Quiz

QUIZ

1. What statement is true?

a. Anabolism is molecular breakdown, which is endergonic. b. Catabolism is molecular breakdown, which is exergonic. c. Anabolism is molecular buildup, which is exergonic. d. Catabolism is molecular buildup, which is endergonic.

Answer: b. Catabolism is the breakdown of molecules, which releases heat and energy so these are exergonic reactions. Anabolism is the making or buildup of molecules, which requires energy so these are endergonic reactions.

2. Organisms that get their energy from inorganic molecules are called what?

a. Phototrophs b. Heterotrophs c. Autotrophs d. Lithotrophs

Answer: d. Lithotrophs are organisms that get their energy from inorganic molecules, such as reduced iron and hydrogen sulfide.

3. What is the main energy currency used in most energy-requiring reactions in the cell?

a. ATP b. NAD+ c. NADP+ d. FAD

Answer: a. Each of these reactions are helpful in energy needs of the cell, except that ATP is the main energy source in most metabolic processes in the cell.

4. What is not something that an enzyme does?

a. It lowers the activation energy of a reaction. b. It binds to the substrate of a reaction. c. It causes a conformational change to occur in a substrate. d. It is consumed as part of the reaction.

Answer: d. The reaction with an enzyme occurs because of each of these things. The exception that does not occur is that the enzyme is consumed as part of the reaction. The enzyme is not consumed in an enzymatic reaction.

5. When is the pentose phosphate pathway used instead of regular glycolysis?

a. When oxygen is not available b. When there are pentoses and not glucose available c. When nucleic acids or amino acids are needed d. When more ATP energy is required by the cell

Answer: c. The pentose phosphate pathway is used in all cells and is the preferred pathway when nucleic acids or amino acids are necessary because these can be made from this pathway’s intermediates. 6. What are the starting product and some end products of the Krebs cycle?

a. Pyruvate is the starting substrate and some end products are oxygen and

ATP. b. Pyruvate is the starting substrate and some end products are CO2 and

GTP. c. Acetyl CoA is the starting substrate and some end products are oxygen and

CO2. d. Acetyl CoA is the starting substrate and some end products are CO2 and

ATP.

Answer: d. The Krebs cycle starts with acetyl CoA and some end products are CO2, ATP, GTP, and NADH.

7. Which organism makes beer and bread because it participates in alcoholic fermentation?

a. Escherichia coli b. Staphylococcus aureus c. Lactobacillus species d. Saccharomyces cerevisiae

Answer: d. Saccharomyces cerevisiae is a yeast organism that makes CO2 in the making of bread and fermented alcoholic beverages.

8. Where does oxidative phosphorylation take place in prokaryotes?

a. Inner cell membrane b. Outer cell membrane c. Outer mitochondrial membrane d. Inner mitochondrial membrane

Answer: a. Oxidative phosphorylation takes place on the inner cell membrane of prokaryotes. They do not have mitochondria. In eukaryotes, the oxidative phosphorylation takes place on the inner mitochondrial membrane.

9. What gets made as part of beta-oxidation of lipids?

a. Acetyl groups b. Pyruvate c. Glucose d. Glucose-6-phosphate

Answer: a. Acetyl groups are 2-carbon molecules that participate in metabolism by entering the Krebs cycle to make CO2 and ATP energy.

10. What is the main end product of the light-independent processes in photosynthesis?

a. Amino acids b. Glucose c. CO2 d. Pyruvate

Answer: b. The end product of this type of metabolism is the making of sugar or glucose from CO2 as a beginning substrate.