstrual cramps. B) high blood pressure. C) gigantism. D) diabetes. E) a goiter. Answer: E 43) Inadequate levels of thyroxine during infancy results in retardation of mental and physical growth. This syndrome is known as A) acromegaly. B) diabetes. C) beriberi. D) goiter. E) cretinism. Answer: E 44) Due to negative feedback mechanisms, high levels of thyroxine in the blood decrease the A) metabolic rate. B) rate of cell division. C) growth rate. D) release of TSH. E) rate of insulin production. Answer: D 45) Islet cells in the pancreas produce which hormone(s)? A) They produce glucagon only. B) Islet cells do not producehormones. C) Each cell produces either glucagon or insulin. D) They produce insulin only. E) Each cell produces both glucagon and insulin. Answer: C 46) Insulin blood glucose, whereas glucagon A) increases; decreases B) decreases; increases C) does not affect; controls D) controls; does not affect E) makes; destroys

blood glucose.

Answer: B 47) Which pair of hormones is responsible for maintaining relatively constant blood glucose levels? A) Aldosterone and insulin B) Calcitonin and TSH C) ADH and growth hormone D) Insulin and glucagon E) Thyroxine and thymosin Answer: D

48) Which of the following triggers the release of calcium from bones? A) Calcitonin B) Insulin C) Prolactin D) Parathyroid hormone E) Oxytocin Answer: D 49) Which hormone lowers blood glucose levels? A) Insulin B) Glucagon C) Estrogen D) Growth hormone E) Cortisol Answer: A 50) Diabetes mellitus is due to an inability to produce or respond to which hormone? A) Insulin B) Glucagon C) Thyroxine D) ADH E) Glucocorticoids Answer: A 51) If you eat a meal that is high in sugar, which hormone will stimulate your cells to remove the sugar from your blood? A) Glucagon B) Glucocorticoids C) Thyroxine D) Glycogen E) Insulin Answer: E 52) Several hours after a meal, glucagon increases blood glucose levels by activating an enzyme that breaks down glycogen, which is stored primarily in the A) small intestine. B) pancreas. C) liver. D) kidneys. E) heart. Answer: C 53) Which hormone prepares the uterus to receive and nourish a fertilized egg? A) FSH B) Oxytocin C) Progesterone D) Luteinizing hormone (LH) E) Insulin Answer: C

54) Which of the following best explains why anabolic steroid abuse by male athletes can lead to a decrease in testes size? A) Circulating anabolic steroids decrease the release of FSH and LH, which slow down growth and function of the testes. B) High levels of anabolic steroids cause the adrenal glands to release more estrogen. C) High levels of anabolic steroids increase the production of testosterone through positive feedback, which decreases the size of thetestes. D) Circulating anabolic steroids increase the release of FSH and LH, which slow down growth and function of the testes. E) High levels of anabolic steroids decrease the production of testosterone through negative feedback, which decreases the size of thetestes. Answer: E 55) Aldosterone release is stimulated by A) increased blood glucose concentrations. B) decreased levels of blood sodium. C) increased levels of blood sodium. D) increased levels of growth hormone. E) decreased blood glucose concentrations. Answer: B 56) The adrenal medulla produces hormones in response to A) signals from the posterior pituitary. B) reduced blood levels ofthyroxine. C) stress or exercise. D) light. E) signals from the anterior pituitary. Answer: C 57) Which of the following hormones suppresses the immune response? A) LH B) Cortisol C) FSH D) ACTH Answer: B 58) Thymosin, produced by the thymus, stimulates the maturation of A) all white blood cells. B) B cells. C) T cells. D) red blood cells. E) both T and B cells. Answer: C 59) Which of the following is a hormone that is released by fat cells? A) Oxytocin B) Leptin C) Prolactin D) Glucagon E) Epinephrine Answer: B

60) The thymus produces called T cells. A) thyroxine B) testosterone C) ACTH D) insulin E) thymosin

, a hormone that stimulates the maturation of specialized white blood cells

Answer: E 61) Which gland responds to light and is involved in daily rhythms in some animals? A) Pineal B) Adrenal C) Thymus D) Pituitary E) Pancreas Answer: A 62) Decreased levels of ADH cause A) increased metabolism. B) dehydration. C) hunger. D) fever. E) water weight gain. Answer: B 63) Taking this exam might have caused your adrenal cortex to produce cortisol, the most common glucocorticoid. Cortisol is usually produced in response to A) a drop in blood pressure. B) stress or anxiety. C) increased brain activity. D) the release of adrenaline. E) inactivity. Answer: B 64) Histamine is a local hormone. A) True B) False Answer: A 65) Contractions of the uterus during childbirth are stimulated by oxytocin. A) True B) False Answer: A 66) In paracrine communication, paracrine glands secrete their products directly into the bloodstream. A) True B) False Answer: B

67) Only mammals produce hormones. A) True B) False Answer: B 68) Steroid hormones are lipid soluble and diffuse through the plasma membrane into a cell. A) True B) False Answer: A 69) Peptide hormones such as insulin cannot pass through the plasma membrane so they bind to receptors on the target cell's surface, triggering the production of second messengers. A) True B) False Answer: A 70) A second messenger, such as cyclic AMP, carries a hormonal signal to molecules inside a cell. A) True B) False Answer: A 71) Thyroxine is an amino acid-derived hormone that binds to plasma membrane receptors on the surface of target cells. A) True B) False Answer: B 72) Positive feedback mechanisms enhance changes in the body. A) True B) False Answer: A 73) Insulin production is regulated by a positive feedback loop that helps maintain healthy blood sugar levels. A) True B) False Answer: B 74) Only males make the hormonetestosterone. A) True B) False Answer: B 75) Overproduction of thyroxine causes a decrease in metabolic rate and energy levels. A) True B) False Answer: B

76) Low blood oxygen levels trigger the release of erythropoietin. A) True B) False Answer: A 77) As TSH levels increase, thyroxine levels should decrease. A) True B) False Answer: B 78) Neurosecretory cells connect the hypothalamus directly to the posterior pituitary. A) True B) False Answer: A 79) Increased levels of stress and trauma may enhance the release of cortisol. A) True B) False Answer: A 80) Alcohol prevents dehydration by increasing the production of ADH. A) True B) False Answer: B 81) Blood glucose levels are regulated by glucagon and insulin, two hormones produced by the pituitary gland. A) True B) False Answer: B 82) Mineralocorticoids from the adrenal gland, such as aldosterone, regulate salt metabolism. A) True B) False Answer: A 83) The adrenal medulla secretes epinephrine in response to stress or exercise. A) True B) False Answer: A SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 84) Endocrine communication involves hormones that reach their target cells via the bloodstream, whereas communication involves local hormones that affect nearby cells. Answer: paracrine 85)

are an important group of local hormones that produce a variety of effects, including uterine contractions, inflammation, pain sensations, and cervical dilation. Answer: Prostaglandins

86) The three classes of vertebrate endocrine hormones are

, and

Answer: peptides (or proteins); amino acid derivatives; steroids 87) Steroid hormones aresynthesized from

Answer: cholesterol 88) Nitric oxide gasis a because it initiates a chain of biochemical reactions within a target cell in response to the binding of a hormone to a plasma membrane receptor. Answer: second messenger 89) When a blood vessel is damaged, platelets adhere to the damaged site and release chemicals, which attract additional platelets. Thus, platelet attraction is considered to be a feedback mechanism. Answer: positive 90) Insulin lowers blood sugar. If insulin levels are high shortly after a meal, we can conclude that insulin secretion is regulated by feedback mechanisms. Answer: negative 91) Progesterone enters cells by diffusion but stimulates gene transcription only in its target cells. Thus, progesterone can be classified as a hormone. Answer: steroid 92) Cortisol and aldosterone are secreted by the

Answer: adrenal cortex (or adrenal gland) 93)

is the hormone that stimulates the liver to convert glycogen to glucose. Answer: Glucagon

94) Surgical removal of the longer be produced.

would completely disrupt glucose metabolism because insulin would no

Answer: pancreas 95) The heart secretesthe hormone water.

, which lowers blood pressure by increasing the excretion of salt and

Answer: atrial natriuretic peptide (or ANP) 96)

is a hormone produced by the kidneys that increases the rate of red blood cell production. Answer: Erythropoietin

97) The hormone

, produced by the pineal gland, may be involved in sleep-wake cycles in humans.

Answer: melatonin 98) Leptin is releasedfrom

and appears to play a role in fat storage.

Answer: fat cells 99)

from the adrenal medulla increases the heart and respiratory rates, raises blood pressure, and increases blood glucose levels. Answer: Epinephrine (or Norepinephrine)

100) ADH and oxytocin are produced by neurosecretory cells of the released from the .

; however, they are stored in and

Answer: hypothalamus; posterior pituitary 101) Individuals suffering from

produce insulin; however, their cells fail to respond.

Answer: type 2 diabetes 102) A lack of

in the diet can lead to the formation of an enlarged thyroid or goiter.

Answer: iodine 103) Testosterone is produced by the

and the adrenal cortex.

Answer: testes 104) What is a target cell? Answer: A cell that has receptors for a specific hormone 105) Why do hormones affect some cells but not others? Answer: Cells respond only to those hormones for which they have receptors. 106) How does aspirin help to stop pain? Answer: Aspirin blocks prostaglandin production, and prostaglandins are associated with pain sensations. 107) If a person gets a shot of epinephrine, he or she almost immediately feels the effects (e.g., increased heart and breathing rates). If the same person gets a shot of a steroid hormone such as cortisone, there is no immediate response. What is the reason for this difference? Answer: Epinephrine is water soluble and causes an immediate response, whereas steroid hormones cause a slower change by stimulating gene transcription. 108) What is meant by the phrase "cyclic AMP acts as a second messenger"? Answer: Cyclic AMP is an intracellular messenger that is activated by the first messenger (hormone). It can then transfer this message to other molecules within the target cell that enable it to respond. 109) Ecdysone is a hormone that causes molting of the exoskeleton in insects. Why do ecdysone-based pesticides have no effect onhumans? Answer: Humans lack the cell receptors for ecdysone-based hormones, so these hormones cannot cause changes in our cells. 110) Why do fat-free diets affect the production of steroid hormones? Answer: Steroids are synthesized from cholesterol. Individuals on fat-free diets do not ingest cholesterol, so they cannot make any of the steroid hormones. 111) Why are some people concerned about hormones in cattle feed? Answer: All vertebrate hormones are similar, and there are concerns that extra hormones from the feed may transfer to those people who eat the meat.

112) Anabolic steroids are synthetic steroid hormones that bind to testosterone receptors and stimulate muscle development. This appeals to your weight-lifting roommate who promptly orders the drug online. How would you dissuade your roommate from taking the drug? Answer: Anabolic steroids have numerous adverse effects including a suppressed immune system, increased blood pressure, decreased high-density lipoprotein (HDL), altered mood, and decreased sperm count. 113) Rapid loss of blood may lead to shock and death. What series of events do the kidneys initiate to raise the blood pressure of a person who has been severely cut to prevent shock and subsequent death? Answer: The kidneys produce renin in response to lowered blood pressure. Renin stimulates the production of angiotensin in the bloodstream. Angiotensin constricts arterioles, which decreases bleeding and reduces blood flow to the kidneys so that less water is lost in urine. This results in increased blood volume and thus pressure. 114) Do fat cells function as an endocrine gland? Explain. Answer: Yes, fat cells produce the hormone leptin. 115) Stress increases cortisol secretion. Why would diabetics have problems controlling their blood sugar levels when they are stressed? Answer: One of cortisol's functions is to increase blood sugar levels. Adding stress would increase blood sugar levels beyond normal. 116) Why are pituitary tumors sodangerous? Answer: The pituitary gland secretes many releasing and inhibiting hormones. Over- or underproduction of these hormones disrupts the function of the adrenal gland (via ACTH), the reproductive organs (via LH and FSH), cell metabolism (via TSH), and cell growth (via growth hormone). 117) Explain why oxytocin and prolactin are both necessary for nursing. Answer: Prolactin stimulates the growth of the mammary glands and the production of milk. Oxytocin causes the mammary glands to release their secretions. Both are produced in part by suckling activity of the infant. 118) How does ADH help to prevent dehydration? Answer: ADH increases the permeability of the distal tubules and collecting ducts of the nephrons to water. Thus, water is returned to the bloodstream and a small amount of concentrated urine is produced. 119) The anterior pituitary produces hormones that stimulate other endocrine glands to produce their secretions. What stimulates the anterior pituitary to release its hormones? Answer: Releasing hormones produced by the hypothalamus 120) What is the main function of thyroxine? Answer: To increase the metabolic rate of cells 121) How do insulin and glucagon interact to maintain normal blood sugar levels? Answer: When blood sugar levels are high, insulin secretion increases and glucagon secretion decreases. When blood sugar levels drop, glucagon secretion increases and insulin secretion decreases. 122) Some doctors prescribe synthetic thyroxine for weight loss even when circulating levels are normal. Will this work? What side effects are possible? Answer: Thyroxine increases metabolism and induces weight loss. However, the complications are restlessness, irritability, intolerance to heat, and increased appetite.

123) How do calcitonin and parathyroid hormone interact to regulate blood calcium levels? Answer: They act as antagonists. Calcitonin lowers the level of blood calcium by inhibiting its release from the bones. Parathyroid hormone raises the level of blood calcium by releasing it from the bones. 124) Explain how glucagon raises blood glucose levels. Answer: Glucagon stimulates body cells to burn fat instead of glucose and liver cells to convert stored glycogen into glucose, which is released into the bloodstream. 125) Your boss calls you at midnight to say that you must give a major presentation to clients the following morning. Which gland is stimulated to produce hormones as you begin frantically working on your presentation, and what hormones are produced? Answer: The adrenal medulla produces epinephrine and norepinephrine (adrenalin and noradrenalin), while the adrenal cortex produces cortisol. 126) Explain how blood samples taken from men who have undergone an orchidectomy (removal of the testes) and women have measurable levels oftestosterone. Answer: The adrenal cortex of both sexes secretes small amounts of testosterone. 127) What effect would an "endocrine disruptor" that blocks thyroxine have on amphibians? Answer: Amphibians require thyroxine to trigger metamorphosis. If thyroxine secretion were blocked, then amphibians would fail to undergo metamorphosis and remain in the tadpole form.

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 128) Based on this figure, what does cyclic AMP represent?

A) Membrane receptor B) Cytoplasmic receptor C) Second messenger D) First messenger E) Hormone Answer: C

129) The hormone interaction in this figure is an example of

A) a positive feedback mechanism. B) the effects of endocrine disruptors. C) transmission at a gap junction. D) a negative feedback mechanism. E) blood glucoseregulation. Answer: D

130) You are an endocrinologist. A patient has been referred to you because he is cold all the time, even when the ambient temperature is 75°F. His throat is swollen. He also appears to heal slowly. You immediately suspect that his metabolic rate is slower than normal due to A) decreased parathyroid hormone levels. B) elevated calcitonin levels. C) elevated growth hormone levels. D) elevated insulin levels. E) decreased thyroxine levels. Answer: E 131) When blood glucose levels rise, insulin signals cells to take up glucose, removing it from the blood. Diabetes mellitus is a disorder caused by a dysfunction in the insulin signaling system. There are two types of diabetes. People with type 1 diabetes must take insulin regularly, usually through injection. People with type 2 diabetes are not helped by supplemental insulin. What does this tell you about where the defect might be in these two disorders? A) Type 1 diabetes is probably caused by defective insulin receptors. B) Type 2 diabetes is probably caused by overproduction of insulin. C) Type 2 diabetes is probably caused by underproduction of insulin. D) Type 1 diabetes is probably caused by underproduction of insulin. Answer: D 132) Charlie is a hypochondriac. He's always worried he has something. Is that cough an early sign of lung cancer? He's thirsty; is it diabetes? He can't shake hands because he might pick up flu germs. He disinfects everything. Yet, despite his almost obsessive precautions, he comes down with one bug after another. Can you give a plausible explanation? A) Charlie has a goiter, which is increasing his immune response. B) Stress releases cortisol, and cortisol suppresses the immune system. C) Charlie is producing too much growth hormone, which is exhausting his system. D) He's just imagining that he is sick. E) The cough indicates that he is probably diabetic and that makes him susceptible to illness. Answer: B 133) An 8-year-old boy is brought to the endocrinologist for testing. He is already as tall as an adult man. His muscles are well developed, and he has little body fat despite eating huge amounts of food. Blood work shows elevated levels of glucose. The endocrinologist should suspect A) elevated estrogen levels. B) elevated testosterone levels. C) elevated growth hormone levels. D) decreased thyroxine levels. E) elevated parathyroid hormone levels. Answer: C

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Which portion of the neuron typically receives information? A) Cell body B) Glia C) Synaptic terminal D) Axon E) Dendrite Answer: E 2) Electrical signals are transmitted to the synaptic terminals along the A) cell body. B) axon. C) dendrite. D) synapse. E) glia. Answer: B 3) Select the path an electrical signal would take within a single neuron. A) Synaptic terminal → axon → cell body → dendrite B) Dendrite → cell body → axon → synaptic terminal C) Cell body → dendrite → axon → synaptic terminal D) Synaptic terminal → dendrite → axon → cell body E) Synaptic terminal → cell body → axon → dendrite Answer: B 4) The junction across which electrical signals are passed from a neuron to a muscle fiber, a gland, or another neuron is called the A) dendrite. B) synapse. C) soma. D) axon. E) glia. Answer: B 5) Axons A) process information. B) form the gray matter of the brain and spinal cord. C) carry action potentials. D) receive information from the external environment. E) have receptors for neurotransmitters. Answer: C 6) In an unstimulated neuron, the A) K+ B) Ca2+

concentration is higher inside the cell than outside.

C) Cl− D) Li+ E) Na+ Answer: A

7) At the synapse, some neurotransmitters open ion channels that make the interior of the postsynaptic neuron more negative. Thus, these neurotransmitters produce a(n) postsynaptic potential (IPSP). A) decreasing B) rewarding C) inhibitory D) excitatory E) enhancing Answer: C 8) In an unstimulated neuron, the plasma membrane is most permeable to A) sodium (Na+) B) sugar C) potassium (K+) D) calcium (Ca2+)

ions.

E) chloride (Cl−) Answer: C 9) Action potentials are generated when A) resting K+ channels

suddenly open.

B) sodium-potassium pumps C) resting Na+ channels D) voltage-gated K+ channels E) voltage-gated Na+ channels Answer: E 10) The resting potential of an unstimulated neuron is between A) −400 and −900 B) −40 and −90 C) −4 and −9 D) 40 and 90 E) 4 and 9

millivolts (mV).

Answer: B 11) Myelin speeds the conduction of action potentials along a neuron by A) lowering the threshold at which action potentials are generated. B) inserting additional voltage-gated K+ channels into the membrane. C) increasing the resting membrane potential. D) allowing the action potential to "jump" over sections of the axon. E) increasing the diameter of the axon. Answer: D 12) In an unstimulated neuron, thesodium-potassiumpump maintains theconcentration gradientof sodiumand potassium ions by transporting A) sodium and potassium into thecell. B) potassium ions into and sodium ions out of the cell. C) sodium and potassium out of the cell. D) potassium ions out of and sodium ions into the cell. E) sodium and potassium ions in both directions across the cell membrane. Answer: B

13) What happens when the resting potential reaches threshold voltage? A) Resting potassium channels close. B) Voltage-gated sodium channels open. C) Voltage-gated sodium channels close. D) The sodium-potassium pump is turnedon. E) Voltage-gated potassium channels open. Answer: B 14) Nicotine affects neurotransmission by causing more action potentials in the presynaptic neuron and by causing more neurotransmitter to be released per vesicle. This means your postsynaptic neurons A) are harder than normal to stimulate in the presence of nicotine. B) cannot be stimulated at all in the presence of nicotine. C) are unaffected by nicotine. D) are uncoordinated in the presence of nicotine. E) are more easily stimulated in the presence of nicotine. Answer: E 15) During the repolarization phase of an action potential, the membrane potential falls from +60 to -70 mV. This drop is due mostly to the movement of ions. A) hydrogen B) calcium C) sodium D) potassium E) chloride Answer: D 16) Activity of the neurotransmitter acetylcholine is brief because it A) is transported back into the presynaptic neuron. B) is pumped out of the synaptic cleft by the sodium-potassium pump. C) "self-destructs" shortly after leaving the presynaptic neuron. D) diffuses out of the synapticcleft. E) is rapidly broken down by enzymes in the synaptic cleft. Answer: E 17) The brain and spinal cord interpret the frequency of action potentials they receive as A) divergence. B) a reflex. C) convergence. D) stimulus intensity. E) stimulus importance. Answer: D 18) The intensity of a stimulus is indicated by the A) frequency B) duration C) intensity D) loss E) speed

of action potentials.

