Anatomy & Physiology for Health Professions, 3rd Edition
By Bruce J. Colbert
Email: Richard@qwconsultancy.com
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Chapter 1 INTRODUCTION TO ANATOMY AND PHYSIOLOGY: LEARNING THE LANGUAGE LEARNING OUTCOMES Understand the term anatomy and physiology and its various related areas. Construct and define medical terms using word roots, prefixes, and suffixes. Identify commonly used medical abbreviations. Contrast the metric and English systems of measures. Describe various signs and symptoms along with associated disease terminology. Explain the concepts and importance of homeostasis and metabolism. MULTIMEDIA FOUND ON THE POWERPOINT LECTURE OUTLINE 1. Medical Specialties Video (slide 31) 2. Vital Signs Video (slide 32) 3. Medical Assisting Video (slide 57) 4. Health Information Management Video (slide 58) 5. Medical Transcription Video (slide 59)
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LECTURE OUTLINE I. Introduction A. Medical terminology is the language of health professionals. B. This chapter lays the foundation for this language and for an introduction to anatomy and physiology (A & P). C. Future chapters build on this foundation to help students understand anatomy and physiology and become fluent in the language. II. What is Anatomy and Physiology? A. Anatomy 1. Anatomy is the study of internal and external structures of the human body. 2. Anatomy is Greek for “to cut apart.” 3. Microscopic anatomy studies the structures that can be seen only with magnification, like a microscope. a. Cytology is the study of cells. b. Histology is the study of tissues. 4. Macroscopic anatomy (or gross anatomy) is the study of structures visible to the naked eye. a. Study of the skeletal system b. Looking at an x-ray B. Physiology 1. Physiology focuses on the functions and processes of body structures. 2. Physiology is the study of how anatomical structures function. 3. Physiology deals with all the vital processes of life and is more complex than anatomy, with more subspecialties. a. Human physiology b. Animal physiology c. Cellular physiology d. Neurophysiology C. Putting It All Together 1. Anatomy focuses on structures and how body structures are put together. 2
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2. Physiology is the study of how these different structures work together to make the body function as a whole. 3. The design of the structure is often related to its function. 4. Human anatomy and physiology forms the foundation for all medical practice. a. Pathophysiology is the study of disease, or anything that negatively changes the body's normal function or structure. III. The Language A. Medical Terminology 1. Most terms are derived from Greek and Latin languages. 2. Each medical term has a basic structure on which to build, called a root word. 3. Prefixes and suffixes added to root words change or alter the meaning. B. Forming medical terms 1. If a suffix begins with a vowel, drop the vowel in the combining form. 2. When using prefixes, put the word parts in the order you say the definition; for example, before birth is prenatal. C. Abbreviations 1. The medical profession uses abbreviations extensively. 2. Abbreviations are useful in simplifying long, complicated terms for diseases, diagnostic procedures, and therapies. IV. The Metric System A. The metric system is the “mathematical language” of anatomy and physiology to measure weight, volume, and length. B. Two major systems of measurement used in the world today: 1. The U.S. Customary System (USCS) or English system a. Used in the United States b. Based on the British Imperial System c. Different designations for length, weight, and volume d. Difficult to use because there is no common base and no relationship between units 2. The metric system (Systéme International [SI])
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a. Used everywhere else, especially in health care, science, and pharmaceutical companies b. Based on the power (or multiples) of 10 c. Relationship between units V. The Language of Disease A. Disease is a condition in which the body fails to function normally. B. Eating habits, smoking, inherited traits, trauma, cancer, environmental factors, and aging can cause disease. C. Signs and Symptoms of Disease 1. Signs are definitive, objective (measurable), obvious indicators of wellness or an illness. a. Vital signs (signs that are essential to life) include pulse (heart rate), blood pressure, body temperature, respiratory rate, and pain. b. Lab values 2. Symptoms, like pain tolerance, are more subjective and difficult to measure. 3. A syndrome is a group of signs and symptoms that commonly occur with a specific disease. D. Other Disease Terms 1. Diagnosis is the identification of a disease determined by studying the patient’s signs, symptoms, history, and results of diagnostic tests. a. Chief complaint/concern (CC) is why the patient is seeking medical help. 2. Etiology is the cause of the disease. 3. Chronic conditions refer to a disease process that has existed for some time. 4. Acute conditions refer to a rapid onset of signs and symptoms. 5. Remission is a period of time when a chronic disease disappears. 6. Relapses are recurrences of the signs and symptoms of disease. 7. Exacerbation refers to an acute flare-up of signs and symptoms. 8. Mortality is the measure of the number of deaths attributed to a specific disease in a given population over a period of time. 9. Morbidity is the measure of the disabilities and extent of problems caused by an illness. 10. Endemic refers to a disease that is continually present within a specific population or region. 11. An epidemic is a disease that occurs suddenly in large numbers over a specific re4
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gion; a pandemic is a disease that spreads country- or worldwide. 12. Prognosis is the prediction of the outcome of a disease; a terminal disease has a prognosis of death. VI. Anatomy and Physiology Concepts You Will Encounter on Your Journey A. Homeostasis 1. Homeostasis is the physiologic process that monitors and maintains a stable internal environment or equilibrium. a. Heart rate and blood pressure must be maintained within a set point, or certain range. b. Homeostatic regulation refers to the adjustments made in the human organism to maintain homeostasis. 2. A negative feedback loop is a continuous feedback loop that senses the internal and external environments and makes adjustments. a. The feedback opposes the stimulus, bringing variable back to normal range. b. Example: The hypothalamus in the brain uses a negative feedback loop to control body temperature and maintain homeostasis. 3. Positive feedback increases the magnitude of a change instead of resisting change. a. This kind of process is also known as a vicious cycle. b. Not homeostasis c. An example of useful positive feedback is the recurrent contractions of the uterus during childbirth. VII. Metabolism A. On the cellular level, all humans require the process of metabolism to survive. 1. Metabolism refers to all the energy and material transformations that occur within living cells; it is subdivided into: a. Anabolism: the process by which simpler compounds are built up and used to manufacture materials for growth, repair, and reproduction. b. Catabolism: the process by which complex substances are broken down into simpler substances.
CLASSROOM ACTIVITIES 1. Make flash cards for students to learn to define medical terminology. Using the tables found in Chapter 1 of the text, print root words on blue paper, suffixes on red paper, and prefixes on yellow paper. Then tape one of each to the board to create a medical term and 5
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ask students to define it. Next, remove the suffix or prefix, replace it with another one, and ask them to define the new term and explain how it changed. 2. Name a common or familiar illness or disease, such as the common cold, allergic rhinitis, or diabetes. Have students give examples of signs and symptoms of that disease. Discuss how they know which examples are signs and which are symptoms. 3. Have students give examples of negative or positive feedback loops, or give them examples and have them decide whether the example is of a negative or positive feedback loop. 4.
Visit the Joint Commission web site and download the Official "Do Not Use" List of abbreviations. Discuss with students the various reasons different abbreviations are included on the list.
TEACHING STRATEGIES 1. Take every opportunity to use medical terminology, and have students dissect the word to determine what it means. 2. When medical terminology is used, have students learn the abbreviations that apply to that term. 3. Jeopardy! is a wonderful game to play to teach students medical terminology. Categories can include root words, prefixes, suffixes, medical terms, abbreviations, and medical definitions. 4.
During each class, post an unfamiliar medical term or terms for students to decipher. Turn it into a challenge, and award points to the student who figures out the term's meaning first, without the aid of a medical dictionary or other reference.
FACTOIDS 1. Many medical terms originate from the Latin language. Prior to the 1970s, students entering medical fields were encouraged to take Latin in high school. Latin is an extremely difficult language to learn, and few high schools even offer this subject today. 2. Hospitals regulate abbreviations used in medical documentation to maintain legality of the record. Each hospital has a standardized list of acceptable abbreviations, including things like HOB (head of bed), ROM (range of motion), HS (bedtime), and QID (four times a day).
ETHICAL DILEMMAS 1. It is virtually impossible to understand the meaning of every medical term—no matter how long you are in the profession—because you will always run into a new word you’ve not heard before. Have students discuss the ethical consequences of “guessing” what a term means when you don’t want to take the time to look the term up and learn exactly what it refers to.
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2. Hospitals are required to have a legally acceptable list of abbreviations that can be used in patient documentation. Ask students to explain what could happen if an abbreviation were used that others didn’t understand. Have students explain both the legal and ethical considerations of following this acceptable list of abbreviations.