Answer: A

19) Which stimulus would the brain interpret as the strongest? A) 5 action potentials per second B) 10 action potentials per second C) 20 action potentials per second D) 100 action potentials per second E) 50 action potentials per second Answer: D 20) If a bone fragment resulting from a broken nose pushed against the olfactory (smell) nerve, triggering an action potential, the person would A) register the sensation as asmell. B) lose her sense of smell. C) register the sensation as a visual stimulus. D) register the sensation as asound. E) not register the sensation at all. Answer: A 21) Motor neurons A) receive stimuli from inside or outside the body. B) carry impulses to the brain. C) send signals to effectororgans. D) integrate information from many sources. E) transmit impulses toward the spinal cord. Answer: C 22) A diffuse nerve net would be found in which of the following animals? A) Jellyfish B) Human C) Insect D) Flatworm E) Octopus Answer: A 23) Which of the following is part of the peripheral nervous system? A) Spinal cord B) Autonomic nervous system C) Medulla D) Thalamus E) Brain Answer: B 24) The autonomic nervous system consists of two parts: the sympathetic and parasympathetic divisions. The sympathetic division is responsible for which type of response? A) Constriction of the air passages in the lungs B) Stimulation of digestion C) Rest-and-digest responses D) Slowing of the heart rate E) Fight-or-flight responses Answer: E

25) Of the following structures, which can be found in the human peripheral nervous system? A) Spinal cord B) Cerebrum C) Sensory neurons D) Hypothalamus E) Cerebellum Answer: C 26) Most brain and spinal cord cells are A) interneurons. B) saltatory neurons. C) parasympathetic neurons. D) motor neurons. E) sensory neurons. Answer: A 27) The cell bodies of motor neurons are located A) in the gray matter of the spinal cord. B) in the muscles. C) next to the sensoryreceptors. D) in the forebrain. E) outside the spinal cord. Answer: A 28) Taking a nap after meals is probably a good idea because it allows the body to digest the food as a result of the activities of the nervous system. A) parasympathetic B) sympathetic C) sensory D) central E) somatic Answer: A 29) Which of the following does NOT describe the autonomic nervous system? A) It forms synapses with smooth muscles in blood vessels. B) It regulates heart rate. C) It is subdivided into sympathetic and parasympathetic divisions. D) It controls voluntary movements. E) Neurons release norepinephrine or acetylcholine onto their target organ. Answer: D 30) Which of these neurotransmitters, released by neurons of the sympathetic nervous system, helps prepare the body for energetic activity? A) Serotonin B) Dopamine C) Norepinephrine D) Endorphin E) Acetylcholine Answer: C

31) While walking barefoot along the beach, you step on a shard of glass and reflexively lift your injured foot. Which path did the reflex to lift your foot take? A) Motor nerve → spinal cord → brain → spinal cord → sensory nerve → effector B) Sensory nerve → spinal cord → motor nerve → effector C) Sensory nerve → spinal cord → brain → spinal cord → motor nerve→ effector D) Motor nerve → sensory nerve → spinal cord → brain E) Sensory nerve → motor nerve → spinal cord → brain Answer: B 32) Dolphinsuseecholocation to maneuveraroundobjectsquicklyandprecisely to captureprey. Thus, youwould expect them to have a larger-than-normal A) limbic system. B) amygdala. C) cerebellum. D) hypothalamus. E) cerebrum. Answer: C 33) A functioning would enable you to read a novel while sitting in a noisy restaurant. A) substantia nigra B) reticular formation C) hypothalamus D) thalamus E) cerebrum Answer: B 34) Which region of the brain controls breathing and heart rate? A) Cerebellum B) Medulla C) Cerebrum D) Thalamus E) Hypothalamus Answer: B 35) All sensory information, with the exception of olfaction, must pass though the cerebral cortex. A) hypothalamus B) cerebellum C) reticular formation D) amygdala E) thalamus

as it travels tothe

Answer: E 36) Addictive drugs that make people feel good, such as cocaine and methamphetamine, block the uptake of which of the following neurotransmitters in the brain? A) GABA B) Serotonin C) Nitric oxide D) Dopamine E) Acetylcholine Answer: D

37) Glutamate is the major excitatory neurotransmitter in the brain. Which drug produces a relaxing effect by blocking the receptors for glutamate? A) Alcohol B) Methamphetamine C) Cocaine D) Nicotine E) Caffeine Answer: A 38) Which region of the brain is responsible for the intricate coordination of finger movements involved in playing the piano? A) Pons B) Midbrain C) Cerebrum D) Hypothalamus E) Cerebellum Answer: E 39) Which portion of the brain is responsible for primitive emotions such as fear, rage, and sexual desire? A) Limbic system B) Medulla C) Pons D) Reticular formation E) Thalamus Answer: A 40) The coordinates muscle movements of thebody. A) cerebrum B) parietal lobe C) hypothalamus D) medulla E) cerebellum Answer: E 41) When you hear a loud noise, you immediately turn your head and direct your eyes toward the sound. Which region of the brain directs this reflexive movement of your eyes? A) Midbrain B) Pons C) Hindbrain D) Hippocampus E) Cerebrum Answer: E 42) Which region of the brain helps regulate body temperature, endocrine activity, and water balance? A) Cerebrum B) Cerebellum C) Thalamus D) Hypothalamus E) Medulla Answer: D

43) Sensory information processing as well as the direction of voluntary movements are carried out by the A) amygdala. B) cerebrum. C) medulla. D) cerebellum. E) hypothalamus. Answer: B 44) Damage to the right frontal cortex may produce paralysis on the A) dominant B) nondominant C) left D) right

side of the body.

Answer: C 45) To survive the winter, some birds, such as the black-capped chickadee, must locate caches of seeds it buries each fall. Which region of the brain allows the birds to remember the exact locations of these stashes? A) Frontal lobe B) Amygdala C) Occipital lobe D) Hypothalamus E) Hippocampus Answer: E 46) The corpus callosum links the A) peripheral and central nervous systems. B) right and left cerebral hemispheres. C) cerebrum and thalamus. D) thalamus and hypothalamus. E) forebrain and midbrain. Answer: B 47) The right cerebral hemisphere A) controls movements of the left side of the body. B) is smaller in women thanmen. C) controls movements of the right side of the body. D) is logical. E) is slightly larger than the left cerebral hemisphere. Answer: A 48) John was attending a party when he suddenly started eating food from some of the other guest's plates and using profane language. John's son promptly rushed his father to the hospital where it was discovered that he had suffered a stroke. Based on John's altered behaviors, which area of the brain was most likely damaged by the stroke? A) cerebellum B) Corpus callosum C) Temporal lobe D) Hypothalamus E) Prefrontal cortex Answer: E

49) People with damage to the hippocampus seem to be unable to remember recent events even though their memory of events before the damage remains intact. This seems to indicate that the hippocampus is involved in A) transferring information from short-term memory into long-term memory. B) retrieving memories. C) generating new neurons in the cerebellum. D) recognizing similar events. E) producing hormones that control the memory neurons of the cerebrum. Answer: A 50) It is possible that brain damage from a stroke or other injury could leave a person with the ability to comprehend written language but not spoken language (assume the person's hearing is fine). Which statement best explains this? A) The same region of the brain controls all aspects of language comprehension. B) Different cells of the frontal cortex control different aspects of language comprehension. C) The ability to understand written language is controlled by the left cerebral hemisphere, whereas the ability to understand spoken language is controlled by the right cerebral hemisphere. D) Different parts of the brain are involved in different aspects of language comprehension. Answer: D 51) If a patient has a particular memory problem in which he can recall old memories but cannot make new memories, what part of his brain is most likely damaged? A) Prefrontal cortex B) Hippocampus C) Temporal lobes D) Thalamus E) Basal ganglia Answer: B 52) Alice's PET (positron emission tomography) scan shows a large red area in the occipital lobe when taken while Alice is looking at color images. Which of the following is TRUE about Alice's PET scan? A) The darkest areas of Alice's brain were the mostactive. B) The occipital lobe had the highest level of activity. C) The occipital lobe was the only area of Alice's brain that was active. D) This scan proves the old saying that we use only 10% of our brains. Answer: B 53) After an accident, a professional musician cannot associate any of the instruments he has played with the sounds they make. What part of his brain is most likely damaged? A) Primary sensory areas B) Auditory association areas C) Basal ganglia D) Primary auditory areas E) Sensory association areas Answer: B

54) Visual information is processed inthe A) hippocampus. B) parietal lobes. C) temporal lobes. D) frontal lobes. E) occipital lobes. Answer: E 55) The is a cluster of neurons that plays a role in wake-sleep cycles, muscle tone, emotions, and some reflexes. A) medulla B) cerebral cortex C) reticular formation D) hypothalamus E) pons Answer: C 56) The left and right hemispheres of the brain are connected through the A) hypothalamus B) reticular formation C) pons D) medulla E) corpus callosum

, a large band ofaxons.

Answer: E 57) Sensations of fear, pleasure, and sexual arousal are produced by the A) hypothalamus. B) reticular formation. C) cerebral cortex. D) amygdala. E) medulla. Answer: D 58) You arrive ten minutes late for your final exam and immediately regret stopping for donuts, which feel like a dead weight in your stomach. Your heart is pounding and your palms are sweaty. What part of your nervous system is in control? A) Sympathetic B) Voluntary C) Parasympathetic D) Somatic E) Nerve net Answer: A 59) Dendrites release neurotransmitters at synapses. A) True B) False Answer: B

60) Nerves are groups of axons bundled together. A) True B) False Answer: A 61) Myelinated axons conduct action potentials more slowly than axons without a myelin covering. A) True B) False Answer: B 62) A neuron's resting potential is due in large part to the diffusion of K+ ions out of the cell, leaving the negatively charged DNA and proteins inside the cell. A) True B) False Answer: A 63) As the resting membrane potential of a neuron nears threshold, it becomes harder to stimulate. A) True B) False Answer: B 64) At a chemical synapse, the presynaptic and postsynaptic neurons touch and chemicals are exchanged through gap junctions. A) True B) False Answer: B 65) The concentrations of ions inside and outside of a neuron are maintained by sodium-chloride (Na+-Cl−) pumps. A) True B) False Answer: B 66) An influx of calcium ions causes vesicles to fuse with the presynaptic membrane and release neurotransmitter into the synapse. A) True B) False Answer: A 67) The stronger the stimulus, the more powerful the action potential. A) True B) False Answer: B 68) The integration of excitatory postsynaptic potentials (EPSPs) and inhibitory postsynaptic potentials (IPSPs) received by a postsynaptic neuron determines its activity. A) True B) False Answer: A

69) The brain is able to take sensory inputs from many neurons, integrate them, and determine an appropriate response. A) True B) False Answer: A 70) The more frequently an action potential is triggered by a stimulus, the greater the intensity of the sensation. A) True B) False Answer: A 71) Effectors pick up sensory stimuli. A) True B) False Answer: B 72) Interneurons connect sensory and motorneurons. A) True B) False Answer: A 73) The more complex the organism, the more likely it is to have nerve net. A) True B) False Answer: B 74) The peripheral nervous system consists of the brain and spinal cord. A) True B) False Answer: B 75) Smooth muscle responses are controlled by the somatic nervous system. A) True B) False Answer: B 76) A good meal and a pleasant evening relaxing in front of the fire trigger the parasympathetic nervous system. A) True B) False Answer: A 77) Sympathetic and parasympathetic nervous system responses usually oppose each other. A) True B) False Answer: A 78) The control centers for breathing, blood pressure, and heart rate are located in the medulla. A) True B) False Answer: A

79) The hippocampus is responsible for processing sensory stimuli. A) True B) False Answer: B 80) Emotions and the responses to emotions are controlled by the limbic system. A) True B) False Answer: A 81) A neurotransmitter associated with pleasurable feelings is dopamine. A) True B) False Answer: A 82) GABA is a neurotransmitter in the brain that can be affected by alcohol use. A) True B) False Answer: A SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 83) The part of a neuron that contains a nucleus and other organelles typical of cells is the

Answer: cellbody 84) Neurons release chemicalsknown as

into a synapse to convey signals to adjacent cells.

Answer: neurotransmitters 85) The interior of an unstimulated neuron maintains a constant negative charge, called the

Answer: restingpotential 86) A neuron generates a(n)

when stimuli reach or exceed the neuron's threshold.

Answer: actionpotential 87) A(n) postsynaptic potential is initiated when neurotransmitter binding to receptor proteins causes the postsynaptic neuron to become less negative. Answer: excitatory 88) The brain interprets the of light on the basis of the number and frequency of action potentials it receives from light receptors in the retina. Answer: intensity 89)

transmit signals from the central nervous system to the effector organs. Answer: Motorneurons

90) Complex organisms tend tohave a

nervous system with sense organs concentrated in the head.

Answer: centralized 91) The dorsal root ganglia of the spinal cord contain cell bodies of Answer: sensory 13

neurons.

92) The pleasurable effects of cigarette smoking are due to an increase in the release of the neurotransmitter . Answer: dopamine 93) The reflexes.

is a cluster of neurons that plays a role in wake-sleep cycles, muscle tone, emotions, and some

Answer: reticular formation 94) The left and right hemispheres of the brain are connected through the

, a large band of axons.

Answer: corpuscallosum 95) Sensations of fear, pleasure, and sexual arousal are produced by the

Answer: amygdala 96) Individuals diagnosed with Huntington's disease exhibit abnormal involuntary movements due to deterioration of the . Answer: basal ganglia 97) Neurons receive, process, and transmit information; however, they cannot function without glia. What are glia, and how do they affect neuronal functioning? Answer: Glia are nervous system cells that provide nutrients for neurons, maintain an appropriate chemical environment for neuronal signaling in the brain and spinal cord, modulate communication between neurons, and insulate axons. 98) People with multiple sclerosis develop areas in which the myelin sheath on their neurons has disintegrated. This disease often results in paralysis and extreme weakness. Using what you know about the myelin sheath, explain why these symptoms mightoccur. Answer: The myelin sheath enables nerve conduction to occur at a much more rapid rate than without it; thus impulses travel more slowly to and from the brain, contributing to the symptoms. 99) Individuals with viral hemorrhagic fever lose the ability to regulate their K+ levels. Why does this condition create neurological problems? Answer: Potassium plays a major role in maintaining the membrane potentials that are responsible for keeping the nerves working. Without the proper K+ levels, normal neurological function fails. 100) Why do negatively charged molecules tend to remain inside both an unstimulated and stimulated neuron? Answer: Most negatively charged molecules are large organic molecules such as proteins and ATP, which cannot cross the membrane. 101) If neurotransmitter binding to receptors on a postsynaptic neuron generates an IPSP, what happens? Answer: The resting potential of the postsynaptic neuron moves farther away from threshold, making it less likely to generate an action potential. 102) What causes a nerve impulse to travel along the membrane? Answer: The positive charge of an action potential spreads quickly to the next part of the axon, causing it to reach an action potential as well.

103) A person responds to touching a hot pan by pulling his hand away before he feels pain. Why does it take longer for him to feel pain? Answer: The withdrawal reflex goes to and from the spinal cord before the message has time to get to the brain. Pain is interpreted in the brain. 104) You have just completed final preparations for a party you are hosting this evening. With thirty minutes to spare, you collapse into a chair and prop your feet up only to realize you need to empty your bladder. What part of your nervous system is in control? Answer: Parasympathetic nervous system 105) What is the function of cerebrospinal fluid? Answer: To cushion the brain and spinalcord 106) A person who is unable to speak after a stroke has had damage to what part of the brain? Answer: Frontal lobe/cerebrum/cerebral cortex 107) How are the sympathetic and parasympathetic nervous systems similar? Answer: They control involuntary actions and innervate many of the same organs. The sympathetic system prepares for action, whereas the parasympathetic system allows for relaxation. There are also differences in the anatomy of thesystems. 108) Explain why most adults do not have to think about how to walk even though they did when they were toddlers. Answer: All the neurons and connections needed for walking are in the spinal cord. What the brain contributes after the person learns to walk is the initiation of the activity. 109) Individuals using drugs such as cocaine over extended periods of time find that they need increasing amounts just to feel okay. Why? Answer: Drugs such as cocaine reduce the number of dopamine receptors and increase the number of dopamine pumps.

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

110) What part of the neuron is labeled "Section 1"? A) Synaptic terminal B) Cell body C) Dendrite D) Myelin E) Axon Answer: C 111) Which of the following does NOT occur at "Section 2"? A) Neurotransmitter binds to receptor of "receiving" cell B) Neurotransmitter diffuses across synapse C) Integration of the signal D) Release of neurotransmitter by "sending" cell E) Transmission of the signal Answer: C

112) In the above graph, which of the following causes the slight increase in voltage at point 2? A) Na+ entering the neuron B) Cl− entering the neuron C) K+ leaving the neuron D) K+ entering the neuron E) Na+ leaving the neuron Answer: A 113) Identify the numbered region in the above graph that indicates the action potential. A) 1 B) 2 C) 3 D) 4 E) 5 Answer: D

114) What type of nervous system is exhibited by the hydra? A) Hydra doesn't have a nervous system B) Diffuse nervous system C) Peripheral nervous system D) Centralized nervous system E) Somatic nervous system Answer: B

115) What type of nervous system does the flatworm exhibit? A) The flatworm doesn't have a nervous system B) Diffuse nervous system C) Peripheral nervous system D) Somatic nervous system E) Centralized nervous system Answer: E 116) A person you know has been in an automobile accident. The accident caused a dramatic personality change. Before the accident, he was industrious and well liked; after the accident, he is profane, impetuous, and incapable of working toward a goal. Which portion of the brain was most likely damaged? A) Parietal lobe B) Temporal lobe C) Hypothalamus D) Frontal lobe E) Hippocampus Answer: D 117) Marta has been having terrible headaches. Now her hand feels like it is being gripped even though it is not actually being touched. She's also having a hard time interpreting sensations. For example, she blistered her hand on a hot pan because she interpreted the heat sensation as cold. Which portion of Marta's brain is most likely damaged? A) Hypothalamus B) Hippocampus C) Temporal lobe D) Frontal lobe E) Parietal lobe Answer: E 118) You just finished watching a scary movie and decide to take the trash out before going to bed. Halfway down the driveway, the streetlight goes out and something rattles the trashcans, just like in the movie before the monster attacked. Suddenly, the neighbor's cat jumps up onto the top of the trashcan and you shriek. Your increased heart rate is in response to the neurotransmitter A) GABA. B) oxytocin. C) norepinephrine. D) acetylcholine. E) glutamate. Answer: C

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) A cell specialized to respond to a particular type of stimulus is a A) corpuscle. B) sensory receptor. C) sensoryreceiver. D) saccule. E) pinna. Answer: B 2) Cones are specialized to detect which of the following types of stimuli? A) Taste B) Heat and cold C) Vibration D) Light E) Odor Answer: D 3) Chemoreceptors include A) rods. B) olfactory receptors. C) hair cells. D) free nerve endings. E) Pacinian corpuscles. Answer: B 4) Sensory receptors are grouped into categories based on the A) types of action potentials theygenerate. B) stimuli to which they respond. C) part of the central nervous system to which they connect. D) brain cells they stimulate. Answer: B 5) A stimulus that is strong enough to trigger an action potential is said to be above A) maximum. B) frequency. C) capacity. D) intensity. E) threshold. Answer: E 6) The strength of a stimulus is indicated by the A) loss B) speed C) duration D) intensity E) frequency

of action potentials.

Answer: E

7) Receptor potentials may generate action potentials in the receptor cell itself, or they may cause stimulates an associated neuron to generate action potentials. A) the production of glucose B) an influx of ClC) a change in pressure D) an increase in blood flow E) the release ofneurotransmitter Answer: E 8) Receptor potentials are A) directly proportional to B) inversely proportional to C) the same regardless of D) unrelated to E) much greater than

the strength of the stimulus.

Answer: A 9) Odor molecules stimulate responses in A) hair cells. B) rods. C) olfactory receptors. D) stretch receptors. E) free nerve endings. Answer: C 10) Which of the following chemical compounds stimulate cold receptors in the skin and oral cavity? A) Clove oil B) Monosodium glutamate (MSG) C) Camphor D) Menthol E) Capsaicin Answer: D 11) All of the following are examples of mechanoreceptors EXCEPT A) Meissner's corpuscles. B) Ruffini corpuscles. C) Pacinian corpuscles. D) olfactory receptors. E) stretch receptors. Answer: D 12) Which type of receptor signals that your stomach is full after a big meal? A) Mechanoreceptor B) Thermoreceptor C) Photoreceptor D) Chemoreceptor Answer: A

that

13) Which of the following will respond to steady pressure? A) Hair cells B) Ruffini corpuscles C) Meissner's corpuscles D) Olfactory receptors E) Pacinian corpuscles Answer: B 14) Your best friend sneaks up behind you and lightly strokes the back of your neck with a feather. Which of the following receptors would detect this type of stimulus? A) Pacinian corpuscles B) Hair cells C) Stretch receptors D) Meissner's corpuscles E) Ruffini corpuscles Answer: D 15) Hair cells in the human ear are located on the A) basilar membrane. B) tympanic membrane. C) pinna. D) round window. Answer: A 16) Which of these structures can be swiveled around in some animals to better locate a sound? A) Hammer B) Anvil C) Pinna D) Cochlea Answer: C 17) The malleus is also called the A) cochlea. B) stirrup. C) pinna. D) anvil. E) hammer. Answer: E 18) Which structure transmits sound waves to the malleus in the middle ear? A) Cochlea B) Vestibular membrane C) Pinna D) Auditory membrane E) Tympanic membrane Answer: E

19) The perception of sound dependson A) thermoreceptors. B) photoreceptors. C) nociceptors. D) chemoreceptors. E) mechanoreceptors. Answer: E 20) If the doctor says you have a middle ear infection, which of the following could be involved? A) Vestibular apparatus B) Cochlea C) Auditory tube D) Pinna Answer: C 21) How do we perceive the pitch of sounds? A) Rods vibrate in response to high-frequency sounds and cones respond to low-frequency sounds. B) Different parts of the basilar membrane vibrate in response to different frequencies of sound. C) The hammer, anvil, and stirrup vibrate at different speeds. D) The tympanic membrane vibrates more strongly at high frequencies. E) The pinna swivels in different directions in response to sounds of different frequency. Answer: B 22) The hammer, anvil, and stirrup are located in the A) inner ear. B) middle ear. C) auditory canal. D) outer ear. E) cochlea. Answer: B 23) The receptor cells for hearing are located in the A) cochlea. B) utricle. C) semicircular canals. D) auditory tube. E) saccule. Answer: A 24) Select the correct path through which sound waves travel to stimulate hearing. A) Outer ear → oval window → middle ear → tympanic membrane → cochlea B) Outer ear → tympanic membrane → middle ear → oval window → cochlea C) Outer ear → tympanic membrane → auditory tube → cochlea → oval window D) Outer ear → auditory tube → oval window → tympanic membrane → basilar membrane E) Outer ear → basilar membrane → inner ear → oval window → auditory tube Answer: B

25) Vibration of the stirrup against this membrane transmits sound waves into the fluid-filled cochlea. A) Round window B) Tympanic membrane C) Basilar membrane D) Oval window E) Tectorialmembrane Answer: D 26) The frequency of a sound wave determines the A) tone B) amplitude C) loudness D) pitch

of the sound you hear.

Answer: D 27) Which of the following has the greatest potential to damage hair cells after prolonged exposure? A) Noisy restaurant B) MP3 player C) Two humans talking D) A car engine E) Noise from an urban street Answer: B 28) After 20 years on the road, Roger recently retired as the drummer of a rock band. It didn't take long for Roger to realize that he was unable to hear as well as he used to. Roger's diminished hearing is most likely due to damage of A) hair cells. B) the hammer and anvil. C) the tympanic membrane. D) corpuscles. E) the auditory nerve. Answer: A 29) The hair-like projections of the hair cells are inserted into the A) oval window. B) round window. C) tectorial membrane. D) tympanic membrane. E) basilar membrane. Answer: C 30) The tiny stones in the vestibule, which move in response to gravity, are made of A) calcium hydroxide. B) magnesium. C) iron oxide. D) sodium chloride. E) calcium carbonate. Answer: E

31) The hair cellsin the detect the direction of gravity. A) corpuscle B) utricle and saccule C) oval and round windows D) middle ear Answer: B 32) The detect movement of the head. A) semicircular canals of the innerear B) pinna and auditory canal of the outer ear C) oval and round windows of the inner ear D) olfactory receptors in the nasalcavity E) bones in the middle ear Answer: A 33) How many semicircular canals are in the inner ear of the right ear? A) One B) Two C) Three D) Four Answer: C 34) The many individual light-sensitive subunits in an insect's eye are called A) ommatidia. B) cones. C) rods. D) ganglion cells. E) corpuscles. Answer: A 35) The white of the human eye's exterior is actually the A) fovea. B) retina. C) iris. D) pupil. E) sclera. Answer: E 36) You are researching the adaptations of a newly discovered mammal that is active mostly at night. Which adaptation to the eye would you expect to find? A) Thicker vitreous humor behind thelens B) An eyespot that can only discern light from dark C) Crustacean flattened cornea resulting in farsightedness D) A reflective choroid behind theretina E) Many individual light-sensitive subunits in each eye Answer: D

37) Ommatidia are found in the compound eyes of A) mollusks. B) flatworms. C) humans. D) amphibians. E) insects. Answer: E 38) When light energy hits a photopigment, the molecule A) generates an action potential. B) forms an enzyme. C) changes shape, setting off a series of chemical reactions. D) is destroyed, setting off a series of chemicalreactions. E) is separated from the plasma membrane. Answer: C 39) Why do your parents or grandparents most likely need glasses to read? A) The photoreceptors of the eye are no longer as responsive. B) The lens of the eye becomes rounder with age. C) The optic nerve sends signals more slowly as people age. D) The lens of the eye stiffens with age, making it difficult to focus on nearby objects. E) They have spent more time reading books at close range than have younger people. Answer: D 40) Which of the following animals has an eye with a single lens? A) Human B) Jellyfish C) Butterfly D) Dragonfly E) Bee Answer: A 41) The receptor cells affected by light rays contain molecules called A) ganglia. B) ampullae. C) photopigments. D) ommatidia. E) mechanoreceptors. Answer: C 42) Which is the correct sequence of structures through which light passes in the eye? A) Lens → pupil → cornea → aqueous humor → retina B) Cornea → aqueous humor → pupil → lens → vitreous humor → retina C) Aqueous humor → cornea → lens → pupil → retina → vitreous humor D) Pupil → vitreous humor → aqueous humor → retina → cornea E) Lens → cornea → vitreous humor → retina → aqueous humor → pupil Answer: B

43) The fovea of the human eye A) contains mostlyrods. B) is located in the sclera. C) is the part of the retina that produces the sharpest image. D) is also known as the blind spot. E) contains a high concentration of ommatidia. Answer: C 44) In humans, when the eye focuses on a nearby object, the lens A) does not change. B) becomes more rounded. C) gets more transparent. D) flattens. E) gets less transparent. Answer: D 45) In a person who is nearsighted, the A) lens is not functional atall. B) incoming light is focused in front of the retina. C) aqueous humor is cloudier than normal. D) muscle that controls the thickness of the lens is weak. E) eyeball is too short from front to back. Answer: B 46) The optic nerve A) interprets the action potentials it carries. B) connects the two eyes. C) carries action potentials that originate in the retina. D) forms a blind spot at the fovea. E) is made up of hair cells. Answer: C 47) What is the blindspot? A) An area of the retina that has no receptor cells B) A part of the cornea C) The hole where there is no iris D) A space in the vitreoushumor E) The part of the cerebral cortex that interprets action potentials from the eye Answer: A 48) People who wear contact lenses or glasses have a defect in the A) cone cells. B) blind spot. C) iris. D) rod cells. E) length of the eyeball. Answer: E

49) Why do things appear mainly black or white to us in low light? A) Only white light is available at night. B) Few action potentials are generated in low light. C) The diffused light of night does not fall on the fovea. D) Colored light does not strike the retina in low light. E) Rods are more sensitive to light than are cones. Answer: E 50) Which of the following is NOT a type of cone found in the human retina? A) Green B) Blue C) Yellow D) Red Answer: C 51) In humans, depth perception is possible because A) each of the two eyes "sees" an entirely different image. B) the two eyes see identicalimages. C) the two eyes have overlapping visual fields. D) the two eyes are necessary for any vision to occur. E) we have two eyes on the sides of our heads. Answer: C 52) If you could monitor the activity from the photoreceptors of rods and cones in the retina during a dream, would you expect these cells to be producing electrical signals? Why? A) No, because rods and cones never produce electrical signals. B) No, because rods and cones only convert light energy into electrical signals. C) Yes, because our eyes move during sleep, and this stimulates the rods and cones. D) Yes, because the rods and cones are reproducing images that are then sent to the brain. Answer: B 53) The provides nourishment for the lens and cornea. A) aqueous humor B) choroid C) optic nerve D) retina E) vitreous humor Answer: A 54) The round shape of the eyeball is maintained by the gel-like A) choroid. B) cornea. C) iris. D) vitreous humor. E) aqueous humor. Answer: D

55) Your friend has trouble distinguishing the color red from the color green. You explain that he is color-deficient because his eyes A) have rods but no cones. B) are too elongated or have a cornea that is too round. C) do not have the photopigments stimulated by red or green light. D) were damaged by bright sunlight. E) have larger blind spots than normal. Answer: C 56) What is the effect of a cornea that is too flat? A) Nearsightedness B) An enlarged blind spot C) Farsightedness D) Blindness Answer: C 57) MSG is often used as a seasoning to enhance the flavors of meat, fish, and vegetables. Which type of taste receptor cell responds to MSG? A) Salty B) Sweet C) Bitter D) Sour E) Umami Answer: E 58) Smell and taste are detectedby A) mechanoreceptors. B) thermoreceptors. C) olfactory receptors. D) chemoreceptors. E) nociceptors. Answer: D 59) Chemicals detected by the nosemust A) bind to taste buds. B) stimulate the cones. C) dissolve in mucus in the nasal cavity. D) first enter the mouth. E) cause bending of hair cells in the upper nasal cavity. Answer: C 60) Odor molecules diffuse through mucus and bind directly to the A) corpuscles B) cell body C) microvilli D) axons E) dendrites Answer: E

of olfactory receptors.

61) Which of the following is responsible for the perception of smell? A) Optic nerve B) Corpuscles C) Olfactory receptors D) Ganglion cells E) Olfactory bulb Answer: E 62) There are different olfactory receptor proteins in humans that allow us to sense a variety of odors. A) 1,000 to 1,500 B) 5 to 10 C) 10 to 15 D) 350 to 400 E) 100,000 to 500,000 Answer: D 63) How many taste buds are on the human tongue? A) 500 B) 5,000 C) 5,000,000 D) 50 E) 5 Answer: B 64) You take a drink of scalding coffee and it burns your tongue. The replace the damaged receptors. A) stem B) supporting C) neuron D) taste E) glial

cells of the taste bud divide to

Answer: A 65) The sense of taste relieson A) both taste buds and olfactoryreceptors. B) taste buds, olfactory receptors, andnociceptors. C) taste buds, olfactory receptors, andmechanoreceptors. D) taste buds only. E) olfactory receptorsonly. Answer: A 66) The threshold of human skin temperature at which cool or cold is perceived as pain is A) 32°F. B) 0°F. C) 59°F. D) -5°F. Answer: C

67) Pain receptors A) are activated when skin temperatures are between 65°F and 100°F. B) respond to bradykinin, which is produced as a result of cell damage. C) are sometimes called photoreceptors. D) do not respond to stretching. Answer: B 68) Spicy foods often contain the chemical capsaicin, which activates certain receptors in the mouth, causing your mouth to feel like it is "burning." The receptors activated by capsaicin are also activated by A) glutamate. B) acidic foods. C) sweet foods. D) salty foods. E) very hot temperatures. Answer: E 69) The stronger the stimulus, the larger the action potential. A) True B) False Answer: B 70) The stronger the stimulus, the larger the receptor potential. A) True B) False Answer: A 71) Human fingertips have the same number of touch receptors per square inch as the skin of the back. A) True B) False Answer: B 72) Ruffini corpuscles respond to a light touch against the skin. A) True B) False Answer: B 73) There are three small bones in the inner ear. A) True B) False Answer: B 74) Binocular vision is an adaptation found in many animals that benefit from good depth perception. A) True B) False Answer: A 75) Sour sensations occur when H+ binds to taste receptor cells. A) True B) False Answer: A

SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 76) Any cell that generates an electrical signal in response to a stimulus is a

receptor.

Answer: sensory 77) The

ear not only detects sound, but also detects gravity and movement.

Answer: inner 78) Optimal color vision occurs in the fovea, a depression in the retina where most of the

are located.

Answer: cones 79) Olfactory receptors are located in the

cavity.

Answer: nasal 80) The five distinctly different tastes that stimulate receptors on the human tongue are , , and .

Answer: sour, salty, sweet, bitter, umami 81) What symptoms indicate that the auditory tube is blocked? Answer: Pressure either increases or decreases within the middle ear cavity because air pressure across the tympanic membrane cannot be equalized. If the pressure is strong enough, it may result in pain. 82) How does the ear distinguish between loud and soft sounds? Answer: The louder the sound, the more the hair cells are bent. Greater bending leads to higher receptor potentials, leading to more frequent action potentials. Frequent action potentials are interpreted as loudness in the brain. 83) Explain how structures within the saccule would respond to descending in an elevator from the fifteenth floor to the third floor? Answer: When the elevator is not moving, the hair cells of the saccule are horizontal and embedded in a gelatinous matrix topped with tiny, calcium carbonate stones. As the elevator descends, the stones are pulled upward, causing the hairs of the hair cells to deflect upward as well. The brain interprets this upward deflection as "going down" in the elevator. 84) How does an insect see the world, as many separate images or as a single image? Answer: Insects see a pixelated image, which probably makes objects appear grainy. 85) What is the blind spot, and why does it occur? Answer: The blind spot is the location in the eye where the axons of the ganglion cells pass through the retina. There are no receptors in this area. 86) What are the two main functions of the choroid layer, located behind the retina in humans? Answer: To supply blood to the retina and to absorb stray light so that it is not reflected inside the eye 87) How is the placement of the eyes of a predator different from their placement on its prey? Answer: Both eyes of a lion are in the front of the face, so that the lion can focus clearly on its prey and have good depth perception. The eyes of prey tend to be on the sides of the head so they can see predators approach from almost any direction.

88) Why does food taste bland when you have a cold? Answer: Much of "taste" is actually smell; when you have a cold, your nose is stuffed up and you cannot smell very well because odor and taste molecules cannot reach the olfactory receptors. 89) Describe the structure of a taste bud. Answer: A taste bud is a cluster of cells (supporting, stem, and taste receptor cells) embedded in papillae on the tongue. A pore connects the center of the taste bud to the surface and allows chemicals to contact microvilli from the receptors. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

90) Which part of the eye shown in the above figure changes shape to focus on objects at different distances? A) A B) B C) C D) D E) E Answer: D 91) In the above figure, which part of the eye contains photoreceptors (rods and cones), signal processing neurons, and ganglion cells? A) A B) B C) C D) D E) E Answer: C

92) Owls have many anatomical modifications that enable them to hunt at night. For example, some of their feathers are serrated on the edges, which eliminate the noise created by air flowing over a smooth feather surface. Owls can thus descend on their prey without a sound. They can locate small prey with remarkable accuracy, even in dim light or complete darkness. Experiments conducted in totally dark, soundproof rooms have shown that owls can capture prey after pinpointing its location to within 1.5 degrees in both horizontal and vertical planes. Based on this scenario, which of these structures do owls primarily rely on when they hunt in total darkness? A) Olfactory bulb B) Nociceptors C) Umami receptors D) Mechanoreceptors E) Photoreceptors Answer: D 93) Optometrists, who help patients with their vision problems, know that certain types of repetitive use of the muscles around the lens of the eye can "train" the lens to become flatter than normal. This often occurs in truck drivers, sailors, and other people who focus on the horizon or at great distances for long periods of time. What would be the consequence of this on the eye over a long time period? A) Nearsightedness B) Farsightedness C) Complete blindness D) Color-deficiency Answer: B 94) Olfactory dysfunction, or dysosmia, is a problem with the sense of smell. Technically, it is a deviation from the normal sensing and perception of odor molecules, or olfactory stimuli processing. There are several different forms of dysosmia, including anosmia (stimuli do not activate the olfactory bulb), parosmia (some odors are interpreted as other odors), and phantosmia (hallucinations of smells that are not there). Based on this information, what specific condition is indicated in a person who mistakenly perceives the smell of peppermint as the same as the smell of something that is rotten, foul, and decomposed? A) Anosmia B) Parosmia C) Dysosmia D) Phantosmia Answer: B

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Skeletal muscle A) expands the large blood vessels. B) contracts the large blood vessels. C) propels food through the digestivetract. D) is the muscle tissue of the heart. E) moves the body. Answer: E 2) Which of these muscle components is the smallest? A) Muscle fiber B) Myofibril C) Myosin filament D) Skeletal muscle Answer: C 3) What is the function of the sarcoplasmic reticulum? A) Storage of ATP B) Contraction C) Provides support D) Storage of calcium ions Answer: D 4) Protein bands that connect sarcomeres are called A) Z discs. B) troponins. C) myofibrils. D) T tubules. Answer: A 5) The myofibrils of skeletal muscle are made up of repeating units called A) T tubules. B) fibers. C) motor units. D) sarcomeres. E) Z lines. Answer: D 6) The thick filaments of a myofibril are composed of A) sarcoplasm. B) actin. C) myosin. D) myoglobin. E) T tubules. Answer: C

Skeletal muscle appears striped because of the A) arrangement of thick and thin filaments. B) arrangement of ions across the sarcoplasmic reticulum membrane. C) way the sarcoplasmic reticulum wraps around the myofibril. D) orientation of T tubules. E) accessory proteins in thin filaments. Answer: A 8) The T tubules that tunnel deep into a muscle fiber are formed from A) neurons. B) blood proteins. C) plasma membrane. D) osteocytes. Answer: C 9) The connective tissue cords that connect muscles to bones are called A) thin filaments. B) ligaments. C) tendons. D) thick filaments. Answer: C 10) Which molecule contains a binding site for the attachment of myosin heads? A) Myoglobin B) Tropomyosin C) Actin D) Troponin Answer: C 11) How does an action potential enter a skeletal muscle cell? A) In response to the release of calcium ions B) Through a T tubule C) By diffusion D) As a result of the interaction between actin and myosin Answer: B 12) The site of communication between a neuron and a muscle fiber is called a A) sarcomere. B) Z disc. C) neuromuscular junction. D) myofibril. Answer: C 13) When lifting a heavy object, the strength of leg muscle contractions is determined by the A) frequency of action potentials and number of muscle fibers stimulated. B) number of calcium ions released by the sarcoplasmic reticulum. C) amount of ATP used by each active sarcomere during muscle contraction. D) number of thick and thin filaments involved in each sarcomere during contraction. Answer: A

14) What is the function of troponin and tropomyosin during skeletal muscle contraction? A) To remove calcium from the muscle fiber B) To regulate bonding between actin and myosin C) To generate an action potential D) To prevent over-contraction of musclefibers E) To increase the amount of calcium entering the muscle fiber Answer: B 15) Muscles used for activities that require fine motor control, such as holding and writing with a pencil, have A) motor units consisting of many muscle cells. B) access to large amounts of ATP. C) motor units consisting of only a few muscle cells. D) many neuromuscular junctions. Answer: C 16) Calcium binding to A) tropomyosin B) myosin C) troponin D) actin

initiates skeletal muscle contraction.

Answer: C 17) Which of the following is TRUE with regard to the sliding filament mechanism of muscle contraction? A) When a muscle fiber is contracting, the thin fibers are connected to the thick fibers. B) The energy for contraction comes from the breakdown of actin into myosin. C) When actin pushes the Z discs farther apart, the muscle contracts. D) The muscle relaxes when calcium ions are released into the fluid surrounding the thick and thin filaments. Answer: A 18) When a muscle fiber receives an action potential from a neuron, how many sarcomeres in the fiber contract? A) The number that contracts is inversely proportional to the strength of the action potential. B) All of the sarcomeres in the fiber contract. C) Approximately one half of the sarcomeres in the fiber contract. D) The number that contracts is directly proportional to the strength of the action potential. Answer: B 19) The term motor unit refersto A) all sarcomeres within a single muscle fiber. B) all the muscle fibers that synapse with one motor neuron. C) all the motor neurons stimulating a skeletal muscle. D) an entire skeletal muscle. E) all the skeletal muscles in one region of the body. Answer: B

20) The fluid in the sarcoplasmic reticulum contains a high concentration of the stimulation of an actionpotential. A) calcium B) potassium C) iron D) phosphorus E) sodium

ions, which are released by

Answer: A 21) A muscle fiber generates maximum contractile force when A) it has been exposed to creatine phosphate. B) some of the myofibrils contract and then relax at the same time. C) it has been stretched excessively. D) it receives repeated action potentials from a motor neuron. Answer: D 22) Skeletal muscle produces force as the "walk" along the A) ATP molecules; myofibrils B) creatine phosphate molecules; sarcomere C) myosin heads; actin D) actin heads; myosin

Answer: C 23) Thick filaments are composed primarily of A) actin; myosin B) T tubules; Z discs C) Z discs; T tubules D) myosin; actin

, whereas thin filaments consist of

Answer: D 24) In a muscle that is resistant to fatigue, such as that of a marathon runner, you would expect A) a limited (or decreased) bloodsupply. B) elevated levels of ATP. C) very few mitochondria. D) a nonstriated appearance. Answer: B 25) Where are the largest motor units in human muscles located? A) Leg muscles B) Muscles of the face C) Arm muscles D) Muscles in the hand Answer: A 26) How would a calcium deficiency affect the process of skeletal muscle contraction? A) Myosin heads would not bind to actin efficiently. B) Skeletal muscles would not be able to utilize ATP as a source of fuel. C) The myosin heads would remain attached to actin molecules. D) The action potential would be blocked from entering the muscle fiber. Answer: A

27) What would happen to a person who was poisoned with a chemical that blocks the production of neurotransmitters at neuromuscular junctions? A) The person's muscles would contract uncontrollably. B) The muscles would swell. C) The sarcoplasmic reticulum would release sodium ions instead of calcium ions. D) The muscles would be unable to contract. Answer: D 28) Fast-twitch muscle fibers, such as those that predominate in the legs of sprinters, fibers, which predominate in the legs of marathon runners. A) contain higher levels of myoglobin B) contain fewer mitochondria C) have a greater blood supply D) produce more ATP

than slow-twitch

Answer: B 29) In skeletal and cardiac muscles, relaxation occurs as reticulum. A) chloride B) sodium C) potassium D) calcium

ions are pumped back into the sarcoplasmic

Answer: D 30) In cardiac muscle A) calcium enters the cell from storage chambers called intercalated discs. B) an action potential spreads throughout the Z discs. C) potassium is released from the sarcoplasmic reticulum. D) intercalated discs connect the muscle fibers together. Answer: D 31) Both smooth and cardiac musclefibers A) are striated. B) possess intercalated discs. C) contain a single nucleus. D) have multiple nuclei. Answer: C 32)

muscle constricts arteries when blood pressure drops suddenly. A) Striated B) Smooth C) Cardiac Answer: B

33) Smooth muscle A) contracts when stretched. B) does not contain actinor myosin. C) is under voluntary control. D) produces rapid contractions. Answer: A

34) Which of the following would be composed of smooth muscle? A) Muscles of the uterus B) Muscles that allow you to cross your eyes C) Quadriceps (leg muscle) D) Ventricles of the heart Answer: A 35) Which of the following is TRUE of cardiac muscle? A) Its cells are tapered at each end. B) It is under voluntary control. C) It is not striated, like skeletal muscle. D) Its cells contain large numbers of mitochondria. Answer: D 36) Cnidarians have what type ofskeleton? A) They don't have a skeleton B) Endoskeleton C) Hydrostatic skeleton D) Exoskeleton Answer: C 37) Which of these animals is correctly matched with its type of skeleton? A) Shark/hydroskeleton B) Bird/exoskeleton C) Earthworm/endoskeleton D) Mayfly/hydroskeleton E) Lobster/exoskeleton Answer: E 38) What is the major disadvantage of an exoskeleton? A) It hardens only after an extended exposure to air. B) It must be periodically shed for growth to occur. C) It does not provide effective support for muscles. D) It does not protect the internal organs. Answer: B 39) Earthworms and slugs move by A) stretching their longitudinal muscles and contracting their circular muscles. B) alternating contractions of longitudinal and circular muscles. C) contracting their cilia. D) contracting extensor and flexor muscles attached to their endoskeleton. Answer: B 40) An exoskeleton is characteristic of A) mammals; spiders B) insects; reptiles C) sea anemones; humans D) reptiles; insects

, whereas an endoskeleton is a characteristic of

Answer: B

41) Bones store calcium and A) phosphorus. B) amino acids. C) manganese. D) glycogen. E) magnesium. Answer: A 42) If a doctor tells a patient that he has broken an axial bone, to which of these bones would the doctor be referring? A) Clavicle B) Vertebra C) Radius D) Ilium E) Fibula Answer: B 43) If an athlete damages the cartilage in her knee, it tends to heal very slowly because cartilage A) is dead tissue. B) is rejected by the body as it is formed. C) hardens with age. D) cannot be replaced or repaired by the body. E) lacks a blood supply. Answer: E 44) Cartilage primarily consists of A) glycoproteins and collagen. B) magnesium and manganese. C) myosin. D) actin. E) calcium and phosphate. Answer: A 45) The living cells of cartilage are called A) osteoblasts. B) osteocytes. C) chondrocytes. D) osteoclasts. Answer: C 46) Bone-forming cells are known as A) osteoclasts. B) osteocytes. C) osteoblasts. D) chondrocytes. Answer: C