ANSWERS TO TEST YOUR KNOWLEDGE Test Your Knowledge 1–1 Answers, p. 3 1. G 2. M 3. M 4. G 5. M Test Your Knowledge 1–2 Answers, p. 7 1. Acrocyanosis: blue extremities (condition of blue extremities) 2. Nephrologist: one who studies the kidneys 3. Cytomegaly: enlarged cells 4. Dermatitis: skin inflammation 5. Appendectomy: removal of the appendix 6. Removal of the stomach: gastrectomy 7. Disease of the bones: osteopathy 8. Electrical recording of the heart: electrocardiogram, or EKG or ECG 9. Inflammation of the joints: arthritis 10. One who studies the nervous system: neurologist 11. Abbreviation for patient not allowed to eat or drink: NPO 12. Abbreviation for giving a drug or treatment as needed: PRN Test Your Knowledge 1–3 Answers, p. 11 1. a. vital sign b. not a vital sign c. vital sign d. not a vital sign
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e. not a vital sign f. vital sign g. vital sign 2. c 3. a 4. b 5. d 6. a
ANSWERS TO THE CASE STUDY, P. 14 a.
What are his CCs and etiology? Chief complaints or concerns: shortness of breath (SOB), abdominal pain. Etiology: vehicular accident.
b.
Where exactly in the hospital was the patient taken? To the intensive care unit
c.
Describe the patient’s color, heart rate, and breathing. Patient’s extremities are bluish (acrocyanosis), his heart rate is fast (tachycardia), and he is having shortness of breath.
d.
What is the medical term for what the x-ray is showing? Cardiomegaly
e.
What future facial surgery will he need? A nose job or rhinoplasty
ANSWERS FOR REVIEW QUESTIONS, P. 15 Multiple Choice 1. c, 2. b, 3. b, 4. b, 5. d, 6. b, 7. c 8. d Fill in the Blank 1. arthroscope 2. Anatomy; physiology 3. liver; enlarged 4. vital 5. positive feedback (vicious cycle) Short Answer 1. A diagnosis is the process of pinpointing the underlying cause of symptoms and signs, whereas a prognosis is the predicted outcome of the disease.
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2. A phagocyte is a cell that ingests bacteria, viruses, and cellular debris (literally, a swallowing cell). 3. Negative feedback is a process in which the body attempts to reverse any change in physiology, bringing the variable back to “normal.” Positive feedback is a vicious cycle. Positive feedback enhances a change in physiology, usually making the situation worse. 4. There are many examples of homeostasis in the body. All physiological variables are controlled by homeostasis, including blood pressure, blood pH, blood sugar, body temperature, and hormone levels. All are regulated by negative feedback. For example, if blood pressure falls below normal levels, your body increases the heart rate and causes vasoconstriction. Increased heart rate and vasoconstriction increase blood pressure back toward normal. On the other hand, if blood pressure rises, the heart rate will decrease, and vasodilation will occur, decreasing blood pressure. 5. Jose has broken his leg. His symptoms may include pain, swelling, bruising, and decreased range of motion. The etiology is excessive mechanical forces that caused bone damage. His prognosis is that he will recover after rest and treatment. Treatment is immobilization for several weeks, rest, and perhaps surgery, depending on the severity of the break. 6.
An endemic refers to a disease that is continually present within a specific population or region. An epidemic is a disease that occurs suddenly in large numbers over a specific region; a pandemic is a disease that spreads country- or worldwide.
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Catabolism and anabolism are both functions of metabolism. Catabolism is the process by which complex substances are broken down into simpler substances, while anabolism is the process by which simpler compounds are built up and used to manufacture materials for growth, repair, and reproduction.
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Name __________________ CHAPTER 1—WORKSHEET Multiple Choice 1) The study of body structures is: A) anatomy. B) physiology. C) pathology. D) etiology. 2) The study of body functions is: A) anatomy. B) physiology. C) pathology. D) etiology. 3) The study of disease is: A) cytology. B) histology. C) physiology. D) pathology. 4) The physiological process that maintains a state of balance in the body is: A) homeostasis. B) idiopathic. C) communicable. D) pathological. Fill in the Blank For each of the following abbreviations, please write out the whole term. 5) PRN ________________________________________ 6) t.i.d. ________________________________________ 7) GI ________________________________________ 10
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8) BP __________________________________________ 9) DX __________________________________________ 10) CA _________________________________________ Worksheet – p. 1 of 2 Matching Please match the following word parts with the appropriate definition. 11)
_____ graphy
A.
Below
12)
_____ cardi/o
B.
Small
13)
_____ subˊ
C.
Tumor
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_____ hyperˊ
D.
Above normal
15)
_____ arthr/o
E.
Process of recording
16)
_____ˊlogist
F.
Tissue
17)
_____ bradý
G.
Specialist
18)
_____ microˊ
H.
Cell
19)
_____ˊmegaly
I.
Disease
20)
_____ˊoma
J.
Nose
21)
_____endoˊ
K.
Within
22)
_____ hist/o
L.
Slow
23)
_____ cyt/o
M.
Joint
24)
_____ rhin/o
N.
Heart
25)
_____ path/o
O.
Enlargement
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Worksheet – p. 2 of 2 ANSWER KEY Chapter 1—Worksheet 1) A 2) B 3) D 4) A 5) as needed 6) give three times a day 7) gastrointestinal 8) blood pressure 9) diagnosis 10) cancer 11) E 12) N 13) A 14) D 15) M 16) G 17) L 18) B 19) O 20) C 21) K 22) F 23) H 24) J 25) I 12
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Name _________________ LABELING ACTIVITY INSTRUCTIONS: Please label the arteries or common pulse points in the following diagram.
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LABELING ACTIVITY ANSWER KEY
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Chapter 2 THE HUMAN BODY: READING THE MAP LEARNING OUTCOMES List and describe the various body positions. Define the body planes and associated directional terms. Locate and describe the body cavities and their respective organs. List and describe the anatomical divisions of the abdominal region. Identify and locate the various body regions.
MULTIMEDIA FOUND ON THE POWERPOINT LECTURE OUTLINE
1. Fowler’s Positioning Video (slide 25) 2. Lateral Positioning Video (slide 26) 3. Dorsal Positioning Video (slide 27) 4. Prone Positioning Video (slide 28) 5. Lithotomy Positioning Video (slide 29) 6. Sims Positioning Video (slide 30) 7. Supine Positioning Video (slide 31) 8. Magnetic Resonance Imaging Video (slide 47) 9. Ultrasound Video (slide 48) 10. Radiologic Technology Video (slide 49) 11. Surgical Team Video (slide 75)
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Name __________________ LECTURE OUTLINE I. The Map of the Human Body A. Body Positions 1. To standardize the orientation for the study of anatomy, the anatomical position was developed: Stand erect, face forward, feet apart, arms at side, palms forward. 2. Supine position: laying face upward (sUPine = face UP) 3. Prone position: laying face downward (prONe = ON stomach) 4. Trendelenburg position: head lower than feet 5. Fowler’s position: seated with bed upright a. Semi-Fowler’s: seated at 45-degree angle b. High Fowler’s: seated at 90-degree angle 6. Additional positions include lithotomy, dorsal recumbent, Sims', knee-chest. B. Directional Terms 1. Depend on comparison with other body parts. 2. The point of reference is always from the patient’s point of view and is not dependent on which way the patient is facing you. 3. Terms usually come in pairs. a.Superior (cranial or cephalic): above, toward the head b. Inferior (caudal): below, toward the tail c. Anterior (ventral): toward the front, belly d. Posterior (dorsal): back, toward the back d. Medial: toward the midline f. Lateral: toward the side (away from the midline) g. Proximal: near the origin h. Distal: far from the origin i. External: near the outside of the body j. Internal: inside the body k. Superficial: near the surface
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l. Deep: away from the body's surface m. Central: near center of body (torso, head) n. Peripheral: near edges of body (extremities) C. Body Planes 1. A plane is an imaginary line drawn through the body or organ to separate it into specific sections. 2. Transverse or horizontal plane: Divides body into superior and inferior sections; also called cross-sectioning the body. 2. Sagittal plane: Divides body into right and left halves. 3. Frontal or coronal plane: Divides body into anterior (ventral) and posterior (dorsal) parts. 4. Median or midsagittal plane: Divides body into right and left halves.