47) The hard, outer shell of vertebrate bone A) is spongy bone. B) is compact bone. C) is made of glucosamine. D) does not contain osteons. Answer: B 48) Osteoporosis may occur when the activity of A) osteocytes; osteoclasts B) osteoclasts; osteoblasts C) osteoblasts; osteoclasts D) osteoclasts; osteocytes

exceeds theactivity of

Answer: B 49) Which of the following increases bone mass? A) Increasing the action potentials that directly stimulate bones B) Dietary nitrogen supplements C) Moderate stress from weight-bearing exercises D) Increased osteoclast activity Answer: C 50) Which of the following individuals is most likely to have the greatest bone density? A) A person who has been chronically ill and in bed B) An astronaut who has been in space for an extended time C) A computer programmer D) A person who walks 30 minutes a day Answer: D 51) A callus is a mass of bone and cartilage that A) forms after a bone breaks. B) thickens the fibrous structure of a muscle. C) is involved in bone formation in the vertebrate embryo. D) is a form of bone cancer. Answer: A 52) Osteoporosis is the A) loss of calcium from hardbone. B) conversion of cartilage to bone in the developing embryo. C) painful swelling of joints. D) detachment of a ligament from a bone. Answer: A 53) Red bone marrow, which produces red blood cells, white blood cells, and platelets, is located in A) cartilage. B) ligaments. C) compact bone. D) spongy bone. Answer: D

54) What advantage does the activity of osteoblasts and osteoclasts impart to vertebrates, even after growth has finished? A) Bone growth never finishes; it continues at a slow pace throughout life. B) The cells allow bone to get stronger as physical demands are placed on it. C) As old bones are dissolved, new bones can be formed. D) The cells enable bone to lengthen and shorten as needed. Answer: B 55) When you break your leg, a thickened area forms around the outside of the bone. Over a period of time, this thickened area A) forms new tendons, ligaments, and/or muscles. B) is digested by enzymes secreted by the muscles. C) becomes a permanent part of the spongy bone. D) moves to the skin surface and is shed as dead skin. E) is dissolved by osteoclasts as osteoblasts add new bone. Answer: E 56) It is possible to remove calcium from compact bone by soaking the bone in vinegar for an extended period of time. Once the calcium is gone, the bone should be A) more rigid and inflexible. B) about half the size as before soaking. C) extremely flexible. D) completely dissolved. Answer: C 57) What happens to an astronaut who spends 2 months in the weightless environment of a space capsule? A) Bone density decreases and muscle mass increases. B) Bone density increases and muscle mass decreases. C) Bone density increases and muscle mass increases. D) Bone density decreases and muscle mass decreases. Answer: D 58) After falling down a flight of stairs, it feels like you broke your ankle; however the emergency room doctor says you tore a ligament. This means you tore the A) the cartilage in your anklejoint. B) connective tissue band that attaches muscle to bone. C) connective tissue band that joins two bones. D) insertion of a muscle. E) delicate membrane that covers the surface of the bone. Answer: C 59) Which of the following attaches one bone to another bone at a joint? A) Callus B) Tendon C) Cartilage D) Ligament Answer: D

60) The muscles of your lower leg are arranged in antagonistic pairs so that you A) can stand upright. B) obtain a stronger contraction than you would with a single muscle. C) have a backup when one muscle is not strong enough. D) can both flex and extend your leg. Answer: D 61) The end of a skeletal muscle that is attached to a stationary, fixed bone is the origin. The end of a skeletal muscle that is attached to a movable bone is called the A) extensor. B) hinge. C) insertion. D) joint. E) flexor. Answer: C 62) In a hinge joint A) motion occurs when gravity pulls on the insertion. B) movement in three dimensions ispossible. C) an extensor muscle rotates thebones. D) the flexor and the extensor must contract at the same time. E) movement can occur only in two dimensions. Answer: E 63) What might be a major disadvantage of having a ball-and-socket joint, rather than a hinge joint, in the human knee? A) Decreased joint stability B) Reduced ability to move the lower leg C) Decreased muscle strength D) Decreased joint flexibility Answer: A 64) Cartilage is composed of specialized cells called A) erythrocytes. B) platelets. C) chondrocytes. D) osteoblasts. E) osteoclasts. Answer: C 65) Motor units are all of the sarcomeres that make up a muscle fiber. A) True B) False Answer: B 66) Action potentials stimulate the sarcoplasmic reticulum to release chloride ions into the muscle cell. A) True B) False Answer: B

67) The sternum is part of the axial skeleton. A) True B) False Answer: A 68) Cartilage is well supplied with blood vessels. A) True B) False Answer: B 69) Some joints, such as those joining the bones of the skull, are immobile and do not allow the two bones involved to move. A) True B) False Answer: A 70) At a joint, the end of a skeletal muscle that is attached to the bone that moves is known as the origin. A) True B) False Answer: B SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 71) The type of ion found in high concentrations in the sarcoplasmic reticulum is

Answer: calcium(Ca2+) 72) The vertebrate skeleton is made up of

, ligaments, and bones.

Answer: cartilage 73) During embryonic development, the skeleton is initially made of

, which is later replaced by bone.

Answer: cartilage 74) In the human skeleton, the

is a ball-and-socket joint.

Answer: shoulder, or hip 75) A joint that is movable in only two dimensions, such as the elbow, is called a

joint.

Answer: hinge 76) Arrange these muscle tissue groupings in order, from most inclusive to least inclusive: sarcomere, motor unit, thick and thin filaments, myofibril, muscle fiber. Answer: motor unit, muscle fiber, myofibril, sarcomere, thick and thin filaments 77) What are tendons? Answer: the tough connective tissue bands that attach muscles to bone 78) In light of the role of calcium ions in muscle contraction, what happens to a person who is deficient in dietary calcium? Answer: Muscle weakness occurs due to an inability to remove tropomyosin from myosin binding sites on the actin molecules. As a result, myosin cannot bind to actin molecules and the sarcomere will not shorten.

79) Describe the differences between fast-twitch and slow-twitch muscle fibers. Answer: Slow-twitch muscles fibers do not contract as fast as fast-twitch muscles; they have a lot of mitochondria, high levels of myoglobin, and a plentiful blood supply. Fast-twitch fibers twitch faster and more strongly than slow-twitch muscle fibers; they have fewer mitochondria and a smaller blood supply. 80) How does a muscle return to its extended condition after contracting? Answer: It is pulled back to the extended position by another muscle that is antagonistic to it. 81) What two types of contractions do smooth muscles perform? Answer: slow, sustained contractions and slow, wavelike contractions 82) Describe some of the important functions of the vertebrate endoskeleton. Answer: The vertebrate endoskeleton allows locomotion (joints), provides a rigid framework that supports the body and provides protection, contains red bone marrow (important in the production of blood cells and platelets), and serves as a storage depot for calcium and phosphorous. 83) Over time, what will happen to the structure of the bones of a left-handed professional baseball player? Answer: The bones associated with the left arm (and left-handed activities) will grow thicker than the bones of the right arm. 84) Describe the functions of the three types of bone cells. Answer: Osteoclasts tunnel through (or dissolve) existing bone, osteoblasts secrete the materials for making new bone and prevent bones from becoming brittle, and osteocytes coordinate the activity of osteoblasts and osteoclasts. 85) List the steps in the process by which a bone heals. Answer: A clot forms, osteoclasts eat away damaged material, osteoblasts form a callus, remodeling occurs, and osteoclasts remove excess bone. 86) Many people hope that they will one day be able to travel into space for extended periods of time. What are the health risks to the bones and muscles of those people interested in such "space vacations"? Answer: Under weightless conditions, space travelers will lose bone and muscle mass because there is no pull of gravity to strengthen the bones and muscles. To maintain bone and muscle mass, they will have to do special exercises each day. If they do not, their bones and muscles will atrophy, which could have additional negative side effects on their body physiology.

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 87) Based on thisfigure, the

inserts into the patella.

A) quadriceps B) gastrocnemius C) deltoid D) coccyx E) rectus abdominus Answer: A

88) This figure illustrates what type of joint?

A) Plane B) Suture C) Ball-and-socket D) Hinge Answer: D 89) Weightlifters, bodybuilders, and other athletes who require rapid bursts of high-energy muscle output often spend a lot of money on dietary supplements. Some supplements, such as amino acids, are used as building blocks to make more high-protein muscle cells. Other supplements increase energy or provide more endurance during workouts. For example, supplements that contain creatine (often sold as creatine diphosphate) are reputed to provide more energy. Based on this information and your knowledge of muscle physiology, would you expect creatine supplements to provide extra energy? Why or why not? A) No, because the digestive system breaks creatine (a large protein macromolecule) down before it can be used by the body. B) Yes, because creatine is used directly as a source of energy by muscle cells. C) Yes, because the creatine supplement can donate phosphate ions to regenerate ATP. D) No, because creatine is not used for energy production in the body. Answer: C

90) The anterior cruciate ligament (ACL) is one of the major knee joint ligaments in humans, and damage to this ligament is fairly common in athletes. An ACL tear is most often a sports-related injury but can also result from accidents, falls, and work-related injuries. Most sports-related ACL tears occur when a person pivots or lands from a jump. Based on this information as well as your knowledge of ligaments, which of the following occurs in an athlete who has a torn ACL? A) Rapid firing of all the neurons involved in the affected motor unit B) Instability or weakness of the knee joint C) Inability to relax the quadriceps D) Inability to contract the quadriceps Answer: B

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Which of the following is the best definition of parthenogenesis? A) The creation of new organisms from body parts that have been pinched off from the parent B) Eggs from a female developing into offspring without being fertilized C) The combining of genetic material from two parents to produce genetically different offspring D) A single organism producing both eggs and sperm and fertilizing itself E) Gametes from the male developing into new offspring without combining with an egg Answer: B 2) Brittle stars can regrow a new arm if an existing one is broken off. This is an example of A) hermaphrodism. B) regeneration. C) budding. D) sexual reproduction. E) parthenogenesis. Answer: B 3) All male honeybees develop from unfertilized eggs. This is an example of A) parthenogenesis. B) hermaphrodism. C) budding. D) external fertilization. E) sexual reproduction. Answer: A 4)

is the asexual process by which an organism grows a small version of itself on the body of the adult, which then pinches off when it is large enough to be independent. A) Parthenogenesis B) Regeneration C) Mitosis D) Fission E) Budding Answer: E

5) An animal, such as an earthworm, that is hermaphroditic A) spawns. B) reproduces by budding. C) reproduces by unfertilized eggs. D) produces both eggs and sperm. E) reproduces by regeneration. Answer: D 6) Spawning depends on A) internal fertilization. B) copulation. C) asexual reproduction. D) the synchronized release of eggs and sperm into the water. E) the release of a spermatophore into the water. Answer: D

7) The production of new phenotypes occurs with A) budding. B) sexual reproduction. C) fragmentation. D) parthenogenesis. E) regeneration. Answer: B 8) The most important function of sexual reproduction is A) keeping the genes from changing. B) producing offspring identical to theparents. C) limiting genetic recombination. D) preserving genetic purity. E) creating genetic variability. Answer: E 9) Female salmon build nests in gravel river bottoms to lay eggs, which are then fertilized by male salmon that approach and deposit their sperm over the eggs. This is an example of A) internal fertilization. B) spawning. C) parthenogenesis. D) copulation. E) hermaphrodism. Answer: B 10) Chemical signals released into the environment are called A) spermatophores. B) hormones. C) apomones. D) pheromones. E) telemones. Answer: D 11) The onset of puberty is triggered by maturation of the brain, which stimulates the hypothalamus to secrete A) progesterone. B) chorionic gonadotropin (CG). C) luteinizing hormone (LH). D) testosterone. E) gonadotropin-releasing hormone (GnRH). Answer: E 12) If a child develops an anterior pituitary tumor that reduces LH and FSH production, the child will A) produce excess testosterone or estrogen. B) not develop gonads. C) experience delayed or disrupted puberty. D) develop secondary sexual characteristics beforepuberty. E) have decreased production of GnRH. Answer: C

13) The development of secondary sexual characteristics is due to A) decreased levels of GnRH. B) decreased LH levels. C) increased levels of progesterone. D) decreased levels of estrogen or testosterone. E) increased levels of estrogen or testosterone. Answer: E 14) In men, as testosterone levels increase, LH levels A) remain the same. B) move up or down depending on the point in the cycle. C) decrease. D) increase. Answer: C 15) The only flagellated cells in the human body are A) mature ova. B) primary oocytes. C) sperm. D) primary spermatocytes. E) Sertoli cells. Answer: C 16) Gonadotropin-releasing hormone (GnRH) A) stimulates the release of FSH and LH. B) causes endometrial cells to multiply. C) is secreted when there is a high level of progesterone in the blood. D) is produced by thepituitary. E) is made by the ovaries. Answer: A 17) What is the function of an acrosome? A) It propels the sperm through the female reproductive tract. B) It protects the sperm from vaginal secretions. C) It contains a haploid nucleus. D) It contains enzymes that dissolve the protective layers around the egg. E) It holds large numbers of mitochondria. Answer: D 18) In the male, the primary target of FSH is A) seminal vesicles. B) interstitial cells. C) the prostate gland. D) Sertoli cells. E) bulbourethral glands. Answer: D

19) Which of these hormones stimulates the production of testosterone? A) LH B) Inhibin C) FSH D) Chorionic gonadotropin E) GnRH Answer: A 20) Mature sperm are stored inthe A) epididymis. B) penis. C) seminal vesicles. D) prostate gland. E) urethra. Answer: A 21) The epididymis connects the A) vas deferens and the urethra. B) vas deferens and the seminal vesicles. C) seminiferous tubules and the urethra. D) prostate and theurethra. E) testis and the vasdeferens. Answer: E 22) Which of the following is the correct path sperm travel on their way out of the male? A) Urethra → vas deferens → seminiferous tubules → epididymis B) Seminiferous tubules → vas deferens → urethra → epididymis C) Seminiferous tubules → epididymis → vas deferens → urethra D) Epididymis → urethra → vas deferens → seminiferous tubules E) Epididymis → seminiferous tubules → vas deferens → urethra Answer: C 23) What would happen to male hormone levels if the hypothalamus produced GnRH continuously? A) Only testosterone levels would be high. B) Only LH and FSH levels would be high. C) LH, FSH, and testosterone levels would be high. D) Testosterone levels would be low. E) Only LH and FSH levels would be low. Answer: C 24) Why is it necessary for the testes to be in the scrotum to function properly? A) The sperm are produced in the scrotal tissue and transferred to the testes to finish maturation. B) The testes develop from scrotaltissues. C) The scrotum elevates the temperature of the testes, which increases sperm production. D) The scrotum contains alkaline fluids to nourish the sperm. E) The scrotum keeps the testes at a cool temperature necessary for sperm production. Answer: E

25) If the prostate gland failed to add its enzyme-rich fluid to semen, the A) semen would exhibit reduced fluidity, hampering the ability of sperm to swim freely in the vagina. B) egg would be killed by the acidic vaginal secretions. C) semen would lack lubricating mucus. D) sperm would starve from lack of fructose. E) acrosome would rupture prematurely. Answer: A 26) Which of the following is the correct path sperm travel on their way to fertilize an egg? A) Cervix → uterine tube → vagina → uterus B) Uterus → uterine tube → cervix → vagina C) Uterine tube → vagina → uterus → cervix D) Vagina → cervix → uterus → uterine tube Answer: D 27) Most of the fluid in semen is produced by the A) epididymis. B) bulbourethral glands. C) prostate gland. D) testes. E) seminal vesicles. Answer: E 28) During spermatogenesis, committed spermatogonia undergo mitotic cell division, producing A) diploid secondary spermatocytes. B) diploid primary spermatocytes. C) diploid sperm. D) haploid primary spermatocytes. E) haploid secondary spermatocytes. Answer: B 29) The interstitial cells of the testes produce A) FSH. B) sperm. C) testosterone. D) LH. E) alkaline mucus. Answer: C 30) During ovulation, the mature follicle erupts, releasing the A) oogonium B) primary oocyte C) zygote D) secondary oocyte E) polar body Answer: D

, also known as the egg.

31) In the "typical" menstrual cycle, day 1 is the day A) fertilization occurs. B) the corpus luteum disintegrates. C) menstruation begins. D) ovulation occurs. E) LH levels surge. Answer: C 32) In the "typical" menstrual cycle, day 13 or 14 is when A) menstruation begins. B) progesterone levels peak. C) ovulation occurs. D) estrogen levels reach their lowestpoint. E) the corpus luteum disintegrates. Answer: C 33) Ovulation occurs due to asurge in A) testosterone B) FSH C) estrogen D) progesterone E) LH

concentrations.

Answer: E 34) A surge in the level of LH indicates that A) ovulation B) puberty C) the testosterone peak D) the progesterone peak E) menstruation

is about to occur.

Answer: A 35) In which respect do spermatogenesis and oogenesis differ? A) The number of chromosomes in gametes is different. B) The number of gametes produced is different. C) Spermatogenesis occurs in the epididymis, whereas oogenesis occurs in the ovary. D) The number of meiotic divisions is different. Answer: B 36) A polar body A) can be fertilized by asperm. B) is a structure found at one pole of a mature egg. C) is formed at the same time as a primary oocyte. D) nourishes the egg until it is fertilized. E) is a discarded set of chromosomes. Answer: E

37) The corpus luteum is located in the A) testis. B) penis. C) vagina. D) ovary. E) uterus. Answer: D 38) Menstruation occurs when there is a decrease in A) levels of estrogen and progesterone. B) endometrial thickness. C) levels of FSH and LH. D) the number of sperm present. E) the number of follicles. Answer: A 39) In humans, fertilization normally occurs in the A) vagina. B) uterus. C) uterine tube. D) fimbriae. E) ovary. Answer: C 40) When a sperm penetrates an egg cell A) the egg has to make a copy of itself before sperm and egg chromosomes merge. B) sperm and egg chromosomes mergeimmediately. C) the egg must undergo meiosis II before merging chromosomes with the sperm. D) the resulting cell is haploid. E) the egg undergoes changes that attract another sperm. Answer: C 41) After ejaculation, sperm live approximately A) 24 hours B) 2 to 4 days C) 2 weeks D) 1 week E) 1 month

in the female reproductive tract.

Answer: B 42) Why is it necessary for many sperm to be present in order for one to fertilize the egg? A) The combined motion of their flagella enables one sperm to push its way into the egg. B) A mass of sperm is necessary to gain entry into the ovary. C) A mass of sperm is necessary to open the uterine tube. D) A sperm cannot find the egg by itself. E) The combined enzymes digest a path through the corona radiata and zona pellucida. Answer: E

43) Sexually transmitted diseases caused by viruses include herpes, AIDS, and A) chlamydia. B) trichomoniasis. C) human papillomavirus (HPV). D) syphilis. E) gonorrhea. Answer: C 44) Which of the following causes most cases of cervical cancer? A) Pubic lice B) Gonorrhea C) Human papillomavirus (HPV) D) Trichomoniasis E) Chlamydia Answer: C 45) Painful and reoccurring genital blisters are characteristic of A) HPV. B) chlamydia. C) HIV. D) syphilis. E) genital herpes. Answer: E 46) Which of the following is a bacterial infection that can cause the uterine tubes to be blocked by scar tissue? A) Trichomoniasis B) Chlamydia C) HIV D) HPV E) Genital herpes Answer: B 47) Oogenesis begins A) after the sperm and eggmerge. B) at puberty. C) at around day 14 of each menstrual cycle. D) during embryonic development. E) after copulation. Answer: D 48) Vasectomy and tubal ligation resultin A) decreased levels of hormones. B) a lack of semen or menstrual flow. C) an interruption of the path taken by the egg or sperm. D) inability to produce eggs orsperm. E) atrophy of the gonads. Answer: C

49) After a vasectomy, the semen produced will not contain A) acid-neutralizing fluid. B) mucus. C) sperm. D) fructose. E) enzymes. Answer: C 50) Contraceptive methods that rely on synthetic hormones A) prevent the implantation of a fertilized egg in the uterus. B) prevent ovulation. C) destroy fertilized eggs. D) prevent the sperm and egg from meeting. E) kill sperm. Answer: B 51) Other than abstinence and sterilization, the most effective method of contraception is the A) contraceptive sponge. B) diaphragm. C) IUD. D) condom. E) birth control pill. Answer: E 52) If taken within 72 hours of unprotected intercourse, the "morning after" pill should A) reduce sperm motility. B) delay or prevent ovulation. C) encourage the formation of the corpus luteum. D) thicken the cervical mucus. E) increase progesterone secretion from the ovary. Answer: B 53) The vaginal ring A) blocks sperm from reaching theegg. B) kills sperm. C) releases hormones that prevent ovulation. D) decreases testosterone production. E) prevents STDs. Answer: C 54) Sexual reproduction produces individuals that are always genetically identical to the parents. A) True B) False Answer: B 55) The production of offspring from unfertilized eggs is called parthenogenesis. A) True B) False Answer: A

56) Spawning animals rely on mating behaviors, chemical signals, and/or environmental cues for reproduction to take place. A) True B) False Answer: A 57) Internal fertilization only occurs bycopulation. A) True B) False Answer: B 58) The epididymis functions solely to store sperm. A) True B) False Answer: B 59) Spermatids are haploid, containing only half the amount of genetic material present in the primary spermatocyte. A) True B) False Answer: A 60) FSH stimulates interstitial cells in the testes to produce testosterone. A) True B) False Answer: B 61) The presence of testosterone triggers the release of LH to produce more testosterone, as explained by negative feedback. A) True B) False Answer: B 62) A diploid primary spermatocyte divides to produce two haploid secondary spermatocytes. A) True B) False Answer: A 63) During oogenesis, oogonia differentiate and become diploid primary oocytes, which divide to produce four diploid secondary oocytes. A) True B) False Answer: B 64) Following ovulation, the levels of LH increase dramatically. A) True B) False Answer: B

65) Day 1 of the menstrual cycle is when ovulation occurs. A) True B) False Answer: B 66) In women, the combined effects of estrogen and progesterone cause a decrease in GnRH levels. A) True B) False Answer: A 67) After ovulation, the mature follicle becomes the corpus luteum. A) True B) False Answer: A 68) The increased levels of estrogen from the maturing follicle cause a decrease in GnRH levels. A) True B) False Answer: B 69) During an erection, blood pressure in the penis is decreased. A) True B) False Answer: B 70) The layer of cells that forms a barrier between the sperm and the egg is the corona radiata. A) True B) False Answer: A 71) HIV, which causes AIDS, can be cured by using broad-spectrum antibiotic therapy. A) True B) False Answer: B 72) Chlamydia is the most frequently reported bacterial sexually transmitted disease in the United States. A) True B) False Answer: A 73) Sexually transmitted infections can be spread only via unprotected intercourse. A) True B) False Answer: B 74) If a woman is attempting to become pregnant, the best time for her to have intercourse is day 21 of the "typical" menstrual cycle. A) True B) False Answer: B

75) The myometrial lining of the uterus thickens in response to increased levels of estrogen and progesterone. A) True B) False Answer: B 76) Contraceptive implants prevent ovulation by releasing progesterone. A) True B) False Answer: A 77) Barrier methods of contraception protect individuals from STDs. A) True B) False Answer: B 78) The contraceptive patch prevents pregnancy by killing sperm. A) True B) False Answer: B SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 79) Animals that have internal fertilization without copulation often package their sperm in inserted into the female.

, which are

Answer: spermatophores 80) A single organism that produces both eggs and sperm, and can self-fertilize, is a

Answer: hermaphrodite 81) During the process of

, aquatic species release large numbers of gametes into the water

Answer: spawning 82) The lower end of the uterus is nearly closed by a ring of connective tissue called the

Answer: cervix 83) The hypothalamic hormone

controls the release of LH and FSH in both males and females.

Answer: gonadotropin-releasing hormone (GnRH) 84) The

is a tube that carries sperm from the epididymis to the urethra.

Answer: vasdeferens 85) The head of a sperm consists of the

and a cap of hydrolytic enzymes called the acrosome.

Answer: nucleus 86) Sixty percent of the fluid in semen comes from the uterine contractions to help transport the sperm.

; this fluid contains prostaglandins that stimulate

Answer: seminal vesicles 87) The

provides the egg a pathway between the ovary and the uterus.

Answer: uterine tube (or oviduct or Fallopian tube) 12

88) The monthly shedding of the uterine lining is called

Answer: menstruation 89) After the mature follicle releases the egg, the remaining follicle cells form the

Answer: corpusluteum 90) During the first half of the menstrual cycle, GnRH stimulates the release of FSH, which stimulates the growth of follicle cells to secrete increasing levels of , which then stimulates the release of more GnRH, creating a positive feedback loop. Answer: estrogen 91) Around day 21 of the menstrual cycle, levels of the hormone luteum, peak.

, which is producedby the corpus

Answer: progesterone 92)

causes both genital warts and cervical cancer. Answer: HPV (human papillomavirus)

93) A is a sperm-killing chemical that is more effective as a contraceptive when used in combination with a condom or diaphragm. Answer: spermicide 94) Birth control injections use synthetic

to prevent ovulation.

Answer: progesterone 95) Vasectomy and tubal ligation are forms of

Answer: sterilization 96) A(n)

is a contraceptive device that is inserted into the uterus, where it remains for several years.

Answer: IUD (intrauterine device) 97) A

prevents sperm from entering the vagina and provides some protection against STDs.

Answer: condom 98) Explain how a parthenogenetic organism can produce diploid offspring. Answer: By doubling the number of chromosomes in the eggs, either before or after meiosis 99) Why must organisms that spawn release huge numbers of eggs and sperm? Answer: Spawning depends on releasing eggs and sperm into the environment and hoping they meet. The odds are not in favor of this meeting occurring, so large numbers of eggs and sperm are produced to increase the likelihood that somewill meet. 100) Explain the advantage that asexually reproducing animals have over those that reproduce sexually. Answer: Animals that reproduce asexually do not require a mate and so can reproduce rapidly. 101) What role do courtship behaviors play in spawning? Answer: Many spawning animals rely on courtship behaviors to signal sexual readiness.

102) What is the function of Sertoli cells? Answer: To regulate sperm production and nourish the developing sperm 103) What does the corpus luteum produce? Answer: Estrogen and progesterone 104) Why do FSH levels drop after ovulation? Answer: After ovulation, the corpus luteum begins to produce estrogen and progesterone, which inhibits GnRH production by negative feedback, reducing the release of FSH. 105) Ovulation test kits measure the level of LH. Why does this help to predict when ovulation will occur? Answer: LH levels surge just prior to ovulation. Knowing when the LH peak occurs enables one to estimate the time of ovulation. 106) What role does the corpus luteum play in maintaining the endometrium? Answer: The corpus luteum secretes estrogen and progesterone, which are both necessary to maintain the endometrium. When levels of estrogen and progesterone drop, menstruation occurs. 107) What are the three glands that contribute fluid to semen? Answer: Seminal vesicles, prostate, and bulbourethral glands 108) Is it possible for a man to be sterile and still produce semen? Explain. Answer: Yes; semen contains sperm and secretions from the seminal vesicles, prostate, and bulbourethral glands. If a man is sterile, he is not producing sperm, which is only one component of semen. 109) Why are the secretions of the seminal vesicles, prostate glands, and bulbourethral glands necessary for successful reproduction? Answer: They activate swimming by the sperm, provide energy to the sperm, and neutralize the acids of the vagina. 110) What external layers must a sperm penetrate in order to fertilize the egg? Answer: The corona radiata and the zona pellucida 111) Some STDs cause infertility. How? Answer: STDs can cause infertility by producing scar tissue in the vas deferens and uterine tubes. Two examples are gonorrhea and chlamydia. 112) Why are STDs so easily spread? Answer: Many STDs are asymptomatic and may be transmitted between unsuspecting sexual partners. 113) How do barrier methods of birth control prevent conception? Answer: Barriers prevent the egg and sperm from meeting, so fertilization cannot occur. 114) How do hormonal methods prevent conception? Answer: They disrupt the normal hormonal cycle, so ovulation should not occur.

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

115) The structure labeled 1 containsa A) primary spermatocyte. B) spermatogonium. C) primary oocyte. D) secondary spermatocyte. E) secondary oocyte. Answer: C 116) The structure labeled 6 secretes A) FSH. B) GnRH. C) estrogen and progesterone. D) testosterone and estrogen. E) LH. Answer: C 117) The increase in size of structure 2 is regulatedby A) FSH. B) testosterone. C) GnRH. D) inhibin. E) progesterone. Answer: A

118) Sea stars prey on clams. Clam fishermen used to cut up sea stars and throw the parts back into the ocean in order to protect the clam beds they fished. Within months, the beds were crawling with even more sea stars, and there were almost no clams. Why, in hindsight, was cutting up the sea stars not such a good idea? A) Cutting up sea stars stimulates spawning of sea stars in the immediate vicinity. B) This allowed the sea stars to reproduce parthenogenetically. C) This allowed sea stars to spawn more easily. D) Sea stars have the ability to regenerate new individuals from body parts. E) Sea stars do not eat clams. Answer: D 119) To take advantage of ecotourism, a resort is built near a coral reef so that tourists can observe the spawning that occurs shortly after a full moon. As an added benefit, several species of colorful fishes are attracted to the area. Tour boats go out nightly and shine large spotlights to attract the fish. Tourists are enchanted by the display of fishes but have begun to question why spawning among the corals has ceased. What is the probable cause for the lack of spawning? A) The tourists are too loud. B) Corals time their spawning by the phase of the moon; spotlights mimic the full moon, so spawning can't occur. C) The fish are releasing chemical signals that interfere with spawning among the corals. D) The fish are eating the spawn. E) The spotlights are causing the corals to spawn during the day rather than at night. Answer: B 120) A couple has been trying unsuccessfully to conceive for several years. An examination reveals that scar tissue blocks the woman's uterine tubes. The woman has complained about large amounts of vaginal discharge, which coincide with her husband complaining of painful urination and a pus-filled discharge from his penis. Antibiotics clear up the infections. This couple has probably been infected with A) pubic lice. B) HPV. C) herpes. D) gonorrhea. E) a protist. Answer: D

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) One characteristic of animal development is the specialization in both structure and function that cells undergo. This is called A) differentiation. B) direct development. C) indirect development. D) placental development. E) internal development. Answer: A 2) What is differentiation? A) The process in which different organs specialize in function B) The process in which different tissues specialize into specific organs C) The process in which different organ systems become specialized D) The process in which different cells develop into different cell types Answer: D 3) Early animal embryos are composed of stem cells, unspecialized cells that are capable of dividing and renewing themselves for long periods. If a stem cell divides by mitosis so that one cell eventually becomes part of the brain and the other cell becomes part of a salivary gland, the cells have A) diffused. B) lost genes. C) differentiated. D) increased their genetic variability. E) taken up genes from surrounding cells. Answer: C 4) When a researcher transplanted the nucleus of an intestinal cell from a tadpole into an egg cell whose nucleus had been destroyed, the egg developed into a normal frog. This illustrates that A) genes are gained during the process of differentiation. B) each cell of an organism has all the genes needed for development. C) the homeobox genes in a transplanted nucleus undergo mutation. D) a nucleus that is removed from its normal location is influenced by adjoining cells. E) scientists can clone a human by putting one of his or her nuclei into an egg cell. Answer: B 5) The metamorphosis of a caterpillar into a butterfly is an example of A) internal development. B) direct development. C) placental development. D) external development. E) indirect development. Answer: E 6) Birds hatch out of their eggs looking like small versions of the adult. This is an example of A) direct development. B) genetic dwarfism. C) internal development. D) external development. E) indirect development. Answer: A

7) Human embryos differ from bird embryos in that A) human embryos have a yolk sac, but it contains very little yolk. B) bird embryos undergo metamorphosis to become sexually mature adults. C) bird embryos have an extra membrane, the allantois, that is not found in human embryos. D) human embryos have no yolksac. E) human embryos do not undergo cleavage. Answer: A 8) The embryo of a A) butterfly B) lobster C) dragonfly D) snake E) frog

undergoes direct development.

Answer: D 9) During the embryonic stage, a hollow ball of cells is known as a A) blastula. B) larva. C) chorion. D) gastrula. E) morula. Answer: A 10) As a morula, the embryo consists of A) a hollow ball of cells. B) a cluster of cells that are much larger than normal cells. C) three differentiated layers of cells. D) cells that have different DNAcontent. E) a solid mass of cells, each the size of the zygote. Answer: B 11) The nervous system forms fromthe A) ectoderm. B) endoderm. C) chorion. D) yolk. E) mesoderm. Answer: A 12) The cells that line the inside of the blastopore become the A) digestive tract. B) nervous system. C) skeleton. D) skin. E) muscles. Answer: A

13) Which of the following is the result of gastrulation? A) A three-layered embryo B) A hollow ball of cells C) A blastula D) A zygote E) The formation of organs Answer: A 14)

is the developmental event that results in the formation of a primitive gut and the three tissue layers. A) Blastulation B) Metamorphosis C) Induction D) Cleavage E) Gastrulation Answer: E

15) Which germ layer forms thepancreas? A) Mesoderm B) Endoderm C) Endodermis D) Ectoderm E) Epidermis Answer: B 16) Which extraembryonic membrane lies immediately beneath the shell of a reptile embryo? A) Chorion B) Yolk sac C) Placenta D) Allantois E) Amnion Answer: A 17) In a reptile egg, which membrane is analogous to a lung? A) Blastocyst B) Chorion C) Amnion D) Yolk sac E) Allantois Answer: B 18) In placental organisms, the placenta. A) chorion B) amnion C) allantois D) yolk sac E) blastopore

of the embryo merges with the endometrial lining of the uterus to form the

Answer: A

19) In a bird egg, the A) chorion B) amnion C) allantois D) blastocyst E) yolk sac

provides the watery environment in which the embryo develops.

Answer: B 20) If the formation of the endoderm does not take place in an embryo, yet the embryo, for whatever reason, continues to develop, which of the following structures will NOT develop? A) Skin B) Heart C) Kidneys D) Nervous system E) Stomach Answer: E 21) During mammalian development, a A) morula becomes a blastula. B) blastula becomes a zygote. C) morula becomes gastrula. D) zygote becomes a blastula. E) gastrula becomes amorula. Answer: A 22) Your biceps muscle is derived from the A) ectoderm. B) blastopore. C) amnion. D) mesoderm. E) endoderm. Answer: D 23) What makes the cells of a developing embryo differentiate into various types of cells? A) Special genes in the cytoplasm cause this differentiation. B) Different genes are activated. C) Once certain genes of a cell have caused it to differentiate, the other genes are lost. D) The DNA of their mitochondria is different. E) Theyhave different genes. Answer: B 24) In the 1920s, two German embryologists, Hans Spemann and Hilde Mangold, demonstrated that a small patch of cells, called the dorsal lip of the blastopore, would A) induce the surrounding cells todifferentiate. B) form the chorion. C) become the digestive tract. D) become the neural tube. E) lack the genes necessary to develop the embryo. Answer: A

25) After induction occurs, the A) transcription of all genes stops. B) cells have different genes. C) fate of each cell is permanently fixed. D) DNA of the mitochondria differentiates into new genes. Answer: C 26) Transplanting embryonic eye tissue into the back of a developing tadpole will cause a lens to grow on the back of the tadpole. This is an example of A) gastrulation. B) metamorphosis. C) cleavage. D) induction. E) programmed cell death. Answer: D 27) Induction refers to A) chemical messengers from one embryonic cell influencing the development of other cells. B) the migration of cells to form the gastrula. C) the formation of the mesoderm layer in a gastrula. D) the formation of the nervous system. E) hormones from the mother's blood altering the development of the embryo. Answer: A 28) Cells differentiate during development because A) in each cell only some of the genes are expressed. B) chemicals in the sperm cytoplasm determine which cells develop. C) genes respond only to influences outside the mother's body. D) each cell contains only a portion of the genes. Answer: A 29) The proteins that bind to the DNA near regions where gene transcription begins are called A) transcription factors. B) the gray crescent. C) mRNA. D) homeobox genes. E) promoter genes. Answer: A 30) Based on experiments with amphibian embryos, Spemann and Mangold found that A) transplanted cells completely undifferentiated into random masses of tissue. B) transplanted cells always died. C) transplanted cells always formed a whole new embryo. D) in most cases, transplanted donor cells assumed the developmental fate of the area to which they were transplanted in the host. E) donor cells maintained their original differentiation no matter where in the host they were transplanted. Answer: D

31) A human embryo is known as a fetus after A) 4 B) 16 C) 12 D) 8 E) 2

weeks.

Answer: D 32) A developing human is considered an embryo after A) 2 B) 4 C) 8 D) 16 E) 12

weeks.

Answer: A 33) What will occur if a morula divides into three masses of cells? A) Three distinctly different embryos will develop, depending on which homeoboxes went with which mass of cells. B) Normal identical triplets will be born. C) The resulting embryos will develop severe birth defects due to missing genes. D) The resulting embryos will develop, but they may be missing some organs based on which germ layers were transferred with each section. E) The resulting embryos will die. Answer: B 34) In humans, fertilization occurs inthe A) ovary. B) vagina. C) uterus. D) uterine tube. E) testes. Answer: D 35) In humans, implantation occurs A) immediately afterfertilization. B) when the embryo is agastrula. C) after the formation of the neural tube. D) just prior to fertilization. E) when the zygote is a blastocyst. Answer: E 36) The birth defect spina bifida results in part of the spinal cord lying outside of the body. This defect is due to abnormal development of the A) embryonic disk. B) gill grooves. C) placenta. D) allantois. E) neural tube. Answer: E

37) The structure produced by cleavage of a human zygote is called a(n) A) gastrula. B) blastopore. C) blastocyst. D) chorion. E) embryonic disk. Answer: C 38) At what stage does a human embryo implant in the uterus? A) Embryonic disk B) Gastrula C) Fetal D) Blastocyst E) Morula Answer: D 39) The umbilical cord of a mammal connects the A) amnion and the chorion. B) embryo and the amnion. C) maternal and fetal bloodstreams. D) yolk sac and the allantois. E) fetus and the placenta. Answer: E 40) At which stage is the human embryo most susceptible to toxic substances? A) During organogenesis B) During cleavage C) Just beforebirth D) During the fourth and fifthmonths E) During the last trimester Answer: A 41) Suppose a pregnant woman took a drug that causes incomplete brain formation during fetal development. When must the woman have taken the drug for this effect to occur? A) In the first month ofdevelopment B) Between the second and third months of development C) Between the seventh and eighth months of development D) During labor E) Between the fifth and sixth months of development Answer: A 42) A human embryologist examines a 3-week-old embryo and notices that it has not developed a notochord. If the embryo survives, it will lack A) a brain and a spinalcord. B) a stomach and a pancreas. C) a heart and lungs. D) skin and blood vessels. Answer: A

43) The outer cell layer of the blastocyst becomes the A) yolk sac B) embryonic disk C) chorion D) inner cell mass E) primitive streak

, which forms the embryonic portion of the placenta.

Answer: C 44) Which of the following occurs in the placenta? A) All substances in maternal blood that may be harmful to the fetus are prevented from moving across the walls of the villi. B) Hormones are absorbed to prevent them from influencing the developing fetus. C) Eroding blood vessels in the endometrium bathe chorionic villi in pools of maternal blood. D) The amnion and the chorion grow into the endometrium. E) Fetal blood and maternal blood mix. Answer: C 45)

diffuse(s) from fetal blood to maternal blood in the placenta. A) Nutrients B) Infectious organisms C) Alcohol D) Wastes E) Oxygen Answer: D

46) The placental blood vessels A) allow for the exchange of wastes and nutrients but keep the maternal and fetal circulations separate. B) mix maternal blood and fetalblood. C) prevent all microbes and toxins from crossing from mother to child. D) manufacture hormones that slow the growth of the embryo, preventing it from outgrowing the uterus. E) draw oxygen from the fetal blood and pass it to the mother. Answer: A 47) As early as the respond to stimuli. A) third B) fifth C) second D) fourth E) sixth

month, as the brain and spinal cord grow, the fetus can demonstrate movement and

Answer: A 48) Most fetuses can survive outside the womb after a minimum of A) 20 B) 45 C) 38 D) 32 E) 15 Answer: D

weeks.

49) The last 7 months of pregnancy are devoted to A) formation of tissue layers. B) growth. C) formation of major organs. D) organization of organs into organsystems. E) formation of the brain. Answer: B 50) Stem cells developed by inserting genes that regulate the transcription of specific genes into cells from an adult are cells. A) induced pluripotent stem B) embryonic stem C) gastrula D) chorionic villi E) embryonic disk Answer: A 51) Most microbes cannot gain access to the fetus. However, , which causes syphilis in adults, can cross the placenta and attack the fetus, causing stillbirths and mental retardation. A) rubella B) Listeria C) Treponema pallidum D) HIV E) Staphylococcus Answer: C 52)

is the medication given to combat morning sickness that caused deformed and missing limbs in infants in the late 1950s and early 1960s. A) Alcohol B) Rubella C) Nicotine D) Accutane® E) Thalidomide Answer: E

53) Which of these hormones stimulates the production of milk? A) Estrogen B) Oxytocin C) Progesterone D) Colostrum E) Prolactin Answer: E 54) Prior to birth, stretching of the cervix by the baby's head stimulates the release of A) colostrum. B) oxytocin. C) prolactin. D) progesterone. E) estrogen. Answer: B

55) The cells of an aging animal function less efficientlybecause A) protein synthesis ceases. B) cells can no longer mitoticallydivide. C) cell metabolism is slower. D) damaged DNA cannot be repaired. E) organelles and cellular components decline. Answer: D 56) All cells in an animal, with the exception of gametes, are genetically identical. A) True B) False Answer: A 57) In animals that undergo indirect development, the newborn has a similar body structure to that of the adult. A) True B) False Answer: B 58) In indirect development, the embryo hatches into a sexually immature stage called a larva. A) True B) False Answer: A 59) The process through which a human embryo develops into an adult is called metamorphosis. A) True B) False Answer: B 60) In species with direct development, fewer offspring are produced, but a higher proportion survives to adulthood. A) True B) False Answer: A 61) The small, hollow ball of cells in early development is the zygote. A) True B) False Answer: B 62) Mitotic cell divisions of the zygote are collectivelycalled cleavage. A) True B) False Answer: A 63) A morula is a solid ball of undifferentiated cells. A) True B) False Answer: A

64) The blastopore forms during gastrulation. A) True B) False Answer: A 65) The nervous system develops from the endoderm. A) True B) False Answer: B 66) The mesoderm develops into the dermis of the skin and the skeleton. A) True B) False Answer: A 67) The amnion forms the watery environment that encloses the embryo. A) True B) False Answer: A 68) Amphibians, reptiles, and mammals pass through embryonic stages in which they have tails and webbed fingers and toes. A) True B) False Answer: A 69) Yolk sacs are found only in animals with shelled eggs. A) True B) False Answer: B 70) Homeobox genes determine the overall shape of the body and the location of its parts. A) True B) False Answer: A 71) Cellular differentiation depends on which genes are turned on or expressed in the cell. A) True B) False Answer: A 72) In blastulas, if cells from an area that would normally become skin are transplanted into an area that would become the nervous system, the transplanted cells will form structures of the nervous system. A) True B) False Answer: A

73) The developing fetus secretes chorionic gonadotropin only during the first 2 weeks of pregnancy. A) True B) False Answer: B 74) The blastocyst implants in the endometrium about 7 days after fertilization. A) True B) False Answer: A 75) At 10 weeks, the blastocyst becomes an embryo. A) True B) False Answer: B 76) The most rapid differentiation in an embryo occurs during the first 2 months of pregnancy. A) True B) False Answer: A 77) The extraembryonic membrane that sends blood vessels into the endometrium is the chorion. A) True B) False Answer: A 78) Maternal blood and fetal blood are mixed in the placenta. A) True B) False Answer: B 79) The placenta prevents pathogenic microbes such as HIV and chemicals such as alcohol from reaching the baby's bloodstream. A) True B) False Answer: B 80) Longevity in animals appears to be most related to their cells' ability to repair damage to their own DNA. A) True B) False Answer: A SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 81) During development, some cells

, or specialize in both structure and function.

Answer: differentiate 82) The process by which an organism proceeds from fertilized egg through adulthood is Answer: development

83) The eggs of many reptiles contain

, which serves as a food source for the embryo.

Answer: yolk 84) A

is the sexually immature feeding stage of an animal that undergoes indirect development.

Answer: larva 85) Newborn animals that closely resemble the adults of their species undergo

development.

Answer: direct 86) A

is a fertilized egg.

Answer: zygote 87) The process by which the three embryonic tissue layers form is called

Answer: gastrulation 88) The muscle and bone tissues of adults are derived from the embryonic tissue layer called the

Answer: mesoderm 89) The developmental fate of each cell is determined by chemical interactions among cells in a process called . Answer: induction 90)

genes code for transcription factors that regulate the transcription of other genes. Answer: Homeobox

91) Recent studies have shown that cells of the dorsal lip of the blastopore contain active for proteins that are able to induce the development of other cells.

genes that code

Answer: homeobox 92) Proteins called

bind to the DNA near the promoter regions where gene transcription begins.