D. Body Cavities 1. Anterior (ventral) cavity a. Divided by the diaphragm b. Thoracic cavity i. The thoracic cavity is superior to the diaphragm. ii. Contains heart, lungs, blood vessels. c. Abdominopelvic cavity: inferior to diaphragm i. Abdominal cavity a. Superior to imaginary line at pelvis b. Contains abdominal organs: stomach, intestines, liver, gallbladder, pancreas, and spleen. ii. Pelvic cavity a. Inferior to imaginary line at pelvis b. Contains pelvic organs such as the urinary bladder, reproductive system, rectum, and anus. 2. Posterior (dorsal) cavity a. Cranial cavity houses the brain. 3
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b. Spinal cavity (vertebral cavity) houses the spinal cord. 3. Many smaller cavities throughout the body, including the nasal, oral (buccal), and orbital cavities E. Body Regions 1. The abdominal region is divided into nine quadrants: a. Epigastric is superior to the umbilical region. b. The right and left hypochondriac are lateral to the epigastric. c. Umbilical region is located in the center, over the umbilicus. d. The right and left lumbar regions are located on either side of the umbilical region. e. The hypogastric region lies inferior to the umbilical area. f. The left and right iliac regions are located on either side of the hypogastric region. 2. It is simpler to divide the abdominal region into four quadrants, with the center line of the inferior/superior and left/right division being the umbilicus; quadrants are generally abbreviated. 1. Right lower quadrant (RLQ): appendix 2. Right upper quadrant (RUQ): liver, gallbladder 3. Left lower quadrant (LLQ): rectum 4. Left upper quadrant (LUQ): spleen 5. Midline area: aorta, pancreas, small intestine, bladder, spine CLASSROOM ACTIVITIES 1. Have students demonstrate various body positions by calling out the different positions and having students move to demonstrate them. 2. Play “Go to the Head of the Class.” Have all students start in the back of the classroom. Every time they answer a question correctly, they can move one seat forward until eventually they reach the head of the class. Rewards can be extra credit points, food, or privileges. 3. Play “Pin the Tail on the Anatomy.” Have students look for the body part based only on the technical name, or have blindfolded students directed to the point on the “body” by other students using only directional terms. TEACHING STRATEGIES
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1. Give students the names of organs, and ask them to identify in which body cavity the organs would be located. 2. The classic board game “Operation” can be a wonderful teaching tool for body cavities, organs, and anatomical divisions. Play a game where students must answer questions related to the chapter to win a chance to remove one of the “organs” in the game board. Questions should include things like “What is that organ called in real life?” or “What is the name for the body cavity where that organ is located?” If they successfully remove the organ without making the buzzer go off, they get to draw a card that awards them “money.” At the end of the game, they can use the money they’ve earned to buy rewards like extra credit points. FACTOIDS 1. Species with a vertebral column are classified as vertebrates and include fish, amphibians, reptiles, birds, and mammals. The various planes apply to veterinary medicine as well, and add the term “rostral” to refer to the direction toward the nose. Dorsal and ventral describe the sides closest to the sky and closest to the ground, respectively, in animals. The terms anterior and posterior are not necessarily the same as ventral and dorsal in fourlegged animals or invertebrates like lobsters. 2. A sagittal plane divides the body into right and left, but does not have to run down the center of the body—it can divide the body at any point. If the plane does run down the center of the body, dividing the body in half, it is a midsagittal plane. 3. Ipsilateral means on the same side, whereas contralateral means on the opposite side. ETHICAL DILEMMAS 1. Imagine that the doctor told you to surgically prepare the left hypochondriac region of the abdomen for surgery, and you didn’t know where that region was located. Ask students how they would go about finding out where that area was located. Ask them to discuss the ethics of “guessing” the location and potential consequences. 2. What obligation do you have to your patient to understand the information provided in this chapter? What consequences could occur if you fail to meet your obligation? ANSWERS TO TEST YOUR KNOWLEDGE Test Your Knowledge 2–1 Answers, p. 23 1. Person should be standing face forward, palms out as in Figure 2-1. 2. Best body position for following circumstances: a. Getting a back massage: prone b. Eating in a hospital bed: Fowler’s c. Watching television in bed: Fowler’s
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d. Watching the stars at night: supine 3. Give the opposite directional term: a. Superior: inferior b. Posterior: anterior c. Caudal: cephalic or cranial d. Ventral: dorsal e. Distal: proximal f. External: internal g. Superficial: deep h. Peripheral: central i. Medial: lateral 4. superficial 5. proximal; distal 6. superior 7. peripheral or pedal 8. central cyanosis Test Your Knowledge 2–2 Answers, p. 26 1. transverse or horizontal 2. anterior or ventral; posterior or dorsal 3. midsagittal 4. Identify the major body cavity in which each of the following organs is located: a. Heart: thoracic or pericardial b. Spinal cord: spinal or vertebral c. Stomach: abdominal or peritoneal d. Lungs: thoracic or pleural e. Reproductive organs: pelvic f. Brain: cranial 5. nervous 6
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6. magnetic Test Your Knowledge 2–3 Answers, p. 32 1. oral or buccal 2. axillary 3. umbilical 4. lumbar 5. patellar 6. spleen or liver 7. sternal ANSWERS TO CASE STUDY, P. 33 a. right knee b. center of the chest (breastbone area) c. left arm d. no stomach pain e. in front of elbow f. feet ANSWERS TO REVIEW QUESTIONS, P. 37 Multiple Choice 1. a, 2. d, 3. d, 4. d, 5. a, 6. d Fill in the Blank 1. anatomical 2. supine 3. inferior; superior 4. brain 5. peripheral or acrocyanosis 6. midsagittal
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Short Answers 1. The organs found in the abdominal cavity are the liver, stomach, pancreas, spleen, gallbladder, small intestine, and part of the large intestine. 2. In the prone position, a person is laying face downward. In the supine position, a person is laying face upward. In the Trendelenberg, a person's head is lower than the person's feet. In the Sims' position, a person is lying on the left side, with the left hip and lower extremity straight and the right hip and right knee bent. In the Fowler’s position, a person is sitting up at a 45- to 60-degree angle. 3. There are three superior regions in the abdominal cavity. The medial superior region is the epigastric (above the stomach) region. The lateral superior regions are the hypochondriac (under the ribs) regions. Inferior to those three regions are two lateral regions—the lumbar regions—and a medial region, the umbilical region. The three most inferior regions are two lateral regions—the iliac regions—and one medial region, the hypogastric (under the stomach) region.
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CHAPTER 2—WORKSHEET Multiple Choice 1) In this position, a patient is lying on the back, face upward. A) Prone B) Supine C) Trendelenburg D) Fowler’s 2) In this position, a patient is lying on the stomach, face downward. A) Anatomical B) Trendelenburg C) Prone D) Supine 3) In this position, a patient is lying with the head of the bed lower than the feet. A) Trendelenburg B) Prone C) Fowler’s D) Anatomical 4) A patient is standing erect, with face forward, feet parallel, arms hanging to the side, and palms facing forward. In which position is this patient? A) Supine B) Anatomical C) Fowler’s D) Prone 5) Which of the following would be found in the midline area of the abdomen? A) Liver B) Aorta C) Appendix D) Ureter
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Fill in the Blank 6) The _____ plane divides the body into left and right portions. 7) The _____ plane divides the body into anterior and posterior parts. 8) Another name for the midsagittal plane is the _____ plane. 9) The _____ plane divides the body into superior and inferior parts. 10) The cranial and spinal cavities are both part of the larger _____ cavity. 11) The thoracic and abdominal cavities are part of the larger _____ cavity. Worksheet—p. 1 of 2
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Matching Please match the following terms with the correct definition. 12) _____ Sternal
A. Foot region
13) _____ Pedal
B. Neck region
14) _____ Occipital
C. Cheek region
15) _____ Axillary
D. Breastbone region
16) _____ Cervical
E. Finger region
17) _____ Epigastric
F. Chest region
18) _____ Thoracic
G. Nose region
19) _____ Gluteal
H. Posterior head region
20) _____ Lumbar
I. Buttock region
21) _____ Oral
J. Superior central portion of the abdomen
22) _____ Buccal
K. Front of the elbow
23) _____ Antecubital
L. Low back region
24) _____ Digital
M. Mouth region
25) _____ Nasal
N. Armpit region
Short Answer/Essay 26. List three organs that might be found in the abdominal cavity. _________________________________________________________ _________________________________________________________ _________________________________________________________ 27. Give one example of an organ found in the thoracic cavity. _________________________________________________________ _________________________________________________________ _________________________________________________________ Worksheet—p. 2 of 2
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ANSWER KEY Chapter 2—Worksheet 1) B 2) C 3) A 4) B 5) B 6) sagittal 7) frontal/coronal 8) median 9) horizontal/transverse 10) dorsal 11) ventral 12) D 13) A 14) H 15) N 16) B 17) J 18) F 19) I 20) L 21) M 22) C 23) K 24) E 25) G 26) Answers will vary, but may include stomach, intestines, liver, kidneys, and bladder. 12
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27) Answers will vary, but may include heart, lungs, and esophagus.
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Name __________________ LABELING ACTIVITY #1 INSTRUCTIONS: Please label the cavities in the following diagram.
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LABELING ACTIVITY #1 ANSWER KEY
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LABELING ACTIVITY #2 INSTRUCTIONS: Please label the following regions.
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LABELING ACTIVITY #2 ANSWER KEY
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Chapter 3 BIOCHEMISTRY: THE BASIC INGREDIENTS OF LIFE LEARNING OUTCOMES Differentiate between atoms, elements, and ions. Define acids, bases, and pH, and their roles in the body. Describe molecular bonding. Discuss the biological importance of water. Describe the properties of a solution. Distinguish among the types of biological molecules. Explain metabolism. Explain the role of enzymes in physiology. Explain cellular respiration.
MULTIMEDIA FOUND ON THE POWERPOINT LECTURE OUTLINE 1. Carbohydrates Animation (slide 56) 2. Lipids Animation (slide 65) 3. Proteins Animation (slide 71) 4. DNA Animation (slide 74) 5. Biochemists Video (slide 94)
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Copyright © 2016 Pearson Education, Inc.
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LECTURE OUTLINE I. Biochemistry A. Atoms, Elements, and Ions 1. Element a. Smallest unit of matter b. Retains chemical properties; cannot be broken into smaller pieces by chemical techniques. c. Abbreviated using first two letters of technical name d. Trace elements: elements the body needs in small amounts 2. Molecule a. Two or more elements joined together b. Form compounds when two or more molecules are joined together. 3. Atoms a. Smallest particles of elements that still maintain the element's characteristics b. Nucleus contains: i.. Protons: positively charged particles ii.. Neutrons: neutral or noncharged particles c.. Electrons: negatively charged particles that circle nucleus 4. Ions a. Atoms that gain or lose electrons b. Polar: charged c. Gain electron, negative charge. d. Lose electron, positive charge. e. Electrolytes: charged ions found within the body that are physiologically important. Examples include sodium, calcium, magnesium, hydrogen phosphate, and bicarbonate. B. Acids and Bases 1. Acid: a chemical substance that can release hydrogen ions 2. Base: a chemical substance that can accept hydrogen ions
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3. pH: based on concentration of hydrogen ions 4. Measures relative strength of acids and bases. 5. pH < 7 is acid; pH = 0 is neutral; pH > 7 is basic (alkaline). 6. Strong acids and bases are harmful to living tissue. 7. Acid/base balance is carefully regulated primarily by the renal and respiratory systems. C. Molecular Bonding 1. Elements bound together to form molecules 2. Three types of bonds: a. Ionic bond: One atom gains electrons, the other loses them. Molecule is polar. b. Covalent bond: Atoms share electrons equally. Nonpolar. c. Polar covalent bond: Atoms share electrons unequally. Polar. D. Water 1. Chief liquid in biological systems 2. Polar covalent—unique characteristics a. Molecules classified based on relationship to water i. Hydrophilic: Will mix with water; literally “water loving.” ii. Hydrophobic: Will not mix with water; literally “water fearing.” b. Hydrogen bond i. Weak bond between hydrogen on one molecule and oxygen on another ii. Increased heat capacity; water heats up and cools off more slowly than air. E. Solutions 1. One substance dissolved in another is called a solution. 2. Solute: what’s dissolved 3. Solvent: the dissolver 4. Concentration: amount of solute in solution 5. Some solutions, such as normal saline, act as diluents (fillers, thinners). F. Biological Molecules
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1. Molecules found in living systems 2. Contain mainly carbon, hydrogen, and smaller amounts of oxygen, nitrogen, phosphorous; four classes include carbohydrates, lipids, proteins, and nucleic acids. 3. Carbohydrates a. Two hydrogens and one oxygen for each carbon (CH2O) b. Used mainly for energy storage (sugars and starches) c. Hydrophilic d. Classification i. Monosaccharides: simple sugars, 5–6 carbons; example: glucose ii. Disaccharides: two monosaccharides bound together; example: sucrose iii. Polysaccharides: chain of monosaccharides; starches; glycogen stored in the liver for energy 2. Lipids a. Two hydrogens for every carbon, very little oxygen b. Hydrophobic c. Used for energy storage, communication, protection d. Classification i. Fats and oils: glycerol and three fatty acid chains; familiar ii. Waxes: fatty acid chains and alcohol; most hydrophobic substance in body iii. Phospholipid: phosphate “head” hydrophilic; fatty acid “tails” hydrophobic; in cell membrane iv. Steroids: carbon atoms that are arranged in rings; used for communication between cells 3. Proteins a. Long chains of amino acids b. Always recognizable by the nitrogen atoms in the backbone of the molecule; peptide bond ties amino acids together. c. Very versatile in function d. Structure determined by amino acid order e. Denaturation: the process by which proteins lose their structure by application 4
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of an external stress or compound; this loss of structural integrity disrupts the ability of the proteins to perform their intended function. 4. Nucleic acids a. RNA and DNA b. Long chains of nucleotides c. Genetic molecules G. Metabolism 1. All the chemical reactions that take place in cells. 1. Anabolism: making large molecules from small ones; dehydration synthesis reactions occurs when water is removed and biological molecules join to form larger molecules. 2. Catabolism: breaking down large molecules into small; hydrolysis reactions occur when water is added to break apart large molecules. H. Enzymes: Making Reactions Happen 1. Most chemical reactions too slow to sustain cells 2. Enzymes speed up (catalyze) reactions. a. Protein molecules b. Not used up in reaction c. Molecules bind to enzyme and are carried through reaction. d. Characteristics i. Specificity: Only certain molecules can be carried by certain enzymes. ii. Competition: Molecules can compete for binding sites. iii. Inhibition: Enzyme can be blocked or prevented from working. iv. Saturation: Binding sites are full and molecules must wait for an empty enzyme before going through the reaction. I. Cellular Respiration and Adenosine Triphosphate (ATP): The Energy Molecule 1. Cellular respiration a. Uses glucose and oxygen. b. Makes carbon dioxide and water as waste. c. Makes lots of adenosine triphosphate (ATP). 5
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2. ATP a. Made of a base, a sugar, and (adenine) and three phosphates b. Remove one phosphate, release energy to use to run metabolism, and becomes ADP (adenosine diphosphate), which can pick up another phosphate to form ATP again. CLASSROOM ACTIVITIES 1. Assign students to the roles of enzymes and substrates. Have them act out enzyme activity. Demonstrate specificity, competition, inhibition, and saturation. 2. Provide students with descriptions of a number of molecules. Using the characteristics of biological molecules, ask students to classify the molecules. TEACHING STRATEGY 1. Many biological molecules and their characteristics are familiar to students. Use as many familiar examples as possible to illustrate the characteristics of different classes of biological molecules. FACTOID 1. Fat has nearly twice as many calories as carbohydrates or proteins. 2.
Fat in the human body is characterized as white fat and brown fat. White fat stores extra calories, while brown fat burns calories. Researchers are investigating ways to genetically reprogram white fat cells into brown fat cells, which one day might help in the treatment of such conditions as obesity and diabetes.
ETHICAL DILEMMA 1. Fat is needed by the body for many vital functions, such as a properly functioning immune system. However, it gets a very bad rap because of our diet-conscious society and a negative association with the word fat. This can cause some people to engage in unhealthy diets because they do not understand the need for fat intake and the various types of fats. Do you think a campaign should be launched to better explain this? ANSWERS TO TEST YOUR KNOWLEDGE Test Your Knowledge 3–1 Answers, p. 42 1. atom 2. ions 3. electrolytes 4. solute; solvent
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5. acid, decrease 6. diluents 7. 1% Test Your Knowledge 3–2 Answers, p. 45 1. Biological 2. amino acids 3. lipids 4. a. hydrophilic b. hydrophobic c. hydrophobic 5. energy Test Your Knowledge 3–3 Answers, p. 48 1. b 2. a 3. c 4. removed 5. ATP ANSWERS TO THE CASE STUDY, P. 49 A. Diuretics have side effects, including depletion of the electrolyte potassium. The chief side effect of low potassium is heart palpitations. B. Divya needs a potassium supplement and counseling concerning the dangerous practice of using diuretics to lose weight. C. Diuretics help rid the body of excess water and are therapeutic in a number of conditions, but are not to be used for weight loss, as this is not a true weight loss, and this practice has potentially dangerous side effects. Students who have researched diuretic use may describe hyperkalemia, or excess potassium, if using a potassium-sparing diuretic or hypokalemia (too little potassium) if using a thiazide diuretic. Some other side effects include dizziness, headache, muscle cramps, hyponatremia (low blood sodium), increased cholesterol, and rash. ANSWERS TO REVIEW QUESTIONS, PP. 49–50
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Multiple Choice 1. d, 2. b, 3. c, 4. c, 5. d Fill in the Blank 1. ions 2. polar covalent 3. electrolytes 4. water 5. metabolism 6. ATP Short Answer 1. Element: smallest unit that retains chemical characteristics; Atoms: smallest unit of element; Molecule: two or more elements bound together; Ion: atoms that gain or lose electrons 2. Ionic bond: One atom loses electrons while other gains them; polar. Covalent bond: Atoms share electrons equally; nonpolar. Polar covalent: Atoms share electrons unequally; polar. 3. Carbohydrates: Have two hydrogens and one oxygen for each carbon; used for energy storage; hydrophilic. Lipids: two or three hydrogens for every carbon, very little oxygen; used for energy storage and protection; hydrophobic. Proteins: long chain of amino acids, have nitrogen in molecule, very versatile. Nucleic acids: chains of nucleotides, genetic molecules. 4. Water is a polar covalent molecule with hydrogen bonding between molecules. It carries a charge. Its heat capacity is very high, causing water to heat up and cool down much more slowly than air. Polar molecules can mix with water, whereas nonpolar molecules cannot. Water is important to biological systems because it is the chief solvent in cells and tissues. 5. Enzymes are protein molecules that speed up biological reactions. The molecules bind to a site on the enzyme and are carried through the reaction. The enzyme is not used up during the reaction. Enzymes are very specific, speeding up only certain reactions. They can also be saturated (filled up), they can be inhibited (blocked), and molecules can compete for individual enzymes. 6.