Answer: transcriptionfactors 93) If a cell lacks transcription factors,

will never be transcribed.

Answer: mRNAs 94) The

implants in the mammalian uterus.

Answer: blastocyst 95) The

are finger-like extensions from the fetal membranes that extend into the endometrium.

Answer: chorionicvilli 96)

is caused when a woman drinks heavily throughout her pregnancy. Answer: Fetal alcohol syndrome

97) The mother's part of the placenta is derived from the Answer: endometrium 98) The

is the baby's contribution to the placenta.

Answer: chorion 13

99) Labor and delivery are an example of a

feedback loop.

Answer: positive 100)

is the antibody-rich milk produced in the first few days after delivery. Answer: Colostrum

101) The hormone

promotes both mammary gland development and milk production.

Answer: prolactin 102) Why do organisms that have indirect development produce hundreds of offspring, whereas those with direct development produce relatively few offspring? Answer: Organisms that have direct development provide more maternal support in both time and nutrients. Organisms with indirect development provide little, if any, parental support and very few nutrients. With the small parental investment, organisms that have indirect development spread their resources across many, many more offspring. 103) In what ways are the juveniles of direct-development species like their parents, and in what way are they different? Answer: The juveniles look like their parents and have similar nutritional needs, but they are sexually immature. 104) How does direct development of an embryo differ from indirect development? Answer: In direct development, the embryo develops to the point of resembling a small adult. In indirect development, the early forms of the organism do not look like the adult form and must go through a metamorphosis to become an adult. 105) What is a gastrula? Answer: An embryo that has developed three tissue layers 106) What occurs during organogenesis? Answer: Organs develop from the three embryonic tissue layers. 107) An embryo was exposed to a chemical early in its development. At birth, there is chromosomal damage to the skin linked to the chemical exposure. What other organ system should be examined for the same type of damage? Answer: The nervous system, since the ectoderm develops into both the skin and the nervous system. 108) An embryo was exposed to a chemical early in its development. At birth, there is chromosomal damage to the circulatory system linked to the chemical exposure. What other organ systems should be examined for the same type of damage? Answer: The muscular and circulatory systems, since mesoderm gives rise to all three systems. 109) A human embryo has webbed fingers. Why are human babies not usually born with webbed fingers? Answer: During development, programmed cell death removes the tissues between the fingers. 110) How do undifferentiated cells "know" what to become? Answer: Interactions among neighboring cells, homeoboxes, and induction affect the transcriptions of specific genes within a cell and determine which genes get transcribed and what the cell will become.

111) Adult stem cells derived from fat cells have been used to develop muscle and nerve cells in the lab. How is this possible? Answer: Because all cells contain all the genes, it is only a matter of deactivating the "fat" genes and activating the "muscle" or "nerve" genes. 112) A recent series of TV commercials promoted the idea that a woman who wants to have a healthy baby must begin to eat well and avoid some medications and alcohol before she knows she is pregnant. Why? Answer: Gastrulation and differentiation of embryonic cells occur before most women have missed their first period, when many don't even know they are pregnant yet. At these earliest stages, when important organ systems are being laid down, the embryo is very sensitive to drugs and nutrient levels. 113) Why should a woman who plans to become pregnant notify her health care provider of any medications she is taking? Answer: Many medications can damage a developing embryo or create high-risk pregnancies. 114) How is blood flow in the placenta maintained so that there is maximum opportunity for the exchange of materials while still keeping the blood of the mother and the baby separate? Answer: The mother's capillaries break down so that the chorionic villi are bathed in the mother's blood to allow maximum exposure, but the baby's blood remains in capillaries inside the chorionic villi to maintain separation. 115) If your roommate smokes and she gets pregnant, what dangers would you warn her about? Answer: Smoking during pregnancy leads to miscarriages, low birth weight, infant mortality, and possibly retardation, both social and mental. 116) German measles is a very mild infection, so why is vaccination against German measles required by most colleges? Answer: Although German measles is mild in most people, an embryo, especially in the first trimester, is very sensitive to the virus. In the embryo, German measles may cause severe birth defects. Vaccination of college students is required so that the population most likely to be having children in the next few years is protected.

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

117) The structure labeled 2 isthe A) amnion. B) embryo. C) yolk sac. D) allantois. E) chorion. Answer: A 118) The function of structure 1 is to A) store metabolic wastes. B) enclose the embryo in a liquid environment. C) provide nutrients to the embryo before implantation. D) exchange nutrients and wastes between mother and embryo. E) form the maternal component of the placenta. Answer: D 119) Blood cells form from structure A) 1. B) 2. C) 3. D) 4. E) 5. Answer: E

120) The fluid the embryo floats in is produced by structure A) 1. B) 2. C) 3. D) 4. E) 5. Answer: B 121) Metabolic wastes may be stored within structure 4, the A) allantois. B) amnion. C) embryo. D) yolk sac. E) chorion. Answer: A 122) A mad scientist decides to start combining embryos and see what develops. He takes cells from the blastula of a frog with blue skin and transplants them into the blastula of a yellow-skinned frog. The embryo receiving the cells develops blue cells in its brain and spinal cord. The scientist must have transplanted the cells into the of the recipient embryo. A) endoderm B) mesoderm C) allantois D) ectoderm E) yolk sac Answer: D

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Which of the following is a common function of stems but NOT of roots? A) Absorption B) Storage C) Anchorage D) Support Answer: D 2) You discover a plant that has unusual fruit around the seed and leaves with parallel veins. In which of the two major groups of flowering plants does it belong, and why? A) Dicots, because it has fruit around the seed B) Neither monocot nor dicot, because it has fruits C) Either monocot or dicot, depending on the presence or absence of flowers D) Monocots, because it has parallel veins Answer: D 3) All of the following are major functions of roots EXCEPT A) producing hormones. B) interacting with soil fungi. C) carrying out photosynthesis. D) storing excess sugars. E) transporting water and minerals. Answer: C 4) Which of the following characteristics helps differentiate between a monocot and a dicot? A) Presence or absence of pollengrains B) Number of flower parts C) Seeds covered by a fruit D) Presence or absence of an apical meristem E) Presence of vascular tissue Answer: B 5) Increases in plant length (such as overall height or branch and root length) result from cell division that occurs A) only in apical meristems at shoot and root tips. B) only from lateral meristems. C) equally throughout the plant body. D) from cell division of differentiated cells. Answer: A 6) As a 7-year-old child, you helped your father nail a birdhouse 7 feet high on a 10-foot-tall maple tree. If the tree grew an average of 12 inches per year, except during a dry year when it grew only 2 inches, how high in the tree is the birdhouse when you are 18 years old? A) 17 feet, 2 inches B) 19 feet C) 10 feet D) 7 feet E) 17 feet Answer: D

7) Plant cells that are actively dividing are A) meristem B) ground C) vascular D) conducting E) differentiated

cells.

Answer: A 8) What would you expect to be missing in a plant that exhibits primary growth but not secondary growth? A) Vascular tissue B) An elongated stem C) Flowers D) Thick woody branches E) An expanded root system Answer: D 9) What type of cell activity occurs in the meristem regions of plants? A) Photosynthesis B) Increased water uptake of cells C) Mitosis D) Storage of sugar E) Secondary growth Answer: C 10) What cell type permits the continued growth of a plant throughout its life? A) Differentiated cells B) Secondary cells C) Ground tissue cells D) Mesophyll cells E) Meristem cells Answer: E 11) Where are apical meristems located? A) In cylinders along the side of the root B) Between the xylem and thephloem C) At the tips of roots, shoots, and branches D) Scattered throughout the plant E) In clusters in theparenchyma Answer: C 12) Most flowering plants grow throughout their lives. This type of growth is known as A) exponential growth. B) indeterminate growth. C) secondary growth. D) primary growth. E) determinate growth. Answer: B

13) You have been asked by your instructor to go to the greenhouse and select a plant that exhibits secondary growth. Which of the following plants would you choose? A) Strawberry B) Pansy C) Rose bush D) Daffodil E) Bermuda grass Answer: C 14)

cells that convert sugar to starch in mature roots are part of the A) Companion; ground B) Phloem; vascular C) Xylem; vascular D) Periderm; dermal E) Parenchyma; ground Answer: E

15) Which of these tissue types is (are) found throughout young plant bodies? A) Epidermis only B) Epidermis and periderm C) Periderm only D) Epidermis, xylem, and phloem E) Xylem and phloem Answer: D 16) You are NOT likely to find a nucleus in A) cells of a carrot root. B) parenchyma cells. C) companion cells. D) sclerenchyma cells. E) collenchyma cells. Answer: D 17) Water-conducting cells that have a small diameter and tapered ends are called A) collenchyma cells. B) sieve-tube elements. C) vessel elements. D) tracheids. E) companion cells. Answer: D 18) The dermal tissue system consists of A) epidermis. B) phloem. C) xylem. D) collenchyma tissue. E) parenchyma tissue. Answer: A

tissue system.

19) Cells that are alive, have thickened cell walls, and support the plant body are A) sclerenchyma cells. B) parenchyma cells. C) tracheids. D) vessel elements. E) collenchyma cells. Answer: E 20) You are examining a rigid plant tissue; it does not flex or bend. Tests show that it is not consuming oxygen gas, as would be expected if aerobic respiration were occurring. This tissue is probably A) phloem. B) epidermis. C) collenchyma. D) parenchyma. E) sclerenchyma. Answer: E 21) Periderm consists of mostly A) cork cells. B) lateral meristem. C) endodermis. D) epidermis. E) undifferentiated cells. Answer: A 22) Of the major tissue systems associated with land plants, the the primary plant. A) dermal B) meristem C) parenchyma D) vascular E) ground

tissue system covers the outer surface of

Answer: A 23) Most of the interior of a leaf consists of soft, thin-walled, living A) collenchyma B) sclerenchyma C) epidermal D) guard E) parenchyma Answer: E 24) Parenchyma tissue is a component of the A) vascular B) phloem C) dermal D) ground E) epidermal

tissue system.

Answer: D

cells.

25) Which of these tissue types makes up most of the ground tissue system? A) Collenchyma B) Parenchyma C) Xylem D) Periderm E) Sclerenchyma Answer: B 26) Which of the following is NOT true of sclerenchyma tissue? A) It provides support to strengthen the plant. B) It dies at maturity. C) It is a storage site for sugars and starches. D) It is made up of cells with thickened cell walls. E) It is associated with xylem and phloem in the vascular tissue system. Answer: C 27) The formation of sieve plates between phloem sieve-tube elements allows A) adjacent cells to connect via membrane-lined pores. B) water to transpire from eachsurface. C) each cell to function independently. D) mesophyll cells to connect with xylem cells. E) the dead phloem cells to form an empty tube. Answer: A 28) Which of these plant cells is alive but has no nucleus? A) Companion cell B) Vessel element C) Collenchyma cell D) Sieve-tube element E) Parenchyma cell Answer: D 29) In vascular plants, sugar solutions and hormones are transported through tubes constructed of cells called A) plasmodesmata. B) companion cells. C) tracheids. D) sieve-tube elements. E) vessels elements. Answer: D 30) All the following are true of companion cells EXCEPT that they A) are connected to sieve-tube elements via plasmodesmata. B) cooperate with sieve-tube elements in conducting sugar-rich solutions. C) provide proteins and ATP to sieve-tube elements. D) supply materials to repair the plasma membrane of sieve-tube elements. E) fuse together to form the sieve plates of sieve-tube elements. Answer: E

31) What type of tissue transports sugars (the product of photosynthesis) throughout the plant? A) Parenchyma B) Phloem C) Xylem D) Collenchyma E) Endodermis Answer: B 32) Which of the following statements is incorrect with regard to xylem tissue? A) Water and minerals are transported by xylem. B) Companion cells provide nutrition fortracheids. C) Vessel elements contain pits. D) Xylem cells are dead at maturity. E) Xylem is composed of tracheids and vessel elements. Answer: B 33) Which of the following would you be unable to locate in xylem tissue? A) Vessel elements B) Sieve tube elements C) Cell walls with porous dimples called pits D) Sclerenchyma cells E) Tracheids Answer: B 34) Most conifers have only tracheids. Which structural feature allows water and minerals to pass from one tracheid to the next? A) Secondary cell walls B) Stomata C) Plasmodesmata D) Pits E) Sieve plates Answer: D 35) Because most of the trunk of a tree is made of xylem, it is safe to say that most of the tissue in a tree is A) conducting sugars. B) used for storage. C) dividing rapidly. D) dead. E) manufacturing sugars. Answer: D 36) An onion bulb is madeup of A) branches B) flowers C) roots D) leaves E) stems

that are specially adapted for food and water storage.

Answer: D

37) How does carbon dioxide enter a leaf? A) CO2 diffuses through the epidermis into the mesophyll. B) Atmospheric pressure forces CO2 through pits on the leaf surface. C) Dissolved CO2 is transported from roots to leaves in the xylem. D) CO2 passes through openings called stomata on the leaf surface. E) CO2 is moved by active transport into the leaf by special cells called guard cells. Answer: D 38) In the stems of plants, where is sugar converted to starch and stored as a food reserve? A) Parenchyma cells in both the cortex and pith B) Mesophyll layer C) Sclerenchyma D) Central vascular cylinder E) Collenchyma associated with xylem cells Answer: A 39) Parenchyma cells are located in all of the following structures EXCEPT the A) vascular tissues. B) cuticle. C) cortex. D) mesophyll. E) pith. Answer: B 40) In a dicotstem, the A) phloem B) xylem C) apical meristem D) pith E) cork

is between the vascular cambium and the cork cambium.

Answer: A 41) You discovered an unidentified weed and cut it almost to the ground with the lawn mower. Soon it grows as tall as it was before you cut it. This growth is likely due to which growth region? A) Lateral bud meristem B) Shoot apicalmeristem C) Vascular cambium D) Root apical meristem E) Cork cambium Answer: A 42) Which of the following is the correct order of the tissues in a young dicot stem, from the center of the stem outward? A) Cortex → vascular cambium → xylem → phloem → epidermis → pith B) Pith → phloem → cortex → xylem → vascular cambium → epidermis C) Cortex → xylem → vascular cambium → phloem → pith → epidermis D) Pith → cortex → phloem → xylem → vascular cambium → epidermis E) Pith → xylem → vascular cambium → phloem → cortex → epidermis Answer: E

43) Which of these tissues is between the epidermis and a vascular bundle in a young dicot stem? A) Phloem B) Xylem C) Cork D) Cortex E) Pith Answer: D 44) As an oak tree ages, the trunk becomes thicker and woodier due to A) tertiary B) apical meristem C) determinate D) secondary E) primary

growth.

Answer: D 45) Examination of a woody stem reveals that some tissues are dead at maturity. These dead tissues are A) sapwood and bark. B) vascular cambium and primary phloem. C) cork and heartwood. D) secondary xylem and secondary phloem. E) primary phloem and periderm. Answer: C 46) If a beaver eats the bark all the way around a tree trunk (a process called "girdling"), why does the tree die? A) Water and minerals are no longer supplied to the leaves. B) The tree cannot continue to photosynthesize. C) The phloem is damaged, and the transport of sugars ceases. D) The tree is susceptible to insect and fungal diseases. E) Cells of the lateral meristem can no longer divide. Answer: C 47) If a tree's heartwood rots out, the tree will A) replace the heartwood with sapwood to compensate for the damaged tissue. B) not survive because the active xylem is destroyed. C) be weaker than normal and more likely to blow over in a storm. D) not survive because the active phloem is destroyed. Answer: C 48) Which of the following makes up most of an old tree trunk? A) Primary phloem B) Secondary phloem C) Secondary xylem D) Vascular cambium E) Primary xylem Answer: C

49) Most of a carrot, which is adapted for carbohydrate storage, is A) cortex. B) endodermis. C) pericycle. D) xylem. E) phloem. Answer: A 50) Root hairs develop from the A) cortex. B) pericycle. C) Casparian strip. D) epidermis. E) endodermis. Answer: D 51) The location of the pericycle is best described as A) the outermost layer of the root vascular cylinder. B) a band wrapped around cells of the endodermis. C) between layers of primary xylem and primary phloem. D) adjacent to the shoot apicalmeristem. E) just beneath the epidermis. Answer: A 52) Under the influence of hormones, branch roots emerge from the A) Casparian strip B) epidermis C) central cylinder D) pericycle E) endodermis

of a growing root.

Answer: D 53) Many root epidermal cells grow projections called absorption of water and minerals. A) root hairs B) rhizomes C) villi D) rhizoids E) cilia

, which extend from their surface and help in the

Answer: A 54) On the tip of the root, the apical meristem forms the away as it pushes through the soil. A) root cap B) epidermis C) pericycle D) cortex E) endodermis Answer: A

, which prevents the meristem from being worn

55) Which of these pathways best summarizes the route of a mineral that is absorbed by a plant? A) Root hairs → endodermis → cortex → pericycle → xylem B) Root hairs → cortex → epidermis → phloem → xylem C) Root hairs → epidermis → endodermis → cortex → xylem D) Root hairs → epidermis → cortex → endodermis → pericycle → xylem E) Root hairs → pericycle → endodermis → endodermis → cortex → xylem Answer: D 56) Water and minerals are mainly absorbed from the soil through the A) root hairs. B) apical meristem. C) pericycle. D) root cap. E) epidermis of large woody roots. Answer: A 57) Diffusion doesn't require energy. Why do plants expend energy to actively transport minerals into root hairs? A) Minerals are strongly attracted to soil particles. B) Mineral concentrations in the soil are too high for diffusion. C) Mineral concentrations in the soil are too low for diffusion. D) Minerals are too large for diffusion. Answer: C 58) Mycorrhizae are symbiotic associations between fungi and plant A) roots. B) stems. C) seeds. D) leaves. E) flowers. Answer: A 59) All of the following are part of a plant's shoot system EXCEPT A) leaves. B) flowers. C) buds. D) stem. E) mycorrhizae. Answer: E 60) What are plasmodesmata? A) Transport channels for sugars B) Nutrients that can be used only by plants C) Root hairs that are adapted for mineral transport D) Organelles that manufacture ATP inroots E) Pores that connect the cytosol of neighboring cells Answer: E

61) What cellular feature allows a mineral such as manganese to diffuse from cell to cell after being taken up by roots? A) Sieve plates B) Microtubules C) Secondary cell walls D) Microfilaments E) Plasmodesmata Answer: E 62) What would happen if Casparian strips were not present and water and minerals could pass between endodermal cells of the plant root rather than through endodermal cells? A) An increased concentration gradient of the minerals in the extracellular space of the vascular cylinder would be better maintained. B) Too much energy would be needed to move the minerals between endodermal cells. C) The minerals would enter the conduction vessels of the vascular cylinder much more rapidly. D) Root hairs would lose their ability to take up minerals. E) Minerals would leak back out of the extracellular space of the vascular cylinder as fast as they were pumped into it. Answer: E 63) Mycorrhizae are A) mutualistic relationships between a fungus and an alga. B) parasitic relationships between bacteria and the roots of a land plant. C) commensal relationships between a fungus and the leaves of a land plant. D) symbiotic relationships between a fungus and the roots of a land plant. E) symbiotic relationships between bacteria and the roots of a land plant. Answer: D 64) Why can't plants use N2 directly as a nutrient? A) N2 diffuses out of leaves as quickly as it diffuses in, so it has to be "fixed" to remain in leaves. B) Plants lack the enzymes necessary to convert N2 into NO3−or NH4+. C) Plants must use NO3− to carry out nitrogen fixation. D) Most soils are depleted of N2 as a nutrient. E) The N2 molecule is too large to enter the stomata. Answer: B 65) Trees are among the largest and oldest living things on Earth. Like all life on Earth, the majority of a tree's biomass is carbon based. What is the source of this carbon? A) Water B) Air C) The organic layer of thesoil D) Fertilizers E) Crushed rock and water Answer: B

66) Bacteria-containing nodules in the roots of legume plants aid in the utilization of A) water. B) carbon dioxide. C) trace elements. D) phosphates. E) nitrogen. Answer: E 67) The mechanism explains the movement of water and minerals through xylem. A) bulk-flow B) assisted diffusion C) translocation D) cohesion-tension E) pressure-flow Answer: D 68) Water loss through the stomata of leaves is called A) bulk flow. B) osmosis. C) translocation. D) transpiration. E) guttation. Answer: D 69) With regard to the cohesion-tension mechanism, "cohesion" refers to the A) use of water in photosynthesis, resulting in a shortage of water in the leaf. B) process of osmosis that pulls water into the root. C) tendency of water molecules to be attracted to minerals in the water. D) evaporation of water from the stomata of the leaf. E) attraction of water molecules for one another. Answer: E 70) A plant, by opening and closing its stomata, must achieve a balance between A) sugar loss and oxygen uptake. B) oxygen loss and water uptake. C) carbon dioxide loss and sugaruptake. D) carbon dioxide uptake and oxygenloss. E) water loss and carbon dioxideuptake. Answer: E 71) An opening in the epidermis of the leaf through which water evaporates is called a A) guard cell. B) stoma. C) sieve plate. D) plasmodesmata. E) pit. Answer: B

72) When potassium ions are transported into guard cells, water A) leaves the guard cells by osmosis. B) is actively transported into the guard cells. C) enters the guard cells by osmosis. D) is actively transported out of the guard cells. E) moves to the edge of the guard cell. Answer: C 73) Which essential plant nutrient regulates the opening and closing of pores in the leaves? A) Iron B) Potassium C) Phosphorus D) Calcium E) Copper Answer: B 74) Which of the following bonds explains the cohesion of water molecules in the cohesion-tension mechanism? A) Peptide B) Hydrogen C) Ionic D) Disulfide E) Covalent Answer: B 75) During the spring, newly emerging leaves are sugar A) sources; sinks B) sinks; sinks C) sinks; sources D) sources; sources

and tree roots are sugar

Answer: A 76) Which of these organisms helped biologists determine the contents of phloem? A) Aphids B) Termites C) Grasshoppers D) Leafhoppers E) Ants Answer: A 77) The most widely accepted explanation for the transport of sugar-containing fluids in phloem is the mechanism. A) bulk flow B) cohesion-tension C) pressure-flow D) root pressure E) transpiration Answer: C

78) In summer, when plant roots are converting sugar to store as starch, the root is the sugar leaves are the sugar . A) sink; source B) sink; sink C) source; source D) sink; source or sink E) source; sink

and the

Answer: A 79) Ground tissue is found in the primary plant only, never in the secondary plant. A) True B) False Answer: B 80) The concentration of nutrients in plants is approximately the same as the concentration of nutrients in the surrounding soil. A) True B) False Answer: B 81) Water flows upward in some xylem tubes and downward in others. A) True B) False Answer: B SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 82) Phloem sieve-tube elements are able to remain alive because adjacent the form of proteins and high-energy compounds such as ATP.

cells provide nourishment in

Answer: companion 83) On a stem, branches grow and develop from the .