For cells to carry out metabolism, they must have energy in the form of ATP, which is made via a complex series of reactions called cellular respiration. During cellular respiration, glucose combines with oxygen and is transformed in the mitochondria into adenosine triphosphate (ATP). The phosphate groups in ATP are held together by high-energy bonds. When a bond is broken, a high level of energy is released and can be used by the cells. When a bond is used, ATP becomes ADP (adenosine diphosphate), which has only
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two phosphate groups. The ADP is now able to pick up another phosphate and form a high-energy bond so energy is stored and the process can begin again.
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Name __________________ CHAPTER 3—WORKSHEET Multiple Choice 1) Which of the following is a characteristic of enzymes? A) Saturation B) Lipid C) Used up during reaction D) Nonspecific 2) Proteins are made of long chains of: A) nucleic acids. B) amino acids. C) lewis acids. D) citric acids. 3) This type of bond is nonpolar: A) Hydrogen B) Polar-covalent C) Ionic D) Covalent 4) _____ surround the atomic nucleus. A) Electrons B) Protons C) Neutrons D) Plutons 5) The point of cellular respiration is to make: A) water. B) glucose. C) ATP. D) metabolism. 10
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6) Molecules that have one oxygen for each carbon are called: A) proteins. B) carbohydrates. C) lipids. D) nucleic acids. 7) IV drugs are often mixed with __________ such as sterile water if they will be delivered to a patient over a long period of time. A) solutes B) lipids C) diluents D) bases Worksheet—p. 1 of 2
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Fill in the Blank 8) _____ occurs when a protein loses its structure and cannot perform its intended functions. 9) The measure of the acidity of solutions is _____. 10) Hydrophobic molecules will not _____ with water. 11) Glycogen, an energy storage molecule, is this type of molecule: _____. (Be specific.) 12) _____ molecules are important in the function of cell membranes. 13) _____ reactions are the chief reactions of catabolism. 14) The prevention of a substrate from binding to an enzyme binding site is called _____. 15) This class of biological molecule is always hydrophobic: _____ Matching 16. _____ Element
A. Fatty acid with alcohol
17. _____ Ion
B. Biologically important ion
18. _____ Monosaccharide
C. What is dissolved in solution
19. _____ Wax
D. Smallest unit that retains chemical characteristics
20. _____ Electrolyte
E. Solute dissolved in solvent
21. _____ Trace element
F. Sugar with 5–6 carbons
22. _____ Molecule
G. Biologically important element
23. _____ Polysaccharide
H. Charged atom or molecule
24. _____ Solute
I. Many sugars linked together
25. _____ Solution
J. Two or more elements bound together Worksheet—p. 2 of 2
ANSWER KEY Chapter 3—Worksheet 1) A 2) B 3) D 4) A
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5) C 6) B 7) C 8) Denaturation 9) pH 10) mix, dissolve 11) polysaccharide 12) Phospholipid 13) Hydrolysis 14) inhibition 15) lipids 16) D 17) H 18) F 19) A 20) B 21) G 22) J 23) I 24) C 25) E
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Chapter 4 THE CELLS: THE RAW MATERIALS AND BUILDING BLOCKS LEARNING OUTCOMES List and describe the various parts of a cell and explain their functions. Describe the types of active and passive transport within cells. Explain the process of cellular mitosis. Explain cellular respiration. Differentiate between bacteria, viruses, fungi, and protozoa. MULTIMEDIA FOUND ON THE POWERPOINT LECTURE OUTLINE 1. Cell Structure Video (slide 65) 2. Handwashing and Gloving Video (slide 104) 3. Lab Technicians Video (slide 105) 4. Cytotechnologist Video (slide 106)
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LECTURE OUTLINE I. Overview of Cells A. The cell is the building block of all living things. 1. Cells of a similar type form tissues that function to work together in an organ, while organs perform special functions to create a system.
2. Systems work together to form a functioning human body. B. Cells come in different sizes, shapes, and types. II. Cell Structure A. There are certain common traits that almost all cells share: nucleus, organelles, cytoplasm, and cell membrane. B. Cell Membrane 1. Also called the plasma membrane because it surrounds the cytoplasm of the cell a. A boundary that possesses a definite shape and actually holds the cell contents together, acting as a protein covering b. A cell membrane is a protective covering that allows material in and out of the cell. c. Cell membranes are selectively permeable (semipermeable) because they choose what gets in and out of the cell. d. 3/10,000,000 of an inch thick 2. Composed of lipids and proteins, with some carbohydrates a. Phospholipid bilayer keeps hydrophilic molecules (substances) from crossing while allowing hydrophobic molecules to enter. b. Contains abundant amounts of cholesterol. c. Proteins function as markers, channels, or carriers. 3. Transport Methods a. Passive transport requires no extra form of energy to complete; includes four types: i. Diffusion a. The most common form of passive transport; a substance of higher concentration travels to an area of lesser concentration. b. Necessary to transport oxygen from the lungs and into the blood c. Necessary to transport waste (carbon dioxide) from the blood to the lungs and eventually out into the air 2
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ii. Osmosis a. Movement of water across a semipermeable membrane when concentration gradient is present b. Water will move from an area of low solute concentration to an area of high solute concentration. c. The greater the concentration of solute, the greater the osmotic pressure, or pull, it exerts to bring in water. iii. Filtration a. Pressure is applied to force water and its dissolved materials across a membrane. b. Selectivity determined by size of holes or channels in membrane iv. Facilitated Diffusion (Carrier-Mediated Passive Transport) a. Substance moves down its concentration gradient with the help of a protein carrier molecule. i. Carrier is protein molecule with binding site. ii. Carrier is like enzyme system—specificity, saturation, inhibition, competition. b. Active transport requires some addition of energy to make it happen; it includes the following three types: i. Active transport pumps (Carrier-Mediated Active Transport) a. Use carrier molecule. b. “Pump” substance against concentration gradient c. Require the addition of energy in the form of adenosine triphosphate (ATP) to move a substance. ii. Endocytosis: The substances are moved into the cell using vesicles. Substance is too large to diffuse across the membrane. a. Phagocytosis is the name for this process if a solid particle is being transported. b. Pinocytosis is the name for this process if water is being transported. iii. Exocytosis is transport of things out of the cell in a vesicle. C. Cytoplasm a. A watery solution of organic and inorganic chemicals 3
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b. Internal environment of the cell D. Nucleus and Nucleolus 1. Nucleus is the “brain of the cell”; dictates the activities of the organelles in the cell. a. Has a double-walled nuclear membrane, with large pores allowing certain materials to pass in and out, while preventing other materials from entering. b. Chromatin is a material found in the nucleus, containing deoxyribonucleic acid (DNA). i. A combination of DNA and proteins ii. DNA contains the blueprints, specifications, for the creation of new cells; genes. iii. Chromatin will eventually form chromosomes, which contain genes. 2. Nucleolus a. Spherical body made up of dense fibers found within the nucleus b. Major function is to synthesize the ribonucleic acid (RNA) that forms ribosomes. E. Ribosomes 1. Found on the endoplasmic reticulum or floating around in the cytoplasm. 2. Made of RNA (ribonucleic acid) 3. Assists in making enzymes and other protein substances needed for cell repair and reproduction. F. Centrosomes 1. Contain centrioles that are involved in the division (reproduction) of the cell. 2. Centrioles are tubular in shape and usually found in pairs. G. Mitochondria 1. Tiny bean-shaped organelles 2. Act as the power plant to provide up to 95% of the body’s energy needs for cellular repair, movement, and reproduction. 3. If a cell needs more power, it increases the number of mitochondria in the cell. H. Endoplasmic Reticulum 1. A series of channels set up in the cytoplasms that are formed from folded membranes
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2. Rough endoplasmic reticulum has a sandpaper-like surface, with ribosomes on the surface; responsible for synthesis of protein. 3. Smooth endoplasmic reticulum has no ribosomes and appears smooth; synthesizes lipids and steroids. I. Golgi Apparatus 1. Looks like a bunch of flattened membranous sacs. 2. Processes and stores proteins, makes vesicles. J. Lysosomes 1. Vesicles containing powerful hydrolytic enzymes that take care of cleaning up intracellular debris and other waste 2. Destroy harmful bacteria by participating in the process of phagocytosis to maintain health. K. Other Interesting Parts 1. The cytoskeleton is a network of microtubules and interconnected filaments that provide shape to the cell and mobility to the cell and its contents. 2. Flagella are whip-shaped tails that move some cells, like sperm, to other locations. 3. Cilia are short, microscopic, hairlike projections located on the outer surface of some cells. They move particles using a wavelike motion. L. Applied Science: Cell Energy and ATP 1. During cellular respiration, glucose is combined with oxygen and is transformed in the mitochondria into ATP. a. Glucose is "burned" in the presence of oxygen, making water, carbon dioxide, and lots of energy. b. Carbon dioxide and water are made as waste products. 2. ATP is made up of a base, a sugar, and three (hence, triphosphate) phosphate groups. a. The phosphate groups are held together by high-energy bonds. When a bond is broken, a high level of energy is released. Energy in this form can be used by the cells. M. Mitosis 1. Cellular reproduction is the process of making a new cell. 2. Also known as cell division 3. Cells can only come from other cells and make identical copies of themselves (asexual reproduction).