, whereas on the roots, branches grow and develop from

Answer: lateral buds; pericycle 84) Guard cells control the opening and closing of plant stomata by creating osmotic gradients across their membranes, which are adjusted by regulating the concentration of in their cytoplasm. Answer: potassium ions 85) In the spring, when stored starches convert back to sugars and move from the root of a plant to the developing buds, the root is the sugar and the bud is the sugar . Answer: source; sink 86) Based on your understanding of the key differences between monocots and dicots, what characteristics can you see with your naked eye that can help you distinguish between them? Answer: Number of flower parts (multiples of three for monocots; multiples of four or five for dicots), leaf venation (parallel for monocots; netlike for dicots), leaf shape (narrow for monocots; palmate or oval for dicots), and root type (fibrous for monocots; taproot for dicots)

87) Compare the functions of roots with those of shoots. How are they similar and how are they different? Answer: Both are involved in hormone production, support, and transport. Roots absorb water and minerals while consuming and/or storing carbohydrates, whereas shoots (including the leaves) consume water and minerals while producing carbohydrates. 88) Both primary and secondary growth are accomplished by mitotic cell division. Compare and contrast these two types of growth. Answer: Primary growth involves apical meristem cells and occurs in the growing tips of roots and shoots. Differentiation following division is responsible for specialized plant structures. Secondary growth occurs by the division of lateral meristem cells and causes stems and roots to become thicker and woodier. 89) You discover several woody bushes growing in your yard. Is it safe to assume that they are perennials? Why or why not? Answer: Yes; woody secondary growth occurs only in perennials. 90) What is the source of energy for plant roots? Answer: Photosynthesis in the shoot (leaves) uses the sun's energy to form sugars. The sugar must be transported to the plant roots in the phloem. Cellular respiration then makes this energy available to the root. 91) Plants need to minimize water loss while maximizing carbon dioxide intake. With respect to plant leaf structure, how are these conflicting needs met? Answer: The cuticle acts as a waterproof barrier at the leaf surface: guard cells and stomata regulate the intake of carbon dioxide as well as the loss of water vapor, and leaf shape can act to reduce water loss if the surface area is reduced. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 92) Based on the figure, estimate the age of this tree in years.

A) 8 to 10 B) 3 to 5 C) 20 to 25 D) over 35 E) 13 to 15 Answer: C

93) The guard cells shown in this figure have

A) lost most of their water. B) lost potassium ions. C) accumulated potassium ions. D) eliminated all potassium ions. Answer: C 94) You found the following plants growing on campus during a field trip: a small plant with a notable absence of root hairs; a short, stubby plant with an enlarged taproot; a tall annual herb with fungal strands extending from its roots; a low-growing plant with nodules on the roots; and a woody shrub with an extensive fibrous root system. Based on this scenario, which plant is most likely a legume with nitrogen-fixing bacteria? A) The plant with no roothairs B) The annual herb with the fungal-root association C) The woody shrub with the fibrous root system D) The plant with the enlargedtaproot E) The plant with the root nodules Answer: E 95) Several chemical pollutants from a paper mill are released into the nearby environment. Compound A is rich in calcium and magnesium. Compound B binds tightly to all free polypeptides and proteins in the soil. Compound C is structurally similar to abscisic acid. Based on this scenario, which compound will most likely harm the surrounding vegetation, and what effect(s) will it have on theplants? A) Compound A, because these minerals will act as toxins to the plant as they are absorbed through the roots. B) Compound C, because abscisic acid inhibits the active transport of potassium ions and thus closes the stomata, which will interfere with CO2 uptake and H2O transport. C) Compound B, because it ties up free polypeptides and proteins in the soil, preventing their uptake by plants, which is critical for plant growth. Answer: B

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Spores and gametes are both haploid reproductive cells. What is the difference between the two? A) Spores fuse to form a diploid zygote that eventually becomes the sporophyte, gametes. B) Spores are found only in plants that reproduce asexually, and gametes are found only in plants that reproduce sexually. C) Gametes germinate and grow into a multicellular haploid gametophyte, and spores carry out fertilization. D) Spores germinate and grow into a multicellular haploid gametophyte, and gametes fuse to form a diploid zygote. Answer: D 2) Ferns and mosses mainly live in A) arid B) moist C) desert D) sterile

environments.

Answer: B 3) A plant, such as an iris, that reproduces asexually most of the time probably A) produces offspring that move into new environments. B) is found in a changingenvironment. C) forms spores. D) lacks the ability tomake flowers. E) has offspring that live in the same environment as the parents. Answer: E 4) If you see moss near the base of a tree in your yard, the green leafy moss plants are A) zygotes. B) sporophytes. C) gametes. D) gametophytes. E) spores. Answer: D 5) An oak tree is a A) spore. B) gametophyte. C) gamete. D) zygote. E) sporophyte. Answer: E 6) In general, the plant life cycle has evolved from A) dominant spore; dominant gamete B) dominant gamete; dominant gametophyte C) dominant gametophyte; dominant sporophyte D) dominant sporophyte; dominant gametophyte E) dominant gamete; dominant spore Answer: C

7) In general, plants have evolved from A) fruit; seedless B) seedless; seed C) diploid; haploid life cycle D) seed; seedless E) no fruit; no spores

Answer: B 8) The sexual life cycle of plants is described as alternation of generations because it alternates between A) flowers and spores. B) eggs and sperm. C) reproductive plants and vegetative plants. D) sporophytes and gametophytes. E) male plants and female plants. Answer: D 9)

The sporophyte produces A) gametes by meiosis. B) spores by mitosis. C) gametes by mitosis. D) spores by meiosis. E) gametes by mitosis, followed by meiosis. Answer: D 10) In the alternation of generations, what is formed when a spore germinates? A) A plant that meiotically produces sex cells. B) A plant that produces spores when mature. C) A haploid stage called thegametophyte. D) A haploid stage called thesporophyte. E) An increased number of spores. Answer: C 11) In the life cycle of a fern, the large fern plant that we normally see is the A) zygote. B) spore. C) gamete. D) sporophyte. E) gametophyte. Answer: D 12) In the fern life cycle, how do spores and gametes differ? A) Gametes are easily visible to the unaided eye; spores are not. B) Gametes are diploid; spores are haploid. C) Spores are produced mitotically; gametes are produced meiotically. D) Gametes are produced by the sporophyte. E) Meiotic cell division produces haploid spores; mitotic cell division produces haploid gametes. Answer: E

13)

results in the production of spores in flowering plants. A) Mitosis B) Spermatogenesis C) Fertilization D) Meiosis E) Germination Answer: D

14) Which of the following has a gametophyte that is an independent plant that dominates the life cycle and does NOT have a sporophyte that is an independent plant? A) Rose B) Pine C) Fern D) Moss Answer: D 15) Which of the following is "male" in the life cycle of angiosperms? A) Seed cone B) Pollen grain C) Endosperm D) Embryo sac E) Megaspore mother cell Answer: B 16) In flowering plants, the sperm does not have to swim to the egg. The sperm reaches the eggs by A) cell division within the sporecase. B) digestion of the seed coat. C) burrowing through the embryo sac wall. D) wind pollination. E) a pollen tube. Answer: E 17) Angiosperms with wind-dispersed pollen include A) mosses. B) ferns. C) pine trees. D) roses. E) grasses. Answer: E 18) A pollen grain is actuallythe A) male gametophyte. B) female gametophyte. C) primitive egg cell, which will develop into the embryo. D) megaspore mother cell. E) combination of male and female gametophytes. Answer: A

19) Conifers do not have flowers to attract pollinators. Instead, fertilization occurs A) when insects coated with pollen are trapped in the sticky resin. B) when the endosperm takes the place of the male gametes. C) when birds transfer pollen in their droppings after eating the pine seeds. D) as the sperm and egg unite inside the woody cone. E) via wind pollination. Answer: E 20) During a late-summer walk through a park, you notice a tree that has remnants of many flowers but no fruits or seeds developing. There are no other trees like this one in the area. What could explain this occurrence? A) It is actually a gymnosperm, not an angiosperm. B) It is a species that reproduces only by runners, not via fruits (or the seeds they contain). C) It is a male tree with only male flowers that produce pollen, but no seed, and hence does not form fruit. D) It is a female tree, and there are no known male trees of the same species in the area. Answer: C 21) Grass flowers lack petals and sepals. Which of the following statements is TRUE? A) They are incomplete flowers lacking one or more floral parts. B) They are pollinated by flies, which don't require showy, scented petals. C) They are imperfect flowers lacking stamen or carpals. D) These flowers are pollinated at night, so they don't benefit from showy petals or sepals. Answer: A 22) Flowers that make pollen, but not ovules, lack A) petals. B) stamens. C) sepals. D) filaments. E) carpels. Answer: E 23) All of these flower structures are modified leaves EXCEPT A) carpels. B) stamens. C) sepals. D) pollen. E) petals. Answer: D 24) An incomplete flower A) remains in the bud stage and does not bloom. B) is incapable of self-fertilization. C) lacks one or more of the four basic floral parts. D) produces sterile seeds. E) manufactures infertile pollen. Answer: C

25) All of the following are included in the male parts of a flower EXCEPT A) pollen. B) ovules. C) stamens. D) anthers. Answer: B 26) The American holly tree requires a "male" tree and a "female" tree to produce red berries in the winter, which indicates that the male flowers lack and the femaleflowers lack . A) petals; ovules B) carpels; stamens C) anthers; stamens D) petals; carpels E) sepals; anthers Answer: B 27) A flowering plant produces pollen in the A) style. B) stigma. C) anther. D) ovule. E) fruit. Answer: C 28)

are modified leaves that are often green and surround the flower bud. A) Petals B) Sepals C) Ovules D) Filaments E) Stigma Answer: B

29)

are modified leaves that are often brightly colored and scented to attract pollinators. A) Stigma B) Petals C) Filaments D) Anthers E) Sepals Answer: B

30) The female reproductive structure, the carpel, consists of A) sepals, petals, and ovary. B) filament, anther, and pollen. C) stigma, style, and ovary. D) stigma, filament, and sepals. E) stamen, sepals, and filament. Answer: C

31) Which of the following is TRUE for female reproductive structures in angiosperms? A) The stamen includes the filament and pollen-producing anther. B) The carpel includes a stigma, a style, and ovules enclosed within an ovary. C) The sepals are contained within the petals, which enclose the carpel. D) The style, which is vase-shaped, contains the ovary, stigma, and anther. E) The filament and anther enclose the stigma and style. Answer: B 32) The male reproductive structure, the stamen, consists of A) a filament that bears ananther. B) a carpel enclosed in the petals, then the sepals. C) a single sepal, four or more petals, and the entire carpel. D) the stigma, style, and ovary. E) one or more sepals, the style, and one or more anthers. Answer: A 33) Which of the following statements is TRUE? A) When mature, the carpel will become the seed and the anther will become the fruit. B) When mature, the ovules will become seeds and the ovary will develop into a fruit. C) The filament and anther enclose the stigma and style. D) The style, which is vase-shaped, contains the ovary, stigma, and anther. E) When mature, the stamen will become the seed and the stigma will become the fruit. Answer: B 34) The male gametophyte of flowering plants is produced by cell divisions within the A) sepal. B) stigma. C) anther. D) filament. E) carpel. Answer: C 35) What is the evolutionary significance of a flower that has large, brightly colored petals? A) Such flowers produce only microspores or megaspores, not both. B) These flowers attract pollinators that are animals. C) The wind is a significant factor in pollination, especially because of the large petals. D) In general, these are aquatic plants, and water aids in their pollination, regardless of color and odor. E) Such plants are usually self-pollinators and do not rely on external factors for pollination. Answer: B 36) Meiosis produces a A) pollen tube B) sepal C) microspore D) sporophyte E) megaspore

, which eventually gives rise to an egg in an unfertilized seed.

Answer: E

37) Which of the following undergoes meiosis during the development of pollen grains? A) Megaspore mother cell B) Microspore C) Megaspore D) Generative nucleus E) Microspore mother cell Answer: E 38) All of the following are processes that occur during angiosperm reproduction EXCEPT A) the tube cell produces the pollen tube. B) the megaspore mother cell undergoes meiosis to produce four haploid megaspores. C) one megaspore degenerates, and the other three divide once to produce the six-celled embryo sac. D) the microspore mother cell undergoes meiosis to produce four haploid microspores. E) the generative cell forms two sperm cells via mitosis. Answer: C 39) In the development of a plant's ovule, the result is a gametophyte made up of A) eight haploid, uninucleate cells. B) seven binucleate cells and one haploid cell. C) seven cells: six haploid cells and one cell with two nuclei. D) seven diploid cells and one haploid cell. Answer: C 40) In flowering plants, the unfertilized ovule contains the A) stigma. B) embryo. C) female gametophyte. D) endosperm. E) pollen grain. Answer: C 41) The immature angiosperm pollen grain consists of a tube cell and a generative cell that will divide to produce sperm cells. A) one B) two C) three D) four Answer: B 42) Endosperm has allowed the angiosperms to become the most numerous and diverse plant group. What is the role of the endosperm? A) It is a type of male gamete. B) It is the hard outer seed coat that protects the embryo. C) It ejects and disperses seeds after they mature. D) It provides nutrition for the developing embryo, therefore increasing survival rates. E) It is the ripened ovary tissue involved in seed dispersal and protection. Answer: D

43) What are the results of double fertilization? A) Egg cell and sperm cell B) Embryo sac and pollen sac C) Diploid zygote and diploid endosperm D) Triploid endosperm and diploid zygote E) A zygote and an embryo Answer: D 44) The first leaves produced by an embryo while still inside the seed are A) epicotyls. B) embryo sacs. C) coleoptiles. D) cotyledons. E) endosperms. Answer: D 45) Cotyledons, or "seed leaves," absorb food molecules stored in the A) endosperm. B) ovary wall. C) gametophyte. D) megaspore. E) sporophyte. Answer: A 46) When wheat is processed to make white, all-purpose flour, the wheat is passed through rollers that pop off the embryo and the ovary wall. Some people add "wheat germ" to the white flour used to make baked goods in order to increase the protein content of these products. What is wheat germ? A) Bran B) Endosperm C) Wheat fruit D) Embryo E) Wheat flour Answer: D 47) The seed coat develops from the A) endosperm. B) integuments of the ovule. C) female gametophyte. D) wall of the pollen sac. E) ovary wall. Answer: B 48) A fruit is a mature A) embryo. B) integument. C) endosperm. D) ovary. E) cotyledon. Answer: D

49) You have some freshly produced seeds that refuse to germinate when placed in moist soil. What can you do to break dormancy and encourage the seeds to germinate? A) Freeze them, then follow up with sufficient warmth and moisture. B) Put them in sunlight. C) Put them in the dark. D) Treat them with abscisic acid. E) Boil them. Answer: A 50) Plants that grow in areas most likely do not require drying or exposure to cold to break dormancy were it to occur. A) arctic B) subtropical or tropical C) northern temperate D) desert Answer: B 51) Cotyledons and endosperm both provide nutrition. What is the difference between them? A) Endosperm is found only in monocots; cotyledons are found only in dicots. B) Cotyledons provide nutrition for the developing embryo; endosperm provides nutrition for the young seedling. C) Cotyledons are found only in flowering plants; endosperm is found only in young ferns. D) Endosperm is always photosynthetic; cotyledons are usually not. E) Endosperm provides nutrition for the developing embryo; cotyledons provide nutrition for the young seedling. Answer: E 52) Desert plants often have complete their life cycle. A) drying agents B) digestive enzymes C) wetting agents D) cold-sensitive compounds E) water-soluble chemicals

in their seed coats that keep them dormant until there is enough rain to

Answer: E 53) In many dicots, the first pair of leaves to emerge from the soil after seed germination is completely unlike all the rest of the leaves that form on that plant. In such plants, these leaves are A) derived from the root, not the shoot. B) made from the opening and greening of the coleoptile. C) formed from the endosperm. D) made from the epicotyl hook. E) cotyledons, which have elongated and turned green. Answer: E

54) In monocots, the shoot tip is protected by A) a slime layer formed by the shoot cells B) the hypocotyl C) thecoleoptile D) cotyledons E) the epicotyl

, which eventually degenerate(s) once exposed to air.

Answer: C 55) In dicots, the shoot tip is protected by A) a slime layer formed by the shoot cells. B) the hypocotyl hook. C) a woody sheath around theepicotyl. D) the coleoptile. Answer: B 56) Some very showy desert flowers avoid desiccation of delicate floral tissues by blooming at night. They are pollinated by A) hummingbirds. B) bats. C) bees. D) wind. Answer: B 57) Yucca flowers are pollinated only by yucca moths, which lay their eggs in the flower's ovary. This interaction ensures that the plant has seed for the next plant generation and that the moth larvae have a food source to develop. What is a potential disadvantage or vulnerability of this very specialized plant-animal interaction? A) Pollination can occur only during the day, but the moths are most active at night. B) If the moths are exterminated by insecticides, the plant-animal interaction ceases and the plant will no longer be pollinated or reproduce. C) The plant ovary may be consumed by the larvae, which would kill all the developing seeds. D) Other moths that do not serve as pollinators may outcompete the yucca moths. Answer: B 58) Which of the following pollinators would likely visit a flower that is relatively simple in design and smells like rotting carrion? A) Hummingbirds B) Butterflies C) Beetles D) Bees E) Moths andbutterflies Answer: C 59) All of the following are true of the relationship between the yucca and the yucca moth EXCEPT A) some of the developing yucca seeds feed the yucca caterpillars. B) the yucca plant is dependent on the yucca moth to reproduce, but the yucca moth can lay its eggs in any of several kinds of flowers. C) the yucca moth spreads pollen on the stigma of the yucca flower in which it lays its eggs. D) the female moth collects yuccapollen. E) the moth lays its eggs directly inside the yucca ovary, where its eggs hatch into caterpillars. Answer: B

60) While walking along a riverbank after a swim, you step on a sharp fruit. When you pick it up, you notice that it rattles, which indicates there is an air pocket around the seeds. How is this fruit most likely dispersed? A) Water B) Being eaten by animals C) Explosively propelled D) Clinging to animals E) Wind Answer: A 61) The aptly named dead horse arum has a heat-producing flower. What advantage does this heat provide? A) It creates a barrier to invasive plant species. B) It increases the evaporation of the scent, attracting pollinators from greater distances. C) It prevents inefficient pollinators from collecting pollen. D) It warms the pollinators, which are usually bats. E) It enables blooms to emerge through snow. Answer: B 62) Asexual reproduction is rare in plants. A) True B) False Answer: B 63) In angiosperms, but not conifers, pollen grains can form pollen tubes. A) True B) False Answer: B 64) Throughout the world, the most common types of plants are the flowering plants. A) True B) False Answer: A 65) Megaspore mother cells are diploid. A) True B) False Answer: A 66) The process in flowering plant reproduction in which the first sperm unites with an egg to form a diploid zygote and the second sperm unites with two haploid polar bodies to form the diploid endosperm is called double fertilization. A) True B) False Answer: B 67) The female gametophyte of angiosperms is made up of eight diploid cells and one haploid egg cell. A) True B) False Answer: B

68) When we consume whole grains, we are eating endosperm. A) True B) False Answer: A 69) Most "hay fever" is actually caused by ragweed, and not hay grass. A) True B) False Answer: A SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 70) A diploid fertilized egg is called a(n)

Answer: zygote 71) When you eat a cherry, you know that the fruit was derived from the the .

and the seed was derived from

Answer: ovary; ovule 72) In temperate deciduous forests, most of the small flowers that grow on the forest floor must complete their life cycle quickly before tree leaves shade out most of the light. Many of these plants reproduce asexually by runners. What advantages does this have for such plants? Answer: The environment that the offspring occupy is the same as that of the parents, so the offspring are likely to do well if they are identical to the parents. If the flowers do not get pollinated during their brief life span, the plant is still able to reproduce. Also, the offspring get nutrition from the parent. 73) Describe the process of alternation of generations in plants. Answer: The haploid gametophyte produces gametes by mitosis, and the diploid sporophyte produces spores by meiosis. 74) In primitive land plants, such as mosses and ferns, how does the sperm get to the egg? Answer: The sperm must swim through a film or drop of water. 75) What is the function of the stigma of a flower? Answer: It serves as a sticky landing site for pollen. 76) What are the advantages of producing gametes within a flower? Answer: This helps with reproduction on land because the male gamete and the embryo are produced within waterproof coats. This allows the plant to invade drier environments. In addition, the sperm can be released within the female gametophyte. 77) In the ovule, which two cells (with a total of three nuclei) are fertilized? Answer: the two nuclei in the primary endosperm cell and the egg cell 78) Why is fertilization in flowering plants called double fertilization? Answer: One sperm fertilizes the egg cell, and the other sperm fertilizes the endosperm cell. 79) How many sperm nuclei are necessary for the successful fertilization of flowering plants? Answer: two

80) What two key adaptations in plants were necessary for insect pollination to be successful? Answer: sufficient amounts of pollen or nectar produced in proximity to the stigma, and advertising in the form of petals to attract the insect to the area 81) Briefly describe how a seed develops from the ovule. Answer: There are three processes: (1) the integuments of the ovule thicken, harden, and become the seed coat that surrounds and protects the seed; (2) the triploid central cells undergo mitosis, and then the daughter cells absorb nutrients and form an endosperm; (3) a zygote develops into an embryo. 82) When a seed germinates, what usually emerges from the seed coat first? Why? Answer: The root emerges first because it can absorb water and nutrients from the soil. 83) Plants that live in temperate latitudes often make seeds that exhibit dormancy. What is the advantage of having dormant seeds for plants in these areas? Answer: Without dormancy, warm autumn temperatures would cause the seeds to germinate. The delicate seedlings would then be killed by cold winter weather. 84) Both monocots and dicots protect their young shoots as they emerge from the soil. Describe how each group accomplishes this. Answer: In monocots, the coleoptile protects the shoot tip; dicots form an epicotyl or hypocotyl hook. 85) Commercials on TV use food and sex as their most effective selling points. Explain how flowers use the same two points to "sell" their pollen to animals. Answer: Plants have flowers that contain sugar-rich nectar (food) or mimic potential mates (sex) to attract animal pollinators. 86) What are the typical shape, color, and nectar content of a flower that is pollinated by a hummingbird? What are the traits of a bee-pollinatedflower? Answer: Hummingbird-pollinated flowers have a deep, tubular shape; red coloration; and a large amount of nectar. Bee-pollinated flowers are shallow, reflect near-UV light, and have smaller amounts of nectar. The differences in the flowers are the result of the inherent differences in the pollinators.