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4. Eukaryotic cells make up the human body: a. Contain a nucleus, cellular organelles, and usually several chromosomes in the nucleus. b. All the chromosomes must be copied before the cell can divide; 46 in humans. c. Reproduce asexually through mitosis N. The Cell Cycle 1. Apoptosis is the death of a body cell; each one has a different life span. 2. Interphase—about 90% of the cell’s life. Cell is making DNA and organelles and getting ready to reproduce. 3. Mitotic phase is when the nucleus and cytoplasm divide. a. Mitosis is the division of nuclear material. b. Cytokinesis is the division of cytoplasm and organelles. 4. Asexual division in cells: mitosis a. Involves copying all the chromosomes (46) and dividing them equally between the new cells. 5. The Phases of Mitosis a. Prophase: Nucleus disappears; chromosomes become visible, spindle forms. b. Metaphase: Chromosomes line up in center of cell. c. Anaphase: Chromosomes split and pull away. d. Telophase: Nucleus reappears, chromosomes become invisible, spindle disappears. i. Cytokinesis occurs, splitting cytoplasm and cell membrane after telophase of mitosis. ii. Results in two identical daughter cells. 6. Mitosis in Your Body a. Growth of bone, for example b. Tissue replacement of red blood cells, for example c. Meiosis (sexual reproduction) is different; sperm and egg require only half the number of chromosomes as other cells. III. Microorganisms A. Bacteria 1. Prokaryotic cells have no nucleus, few organelles. 6
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2. Pathogens are bacteria that produce disease. 3. Normal flora live within us and are harmless and sometimes essential for life; certain bacteria in the intestines help to digest food, and some help to synthesize vitamin K, which we need for blood clotting. B. Viruses 1. Infectious particles that have a core containing genetic material that is surrounded with a protective protein coat called a capsid. 2. Cannot grow, eat, or reproduce by themselves. They must enter another host cell and hijack that cell to grow and reproduce. 3. Do not respond to antibiotics. 4. Can stay dormant in the body and become active later in life. C. Fungi 1. Fungi, the plural form of fungus, can be a one-cell or multicelled organism. 2. Plantlike organisms with tiny filaments, called mycelia, which travel out from the cell to find and then absorb nutrients. 3. Fungi spread through the release of spores. 4. Noninfectious fungi, such as mushrooms, exist. 5. Examples of fungal infections include athlete’s foot and thrush (candidiasis). D. Protozoa 1. Protozoa are one-celled animal-like organisms that can be found in water and soil. 2. Disease caused by these microorganism can result from swallowing them or from being bitten by insects that carry them in their bodies. E. Prions 1. Abnormal pathogenic agents that cause an abnormal folding of specific normal cellular proteins 2. Affected tissue is full of microscopic holes, causing the tissue to appear spongy. 3. Typically found in the brain; causative agent in certain rare, fatal brain diseases like Creutzfeldt-Jakob Disease (CJD) CLASSROOM ACTIVITIES 1. Have students view cells in a microscope and discuss what they see, along with the function of the organelles.
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2. Discuss the difference in treatment for bacteria, viruses, fungi, protozoa, and prions. Have students discuss different diseases caused by each of these microorganisms. Why do human prion diseases prove to be fatal? TEACHING STRATEGIES 1. To make a cell come alive, so that students can visualize and better understand its function, have students “play the role” of organelles. Several students can join hands and form a circle representing the cell membrane. Other students can carry out active transport or passive transport through the cell membrane, which will also demonstrate selective permeability of the cell wall. 2. Provide students with different cell functions and have them relate which organelle performs this function. 3.
Have students work in teams to make three dimensional models of a cell using modelling clay, Play-Doh, or food (gelatin, candy).
FACTOIDS 1. Aristotle (384–322 B.C.) was known for his experimental approach and numerous dissections. He was drawn to animal classification to discover aspects of connection between the soul and the human body. Some of his animal classifications still stand today. One of his famous thoughts is a foreshadowing of Mendelian genetic concepts. 2. The microscope opened up new doors in the field of biology, by allowing scientists to gaze into a new world: the cellular world. Galileo is credited with the invention of the microscope. Two of the main pioneers in microscope usage were Athanasius Kircher and Antonie von Leeuwenhoek. 3.
Cells in the human body are in a constant state of flux as old cells die and new cells form. Some cells, like the epithelial cells lining the stomach, last 5 days while others, like red blood cells, last about 120 days. Few cells in the body are actually as old as a person's biological age. However, a research team from the Karolinska Institute in Stockholm has discovered that cells in the visual cortex of the brain are in fact the same age as a person.
ETHICAL DILEMMAS 1. DNA can be very helpful in solving crimes. For that reason, some have suggested that everyone’s DNA be collected as soon as they are born and stored in a directory. In this manner, when a crime is committed or a crisis like 9/11 occurs, everyone’s DNA will already be in the database for comparison. Is this something we should do? 2. With advances in medicine, many diseases can be diagnosed based solely on DNA. Should a pregnancy be aborted if the fetus is known to carry a fatal disease? What if a person will eventually contract a disease like breast cancer or Huntington’s? Should insurance companies have access to DNA results, perhaps raising the cost of life insurance or health insurance if it turns out that a person’s DNA results show the likelihood of contracting a disease? Copyright © 2016 Pearson Education, Inc. 8
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3.
Is it ethical to use investigational medical interventions, or treatments that have not undergone rigorous testing and evaluation that prove their safety and efficacy, on human patients during a widespread outbreak of a virus, such as Ebola? Why or why not? If used, what ethical criteria should guide the use of such interventions?
ANSWERS TO TEST YOUR KNOWLEDGE Test Your Knowledge 4–1 Answers, p. 60 1. diffusion 2. lower; higher 3. filtration 4. diffusion 5. facilitated diffusion 6. Tell whether the following processes are active or passive: a. active b. passive c. passive d. active e. passive f. passive Test Your Knowledge 4–2 Answers, p. 64 1. What organelle is described in each of the following statements? a. nucleus b. endoplasmic reticulum c. mitochondria d. Golgi bodies or Golgi apparatus e. flagella f. nucleus g. lysosomes h. cilia 9
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Test Your Knowledge 4–3 Answers p. 67 1. b 2. a 3. c 4. d 5. d
ANSWERS TO CASE STUDY, P. 72 a. protozoa b. fungus c. virus d. bacteria ANSWERS TO REVIEW QUESTIONS, P. 81 Multiple Choice 1. d, 2. b, 3. b, 4. d, 5. d Matching nucleus, d; cell membrane, c; Golgi Apparatus, b; mitochondria, a; cytoplasm, e; lysosome, f. Short Answer 1. The four methods of passive transport are diffusion, osmosis, facilitated diffusion, and filtration. Diffusion: Solute moves from high concentration to low concentration; osmosis: Water moves from area of low solute concentration to area of high solute concentration; facilitated diffusion: Molecule moves from high to low concentration with help of carrier protein; filtration: Pressure forces water and dissolved substances through a membrane. 2. Viruses need cells because viruses to do not have organelles, so they cannot reproduce or perform any other cell functions without hijacking our cells.
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3. Passive transport does not need ATP, or cellular energy. For a cell to use active transport, it must spend ATP. 4. During cellular respiration, glucose is broken down. Oxygen is needed to make ATP. Water and carbon dioxide are given off, and many molecules of ATP are made. 5. Bacteria are cells without a true nucleus or organelles. Viruses are not even cells; they have a nucleic acid core and a protein coat. They cannot reproduce on their own. Fungi are plant-like organisms that may be multicellular or unicellular. They reproduce using spores. Protozoa are animal-like cells that are found in soil and water. 6.
Prions are abnormal pathogenic agents that cause an abnormal folding of specific normal cellular proteins. Tissue that is affected by prions is full of microscopic holes, causing the tissue to exhibit a spongy architecture. Prions have been recognized as the causative agent in certain rare, fatal brain diseases that exhibit neuronal loss and brain inflammation. One example is Creutzfeldt-Jakob Disease (CJD).
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Name __________________ CHAPTER 4—WORKSHEET Matching Please match the following types of cell membrane transport with the appropriate description. 1) _____ Diffusion 2) _____ Osmosis 3) _____ Filtration 4) _____ Exocytosis 5) _____ Active transport pumps 6) _____ Facilitated diffusion
A. Movement of water across a semipermeable membrane from areas of low solute concentration to high solute concentration B. A special kind of diffusion that uses a carrier protein C. Carriers that force substances into areas where they are already highly concentrated D. Movement of substances from areas of high to low concentration E. A cell surrounds a substance and draws it outside. F. Pressure is used to force water and dissolved substances across a membrane; small particles pass through, and large particles do not.
Please match the following organelles with the appropriate description.
7) _____ Nucleus
A. Manufacture proteins
8) _____ Golgi apparatus
B. Network of microtubules and filaments
9) _____ Ribosomes
C. A long whip-shaped tail attached to sperm cells
10) _____ Mitochondria 11) _____ Cell membrane
D. The chemical that makes our genes
12) _____ Centrosomes
E. The gel-like material inside the cell membrane
13) _____ Cytoskeleton
F. The “brain” of the cell
14) _____ Flagella 15) _____ Lysosomes
G. Determines which substances can enter the cell.
16) _____ DNA
H. Produce ATP.
17) _____ Cytoplasm
I. Are involved in cell division.
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J. Packages cell products for “shipping”
K. Contain powerful enzymes that can destroy bacteria and wastes.
Worksheet—p. 1 of 2
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True or False 18) T F Energy is required to complete passive transport. 19) T F Chromosomes are typically found in the Golgi apparatus. 20) T F Prions are single-celled organisms that cause disease. 21) T F Cells use exocytosis to swallow up solid particles like bacteria. Multiple Choice 22) These substances act like “carrier molecules” that facilitate chemical reactions: A) Enzymes B) ATP molecules C) DNA molecules D) Glucose 23) Which of the following is an example of passive transport? A) Exocytosis B) Phagocytosis C) Diffusion D) Pinocytosis Fill in the Blank 24) Cells convert glucose into ATP in a process called _________________. Short Answer/Essay 25. Explain why breathing is necessary for cellular respiration to occur. __________________________________________________________ __________________________________________________________ __________________________________________________________ Worksheet—p. 2 of 2
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ANSWER KEY Chapter 4—Worksheet 1) D 2) A 3) F 4) E 5) C 6) B 7) F 8) J 9) A 10) H 11) G 12) I 13) B 14) C 15) K 16) D 17) E 18) F 19) F 20) F 21) F 22) A 23) C 24) Cellular respiration 25) We inhale oxygen because it is necessary for the breakdown of glucose to produce ATP. Carbon dioxide develops as a waste product of ATP production. We exhale this carbon dioxide to remove it from the body. Copyright © 2016 Pearson Education, Inc. 15
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Name __________________ LABELING ACTIVITY INSTRUCTIONS: Please label the cell parts in the following diagram.
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LABELING ACTIVITY ANSWER KEY
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Chapter 5 TISSUES AND SYSTEMS: THE INSIDE STORY LEARNING OUTCOMES Explain the relationship between cells, tissues, organs, and organ systems. List and describe the four main types of tissue and variations within each type. Identify and describe the various body membranes. Differentiate the three main types of muscle tissue. Describe the main components of nervous tissue. List and describe the main functions of the body systems. MULTIMEDIA FOUND ON THE POWERPOINT LECTURE OUTLINE 1. Tissue Repair Animation (slide 44) 2. Body Systems Animation (slide 91) 3. Histotechnology Video (slide 92)
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LECTURE OUTLINE I. Overview of Tissues A. Cells are the basic building blocks of our bodies. B. Tissues are collections of cells united to perform a function. C. Organs are collections of tissues designed to perform particular functions. D. Organs that work together to perform major specific activities, often with the help of accessory structures, form what we call a system. A. Tissues Types 1. Tissue is a collection of similar cells that act together to perform a function. a. Four main types: epithelial, connective, muscle, nervous 2. Epithelial tissue a. Covers and lines b. Tightly packed cells forming a sheet c. Usually contains no blood vessels. d. Well innervated e. Has obvious top and bottom. f. Classified by shape a. Flat or scalelike cells—squamous b. Cube-shaped—cuboidal c. Column-like—columnar d. Stretchy and variably shaped—transitional e. Single layer—simple f. Multiple layer—stratified g. Looks like multiple layers but is single layer—pseudostratified. g. Membranes i. Membranes are sheetlike structures found throughout the body that perform special functions; can be classified as organs. ii. Epithelial membrane possesses a layer of epithelial tissue and a bottom layer of a specialized connective tissue. 2
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iii. Epithelial membranes can be classified into three general types: Cutaneous—skin; covers body surface. Serous—double-layered membrane; lines body cavities; visceral—covers organs surface; parietal—lines body cavity; potential space between layers. Mucous—lines tubes exposed to external environment; secretes mucus. 2. Connective Tissue a. The most common of the tissues, found scattered throughout the body more than any other form. b. Functions i. Mechanical support ii. Nutrient storage iii. Fluid storage iv. Defense c. Has extensive extracellular matrix that is nonliving. d. Classification based on types of cells and type of matrix: i. Connective tissue proper Loose—soft, weblike tissue (areolar) Adipose—fat Dense—tightly packed fibers in matrix ii. Cartilage—cells (chondrocytes) in holes (lacunae) in gelatinous matrix iii. Bone—cells (osteocytes) in holes in calcium and phosphate matrix iv. Blood and lymph—cells in liquid matrix e. Synovial membrane a. In joints (synovial fluid) b. Secretes lubrication fluid to reduce friction. 3. Muscle Tissue a. Provides the means for movement by and in the body. b. Has the ability to shorten itself (contractility). 3
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c. There are three types of muscle tissue: i. Skeletal muscle (striated muscle) Attached to bones; voluntary movement; controls size of an opening. Striated—has striped appearance. Cylindrical fibers (cells) with many nuclei Voluntary (consciously controlled) ii. Cardiac Muscle Walls of the heart Striated Branched, interlocking, uninucleate cells Involuntary iii. Smooth Muscle Walls of tubes and hollow organs (visceral) Not striated (smooth) Uninucleate cells, shorter and wider than skeletal muscle fibers Involuntary 4. Nervous Tissue a. Acts as rapid messenger for body. b. There are two types of nerve cells: i. Neurons—the conductors of information; include dendrites that receive sensory information. ii. Neuroglia (or glia)—support and connection cells. c. The membranes that cover the brain and spinal cord are called meninges. d. Many nerves have an insulating layer called the myelin sheath. B. Tissue Repair 1. Multistep process a. Wound fills with blood and inflammation occurs—redness, heat, swelling, pain. b. Clotting and scab formation 4
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c. Organization i. Fibroblasts lay down collagen and pull wound edges together. ii. Blood vessels form. iii. Pink, well-vascularized tissue fills in the space. d. Result a. Regeneration—replacement with original tissue b. Scarring—replacement with scar tissue; scar tissue does not function like regular tissue. 2. Regeneration ability depends on tissue type: a. Excellent—bone, blood, epithelium b. Fair—cartilage, skeletal muscle, dense connective tissue c. Terrible—nervous, cardiac muscle C. Organs 1. An organ is the result of two or more types of tissue organizing in such a way as to accomplish something that the tissues cannot do on their own. 2. The body cannot survive without organs known as vital organs. 3. Organs work as part of a system. D. Systems 1. A system is formed by organs that work together to accomplish something more complex than what a single organ can do on its own. 2. Each system is interrelated, the organs often depending on each other for the proper functioning of the body. 3. Skeletal System a. Functions of the skeletal system i. Provides support and structure to the body. ii. Protects organs. iii. Provides movement. iv. Stores a variety of minerals. v. Produces blood cells. 5
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b. The main components of the system are bones, joints, ligaments, and cartilage. 4. Muscular system a. Voluntary muscles i. Movement created by conscious thought, like scratching your nose ii. Skeletal muscles attached to your bones b. Involuntary muscles i. Perform without conscious thought. ii. Classified as smooth (visceral) muscle or cardiac muscle iii. Found in blood vessels, airways, and organs 5. Integumentary System a. The body’s first line of protection is the skin. b. Skin is one part of the integumentary system. c. Functions i. Temperature regulation (sweating, shivering, blood vessel diameter) ii. Sense of touch iii. Glands in the skin help to lubricate and waterproof your skin and inhibit the growth of unwanted bacteria. iv. Production of vitamin D when exposed to sunlight d. The main components include skin, hair, sweat glands, sebaceous glands, and nails. 6. Nervous System a. The main parts of the nervous system include the spinal cord, brain, peripheral nerves, and nerve cells. b. The three main functions of the nervous system are: i. Receiving sensations (sensory input) ii. Processing and interpreting messages iii. Acting on messages (motor output) c. The main components include the nerve cells (glial cells and neurons), the spinal cord with its spinal fluid, peripheral nerves, and the brain. 6