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 87) Based on the leaflike sepals in the flower shown in the figure and on the other visible characteristics, this flower is a(n)

A) complete monocot flower. B) incomplete monocot flower. C) incomplete dicot flower. D) complete dicotflower. Answer: D 88) Based on thefigure, the

must have contained two nuclei before fertilization.

A) central cell B) zygote C) integument cell D) embryo Answer: A

89) A group of geneticists exposed the seeds of a dicot plant to various levels of radiation in order to induce random mutations. Many of the irradiated seeds failed to germinate. Some of the seeds, however, germinated in the lab and were carefully studied. The scientists discovered a mutation that prevents the formation of a hypocotyl hook during germination. Based on this scenario, the mutant plant most likely germinated A) but damage to the cotyledons prevented the seedlings' emergence from the soil. B) and grew like a normal plant. C) but was unable to photosynthesize. D) but the mutated hypocotyl hook caused damage to the emerging root tip. E) but the mutated hypocotyl hook failed to push the cotyledons above the soil. Answer: E 90) In north-central Florida, the cars, homes, streets, and ponds are covered with an impressive coating of bright yellow dust every spring. Upon closer, microscopic examination, the yellow "dust" turns out to be pollen grains. This area of Florida has pine trees, showy daytime-flowering plants, and often-unnoticed nighttime-flowering plants, with sweet-scented flowers, releasing pollen at the same time of year. Based on this information, which group of plants do you think is responsible for the yellow pollen? Why? A) The nighttime-flowering plants are responsible. Because they spend energy producing sweet-scented flowers that attract bat and moth pollinators, nighttime-flowering plants need to produce lots of pollen for the bats and moths toeat. B) The pines are responsible, because conifers are pollinated by wind and must produce enormous amounts of pollen in order to ensure that some of it reaches the female cones. C) The daytime-flowering plants are responsible. Because they spend energy producing showy flowers that attract animal pollinators, daytime-flowering plants need to produce lots of pollen for the animals to eat. Answer: B

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) How is the carnivorous plant lifestyle suited for an existence in bogs? A) Bogs are naturally high in nitrogen, which favors the carnivorous plant lifestyle. B) The lack of nitrogen in bogs selects for the carnivorous plant lifestyle of ingesting and digesting animals for nitrogen. C) Bogs contain rich populations of nitrogen-fixing bacteria, which provide nitrogen to the plants. D) Bogs contain many soil-based proteins, which are a good source of nitrogen. Answer: B 2) How a plant cell responds to a hormone depends on the A) "shelf life" of thehormone. B) concentration of the hormone. C) amount of available sunlight. D) cell that secretes the hormone. E) presence of other plant cells nearby. Answer: B 3) After seeds were planted, some of the seedlings did not emerge from the soil. Is it possible they did not grow because some of the seeds were planted upside down? A) No; sunlight penetrates soil to the depth of seeds and shoots grow toward the sunlight. B) Yes; if the seed was oriented so that the embryonic shoot pointed down, it would grow in that direction because sunlight doesn't reach it. C) No; gibberellins and abscisic acid, in balanced concentrations, cause shoots to grow away from gravity. D) Yes; after seeds are planted, water and settling of the soil may cause them to shift in their orientation. E) No; auxins in the shoots cause curvature away from gravity. Answer: E 4) Why do bananas in a bag ripen so much faster than bananas on a counter top? A) Auxins are present in low concentrations in the bag because sunlight stimulates the production of this hormone. B) The bag holds in moremoisture. C) Cytokinins are present in low concentrations in the bag because sunlight stimulates the production of this hormone. D) Abscisic acid, produced by the fruit, is trapped in the bag. E) Ethylene, produced by the fruit, is trapped in the bag. Answer: E 5) A plant's tendency to grow toward a source of light is called A) phototropism. B) lumitropism. C) gravitropism. D) amylotropism. E) thigmotropism. Answer: A

6) Pea plant tendrils wrapping around a string demonstrate A) phototropism. B) lumitropism. C) gravitropism. D) amylotropism. E) thigmotropism. Answer: E 7) Tomatoes that are planted upside down still grow upright, displaying A) phototropism. B) lumitropism. C) gravitropism. D) amylotropism. E) thigmotropism. Answer: C 8) A scientist who claims to have discovered a new plant hormone must demonstrate that this compound is A) produced in large amounts. B) capable of stimulating differentiated cells to form meristem tissue. C) formed in one part of the plant but has an effect in a different part. D) needed by the plant as a major source of energy. E) made from cell proteins. Answer: C 9)

Gravitropism is a plant's A) apical dominance. B) response to stress-inducing situations. C) ability to form an abscission layer, so that the fruits and leaves fall from the plant. D) directional response to gravity. E) ability to grow only upward. Answer: D 10) The synthetic herbicide 2,4-D is actually a(n) A) auxin. B) cytokinin. C) ethylene gas. D) florigen. E) gibberellin. Answer: A 11) The hormone A) ethylene B) auxin C) cytokinin D) gibberellin E) florigen

was named after the fungus that causes "foolish seedling" disease in rice.

Answer: D

12) Why does removing an overripe, mushy apple from a container of otherwise good apples help preserve the good apples? A) Ethylene production in the good apples is inhibited by the lack of ethylene production in the overripe apple. B) The overripe apple makes ethylene gas, which can cause the good apples to ripen more quickly than usual. C) Gibberellins help preserve the goodapples. D) Chemicals in the overripe apple stimulate the conversion of sugar to starch in the good apples. E) The production of cytokinins is inhibited in the remaining good apples. Answer: B 13) Roots grow downward and shoots grow upward due to A) cytokinin. B) auxin. C) abscisic acid. D) gibberellin. E) ethylene. Answer: B 14)

triggers the formation of weak-celled abscission layers in leaves and fruits, allowing them to drop off at appropriate times during theyear. A) Auxin B) Ethylene C) Abscisic acid D) Gibberellin E) Cytokinin Answer: B

15) Seed germination is stimulated by A) cytokinin. B) abscisic acid. C) florigen. D) gibberellin. E) ethylene. Answer: D 16) Which of these hormones helps plants tolerate drought and cold? A) Ethylene B) Auxin C) Gibberellin D) Abscisic acid E) Cytokinin Answer: D 17) If you want to keep cut flowers fresh, treat them with A) abscisic acid. B) gibberellin. C) ethylene. D) cytokinin. E) auxin. Answer: D

18) In 2007, research confirmed the existence of hormones that control the timing of flowering. These hormones are called A) florigens. B) cytokinins. C) abscisic acids. D) auxins. E) ethylenes. Answer: A 19) A botanist who wants to stimulate flower formation in response to light cues could treat the plants with A) florigen. B) abscisic acid. C) ethylene. D) cytokinin. E) auxin. Answer: A 20)

maintains seed dormancy, and ends seed dormancy by stimulating enzymes that break down the food reserves of the seed to fuel seedling growth. A) Abscisic acid; ethylene B) Cytokinin; auxin C) Auxin; cytokinin D) Abscisic acid; gibberellin E) Gibberellin; abscisic acid Answer: D

21) A species-specificratio of produced in the apical meristem and maintains a balance between shoot and root growth. A) abscisic acid; ethylene B) gibberellins; abscisic acid C) cytokinins; auxins D) abscisic acid; gibberellins E) auxins; cytokinins

produced in the root tips

Answer: E 22) What will happen to a long-day plant, such as spinach, if the light-dark pattern is interrupted by a flash of light for several days in a row during the spring? A) The plants won't flower thatseason. B) The plants are tricked into flowering earlier than usual. C) The plants will be delayed in flowering. D) Nothing will happen; growth and development will continue as normal. Answer: B 23) Placing a ripe apple in a bag of green bananas will cause the bananas to ripen quickly. This is because the apple A) forms digestive enzymes. B) makes auxin. C) produces ethylene gas. D) releases heat. E) absorbs cytokinin. Answer: C

24) Cutting a hedge with a trimmer stimulates it to become bushy because A) removing the apical meristems makes more auxin, which stimulates lateral branch buds to grow. B) removing the lateral buds results in apical dominance under the influence of cytokinins. C) removing the apical meristems results in less auxin, which results in more lateral branch growth. D) removing the apical meristems makes less ethylene, which stimulates lateral branches to grow. Answer: C 25) To encourage the formation of well-developed, heavily branched roots, you should treat cuttings with A) gibberellin. B) abscisic acid. C) ethylene. D) auxin. Answer: D 26) Suppose you have some seeds that refuse to germinate when placed in moist soil. What could you do to encourage the seeds to germinate? A) Treat them with gibberellin. B) Put them in direct sunlight. C) Boil them. D) Treat them with abscisic acid. E) Treat them with auxin. Answer: A 27) If you were running a tree nursery and wanted to keep your trees dormant until the customer could plant them, which hormone would you spray on the trees? A) Abscisic acid B) Auxin C) Ethylene D) Gibberellin E) Cytokinin Answer: A 28) The two hormones involved in seed germination and seed dormancy are A) auxin and ethylene. B) abscisic acid and gibberellin. C) gibberellin and auxin. D) cytokinin and auxin. E) ethylene and cytokinin. Answer: B 29) Ethylene A) stimulates seed germination. B) promotes gravitropism. C) causes phototropism. D) prevents leaf senescence. E) promotes leaf and fruit drop. Answer: E

30) Auxin A) promotes phototropism. B) inhibits stemelongation. C) stimulates flowering. D) causes the development of an abscission layer. E) promotes celldivision. Answer: A 31) Elongation of cells in stems is promoted by A) auxins and gibberellins. B) cytokinins and abscisic acid. C) enzymes and phytochromes. D) ethylene and cytokinins. E) abscisic acid andethylene. Answer: A 32) Abscisic acid enforces dormancy of seeds by A) preventing endosperm development. B) binding to the molecule ATP. C) waterproofing the seed coat. D) preventing the development of the embryo and completion of the lifecycle. E) activating gibberellin. Answer: D 33) What causes the "leaf drop" that occurs in woody plants in preparation for winter dormancy? A) Increased ethylene production B) Increased chlorophyll development C) Suppressed auxin production D) Opened stomata E) Inhibition of gibberellin Answer: A 34)

induces dormancy in seeds and buds and causes stomata to close. A) Abscisic acid B) Cytokinin C) Ethylene D) Gibberellin E) Auxin Answer: A

35) When auxin accumulates on the lower side of the shoot of a germinating seed, it A) increases cell elongation on the lower side of the shoot. B) decreases cell elongation on the lower side of the shoot. C) has no effect on the shoot; it affects only the developing root. D) decreases the use of energy by the cells in the shoot. E) increases the use of energy by the cells in the shoot. Answer: A

36) When auxin accumulates on the lower side of the root of a germinating seed, it A) decreases the use of energy by the cells in the root. B) increases cell elongation on the lower side of the root C) has no effect on the root; it affects only the developing shoot. D) decreases cell elongation on the lower side of the root. E) increases the use of energy by the cells in the root. Answer: D 37) The relative sizes of roots and shoots are regulated by interactions between A) auxins and cytokinins. B) abscisic acid and cytokinins. C) ethylene and abscisic acid. D) gibberellins and abscisic acid. E) cytokinins and ethylene. Answer: A 38) Which of these hormones causes cell elongation, promotes apical dominance, and stimulates root branching? A) Auxin B) Abscisic acid C) Ethylene D) Gibberellin E) Cytokinin Answer: A 39) Most scientists believe that the lateral buds nearest the top of a tree are most inhibited from sprouting because they A) receive the most auxin from the apical bud. B) are the most affected bygravity. C) are shaded by the apical bud and the top of the tree. D) are most exposed to thelight. E) produce gibberellins. Answer: A 40) Most scientists believe that the lateral buds farthest from the top of a tree are the least inhibited from sprouting because they A) receive the most cytokinins from the roots. B) are the most affected bygravity. C) produce gibberellins. D) receive the least light. E) are shaded by the top of the tree. Answer: A 41) If a plant is living under conditions that limit root growth, shoot growth is A) limited as well, due to less cytokinin being produced by the root. B) limited as well, due to more auxin being produced by the apical meristem. C) unaffected by the amount of root growth. D) stimulated, due to less cytokinin being produced by the root. E) stimulated, due to more auxin being produced by the apical meristem. Answer: A

42)

plants bloom only when the duration of uninterrupted darkness is shorter than a critical length. A) Phytochrome-system B) Gibberellin-regulated C) Neutral-day D) Short-day E) Long-day Answer: E

43) Which environmental factor is most significant for flowering? A) Temperature B) Nitrogen availability C) Day length D) Light intensity E) Water availability Answer: C 44) Short-day plants flower only if A) they are in the shade. B) their phytochrome-mediated responses are inhibited. C) the duration of uninterrupted darkness is longer than some species-specific length. D) abscisic acid is available. Answer: C 45) Which pigment is responsible for the phototropism responses of plants? A) Ethylene B) Chlorophyll C) Auxin D) Phytochrome E) Xanthophyll Answer: D 46) Which of the following is TRUE of the relationship between the phytochrome system and the biological clock of plants? A) The phytochrome system manufactures special cells that control the biological clock. B) The phytochrome system serves as the biological clock for plants. C) The biological clock detects light and sends the information to the phytochrome system. D) The phytochrome system detects light and resets the biological clock. E) There is no relationship between the phytochrome system and the biological clock. Answer: D 47) At night, when little red light is available to the plants in an area, what occurs? A) Pr is converted to Pfr. B) Pr stimulates flowering. C) Pr and Pfr are both destroyed. D) Pfr is converted to Pr. E) Pr and Pfr are both formed from inactive phytochrome. Answer: D

48) The phytochrome that is active and absorbs far-red light is A) Pa. B) Pr. C) Pe. D) Pfr. Answer: D 49) The phytochrome Pr A) is very unstable. B) is inactive and absorbs redlight. C) is the active form of Pfr. D) absorbs far-red light. Answer: B 50) The process of aging is called A) elongation. B) senescence. C) maturation. D) abscission. E) death. Answer: B 51) Senescence in plants usually involves A) apical dominance. B) shade from other plants. C) the formation of an abscission layer. D) the development of photosynthetic enzymes. E) the presence of cytokinins. Answer: C 52) If a storm breaks off the top of a tree, within a year or two, one of the lower branches will grow upward and become the new tree top, while inhibiting other branches from doing the same. This is an example of A) the influence of ethylene. B) the presence of cytokinins. C) the formation of an abscission layer. D) phytochrome inhibition. E) apical dominance. Answer: E 53) What happens to phytochromes after several days of dark, rainy weather? A) Pr and Pfr are both formed from inactive phytochrome. B) Pfr spontaneously reverts to Pr. C) Pr absorbs darkness and converts to Pfr. D) Pr stimulates flowering. E) Pr and Pfr become unstable and both are destroyed. Answer: B

54) Plants that flower in the United States only in the early spring (when nights are long) are A) day-neutral B) long-day C) short-day D) indeterminate-day E) night-determinate

plants.

Answer: C 55) Plants that flower in the United States in July (when nights are short) are A) day-neutral B) long-day C) short-day D) indeterminate-day E) night-determinate

plants.

Answer: B 56) A new type of strawberry plant produces fruit in the late spring, throughout the summer, and into the fall. It is a(n) plant. A) day-neutral B) long-day C) short-day D) indeterminate-day E) night-determinate Answer: A 57) What caterpillar saliva-based chemical stimulates a corn plant to release an alarm signal? A) Volicitin B) Methyl salicylate C) Salicin D) Salicylic acid E) Florigen Answer: A 58) Leaves of the Venus flytrap and other sensitive plants move quickly due to A) muscle-like plant cells called myophytes. B) an electrical stimulus and rapid diffusion of ions out of motor cells. C) hormones that cause plant cellmovement. D) reduced permeability to potassium ions. Answer: B 59) Some plants under attack by insects can communicate this information to other parts of the same plant and to nearby plants via A) the release of chemicals into the air. B) vibrations in their roots. C) low-frequency sound waves. D) the release of chemicals into their roots. Answer: A

60) Willow trees and many other plants produce A) salicylic acid B) volantin C) acetaminophen D) acetic acid E) nicotine

, from which aspirin ismade.

Answer: A 61) Radish plants under insect attack A) produce bitter chemicals and grow spines on their leaves. B) release salicin, which is converted to salicylic acid within the insect. C) rapidly fold their petioles together. D) produce the defensive toxin nicotine. Answer: A 62) Corn plants release chemicals that attract a parasitic wasp. The wasp, in turn, protects the corn plants from destruction by A) root worms. B) caterpillars. C) other wasps. D) too dry soils. E) stinging bees. Answer: B 63) Venus flytraps catch insects in order to supplement their input of A) phosphorus. B) nitrogen. C) meat. D) potassium. E) magnesium. Answer: B 64) Vibrations from an insect trapped inside a carnivorous sundew and thrashing around to escape stimulate the sundew's response. What happens next? A) The sundew's leaves snap shut and their spiked edges mesh, trapping the insect. B) Thigmotropism is activated, and it kills the insect. C) An electrical shock kills the insect. D) The plant secretes a cocktail of digestive enzymes that rapidly breaks down the insect's body. Answer: D 65) The only plant hormone that is a gas is cytokinin. A) True B) False Answer: B 66) Shoots grow up and roots grow down due to thigmotropism. A) True B) False Answer: B

67) Auxins are used in rooting powders to encourage the formation of well-branched roots. A) True B) False Answer: A SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 68) Cytokinins cause most of their responses in plants by stimulating cell

Answer: division 69) Plants are able to measure the length of the night using the

system.

Answer: phytochrome 70) When a peach blossom is pollinated, auxin and/or

stimulates the development of fruit from the ovary.

Answer: gibberellin 71) In the late winter, as seeds prepare to germinate, the levels of of are increasing.

in seeds should be declining as the levels

Answer: abscisic acid; gibberellins 72) How do auxin and cytokinin interact to affect the shape and growth of a plant? Answer: Auxin encourages the development of the main stem and inhibits lateral bud growth. Cytokinin encourages lateral bud growth. The interactions between the two determine the branching patterns and shape of the plant. 73) Defend this statement: Plants are just as capable of responding to their environment as are animals. Answer: Plants have tropisms, such as gravitropism, thigmotropism, and phototropism. Also, their stomata open and close in response to available moisture to regulate transpiration. 74) A Native American tradition uses a "tea" made by soaking willow bark in water as a pain-reliever. Does it work? Why? Answer: Yes, it works. The willow bark contains high levels of salicylic acid, which is the active ingredient in aspirin. 75) In seeds from northern areas, what plant hormone often needs to be removed to get them to germinate, and how can it be removed? Answer: abscisic acid, which can be destroyed by prolonged chilling 76) If a coleus plant becomes tall and spindly, what can you do to encourage it to develop lateral branches, so that it becomes bushier? Answer: Cut or pinch off the topmost (apical) bud so that apical dominance is lowered, allowing the lateral buds to develop. 77) Why can flowers be brought "into bloom" out of season by changing the duration of light and darkness? Answer: Plants measure the season by the duration of continuous darkness. Altering the light-dark pattern can trick the plants into thinking it is the appropriate time to bloom. 78) Ripening fruits are attached firmly to their trees, but once they are mature, the trees must release them. How does this happen? Answer: A weak layer of tissue, called an abscission layer, develops where the fruit stalk meets the stem. 12

79) What kinds of hormonal changes occur as trees prepare for winter dormancy? Answer: Cytokinin and auxin levels decrease, ethylene levels increase, and abscisic acid causes bud dormancy. 80) Plants, as prey, can't run away from their predators, but they can defend themselves. Is the predatory nature of Venus flytraps a defense mechanism, or does it serve some other purpose? Answer: Being predatory gives Venus flytraps an advantage by providing nitrogen in environments, such as bogs, where nitrogen is deficient. It is not a defense mechanism. 81) Misting tomato plants with wintergreen tea can help prevent mosaic virus from infecting the plant. How? Answer: The methyl salicylate in the wintergreen tea enhances the plants' immune response, making them more resistant to the virus (much like methyl salicylate in willow, alder, and birch trees increases the immune response to insect-caused infections). 82) What mechanisms do plants use to discourage predation? Answer: Some plants produce toxic chemicals within the plant itself (such as nicotine); other plants cause leaves to droop (as in sensitive plants). 83) If a poplar forest is attacked by gypsy moths, how do the trees around the infected area tend to become somewhat resistant? Answer: Plants that are attacked by insects tend to release hormones into the air to "warn" neighboring plants. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 84) What phenomenon is illustrated in the figure?

A) Gravitropism B) Thigmotropism C) Apicotropism D) Phototropism Answer: A

85) Based on the figure, which of the following plants will NOT flower under long-day or interrupted-night conditions?

A) Chrysanthemum B) Iris C) Rose Answer: A 86) The ideal Christmas tree has a conical shape. The top of the tree is pointed and narrow, with clear apical dominance, and the bottom of the tree is wide, with extensive lateral branching. Certain evergreen species are suitable for use as Christmas trees because they have this shape normally and thus require little pruning or training as they grow. For example, spruces and firs are often grown as Christmas trees, whereas yews and longleaf pines are not. Based on this information, spruces and firs are likely to have A) low levels of auxins near the top and low levels of cytokinins at the bottom of the tree. B) high levels of auxins near the top and low levels of cytokinins at the bottom of the tree. C) low levels of auxins near the top and high levels of cytokinins at the bottom of the tree. D) high levels of auxins near the top and high levels of cytokinins at the bottom of the tree. Answer: D

87) A group of plant geneticists discovers a mutant plant that has a deficiency in gibberellin production. All other hormones, including auxins, cytokinins, florigens, ethylene, and abscisic acid, are produced in normal quantities and are not directly affected by this mutation. Based on this scenario, the mutant plant most likely exhibits A) delayed senescence. B) a dwarf growth pattern (very short stem). C) a lack of phototropism in the shoots. D) stomata that don't close. E) a lack of gravitropism in the roots. Answer: B