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7. Endocrine System a. The endocrine system acts as a control center for virtually all the body’s organs. b. Endocrine glands release chemicals called hormones that are circulated via the cardiovascular system, regulating the metabolic processes and utilizing metabolites for growth and production. c. The main components of the endocrine system are the hypothalamus, pineal, pituitary, thyroid, parathyroid, thymus, adrenal glands, pancreas, and gonads, plus a large variety of hormones 8. The Cardiovascular System a. Also called the circulatory system, this is the main transportation system to each cell of our body. b. Functions include transporting water, oxygen, and a variety of nutrients and other substances to the cells, and transporting waste products away from the cells. c. The main components are the heart, arteries, veins, capillaries, and blood. 9. The Respiratory System a. Functions i. Supplies the cells with oxygen and removes carbon dioxide. ii. Filters, warms, and moistens the air we breathe. iii. Mucous lining of the airway helps trap foreign particles and germs. iv. Maintains the proper acid–base balance. b. The main parts of this system include the pharynx, larynx, trachea, bronchial tubes, lungs, and alveoli. 10. The Lymphatic and Immune System a. Functions i. Responsible for helping to maintain proper fluid balance and protect from infection ii. Special structures, called lymph nodes, act as filters to capture unwanted infectious agents. iii. Specialized white blood cells, called lymphocytes, fight infection. b. Major parts of this system include lymph vessels, lymph ducts, lymph nodes, thymus gland, tonsils, and spleen. 11. Gastrointestinal, or Digestive, System 7
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a. Often called the gastrointestinal (GI) system, the digestive system mechanically and chemically breaks down raw material (food) into usable substances, which are absorbed and transported to cells. b. Functions i. Ingestion ii. Digestion (breakdown) iii. Absorption of nutrients iv. Solid waste removal c. The main parts of this system include the mouth, pharynx, esophagus, stomach, intestines, accessory organs, and anal canal. 12. Urinary System a. Functions i. Elimination of waste products, electrolytes, drugs, and other toxins ii. Fluid regulation iii. Blood pressure regulation iv. Regulation of red blood cells v. Electrolyte balance vi. pH balance b. The kidneys, ureters, urinary bladder, and urethra are all important parts of this system. 13. Reproductive System a1. Reproductive system is often combined with the urinary system to make the genitourinary system, or GU system. b. The purpose of this system is reproduction. c. The main female parts of this system include the ovaries, uterus, fallopian tubes, vagina, and vulva. d. For men, the main parts are the testes, epididymis, penis, urethra, and several accessory glands. CLASSROOM ACTIVITIES 1. Have students play “Name that body system.” Make a list of body organs, and pull one card at a time, asking students to name the organ system where it would be found. Exam8
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ples might include the stomach, bladder, brain, vertebrae, and gluteus maximus. This can be done in teams or individually. Students earn points that can be converted into bonus points or privileges. 2. List body parts and have students tell you whether they are cells, organs, tissues, membranes, or body systems. 3. Write a key to the tissues or a flowchart decision tree, listing characteristics of tissues and ways to distinguish one tissue from another. TEACHING STRATEGIES 1. Although this book discusses each system individually, this is an excellent chapter for helping students recognize that all the body systems are actually very dependent on one another. Explaining how the respiratory system affects the cardiovascular system, how anemias affect the respiratory system, the need for proper endocrine control to maximize functioning of the nervous system, and so forth can help them recognize the interrelationships among all the organ systems. 2. Connective tissue plays a vitally important role in most of the organ systems. Helping students recognize the different types of connective tissue and the role of each will help them better understand interplay that is more complex. 3. An Internet search on the keyword “histology” yields numerous websites that illustrate and explain the various types of cells and tissue. FACTOIDS 1. The first four types of tissues to arise from the fertilized egg in the developing zygote are the epithelial, connective, muscular, and nervous tissues. From that point onward, these four cells develop into the fetus, developing specialized functions and creating all the necessary components of a human being. 2. Histology is essentially microanatomy, or the study of microscopically small components of the human body. Robert Hooke first discovered the cell in 1665, and the word cell comes from cellula, Latin for small compartment. 3. Scientists have identified adult stem cells, or somatic stem cells, in many tissues and organs of the human body, including the brain, heart, liver, and blood. These cells are undifferentiated but have the capacity to differentiate, or specialize, to repair the tissue in which they are located. Researchers are exploring whether adult stem cells can also transdifferentiate, or differentiate into cells other than the type of cell from which they originate. Other research is exploring genetically modifying adult stem cells to reprogram them as other cell types. Such advances may one day be used in the treatment of various diseases such as macular degeneration, spinal cord injury, stroke, burns, heart disease, diabetes, osteoarthritis, and rheumatoid arthritis. ETHICAL DILEMMAS 9
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1. Organ transplantation is very common, but there are still some cultures that believe the body should remain intact. Is it ethically acceptable not to donate healthy organs? 2. Should organ donation be legally mandated to save lives? 3. It is possible to produce tissues in the lab. In the wrong hands, what kind of problems could this create? ANSWERS TO TEST YOUR KNOWLEDGE Test Your Knowledge 5–1 Answers, p. 80 1. c 2. b 3. a 4. c 5. b 6. d 7. c Test Your Knowledge 5–2 Answers, p. 84 1. b 2. b 3. a 4. d 5. b 6. c 7. d Test Your Knowledge 5–3 Answers, p. 97 List the correct system. 1. respiratory 2. urinary 3. skeletal 4. nervous and sensory system 5. immune and lymphatic 10
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6. cardiovascular 7. digestive or gastrointestinal 8. integumentary 9. reproductive ANSWERS FOR CASE STUDY, P. 98 This patient has a rapid heart rate, rapid respiration rate with shortness of breath, and bluish extremities. He has a history of smoking and diabetes and is moderately overweight. He does not have a fever. The patient is clearly having respiratory problems and perhaps cardiovascular problems. The diabetes is perhaps an endocrine problem. He should be referred to a cardiologist and a lung doctor (pulmonologists) right away to deal with his acute problems. A respiratory therapist will probably treat him. Eventually he might see an endocrinologist for his diabetes. He might eventually need to see an oncologist (cancer doctor) if it turns out that he has lung cancer from smoking. ANSWERS TO REVIEW QUESTIONS, P. 98 Multiple Choice 1. a, 2. b, 3. c, 4. b, 5. d, 6. b, 7. c Fill in the Blank 1. nervous 2. muscular or skeletal 3. connective 4. visceral 5. endocrine 6. skeletal Short Answer 1. In order from simplest to most complex: cells, tissues, organs, systems 2. Epithelium has no blood vessels, has a distinct top and bottom, and has no extracellular matrix. Connective tissue is often well vascularized, usually has no distinct top or bottom, and has an abundant extracellular matrix. 3. The different types of membranes include synovial, cutaneous, serous, and mucous. Synovial membranes are connective tissue membranes that line joint cavities and lubricate them. Cutaneous membranes are epithelial membranes with a layer of connective tissue that covers the body. Serous membranes are double-layered epithelial membranes that line 11
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body cavities and cover organs. There is a potential space between the layers. Mucous membranes are epithelial membranes that line body spaces that are exposed to the environment. These membranes secrete mucus. 4. The three types of muscle tissue are skeletal, cardiac, and smooth. Skeletal muscle is striated, voluntary muscle found attached to bones. Cardiac muscle is involuntary, striated muscle found in the wall of the heart. Smooth muscle is involuntary, unstriated muscle found in the walls of hollow organs. 5. Arthritis—skeletal system; Hepatitis—digestive system; Pneumonia—respiratory system; Osteoporosis—skeletal system; Urinary tract infection—urinary system 6. Because they have the ability for cell division, stem cells can serve as an internal repair system for certain tissues. Stem cells can be harvested from both adult and embryonic sources. Researchers are exploring the numerous opportunities for using stem cells to treat diseases and disorders. Numerous conditions may benefit from stem cell therapy (regenerative medicine). Some examples that students might list include traumatic brain injury, stroke, Alzheimer's disease, Parkinson's disease, spinal cord injury, myocardial infarction, muscular dystrophy, osteoarthritis, diabetes, and Crohn's disease.
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Name __________________ CHAPTER 5—WORKSHEET Multiple Choice 1) This type of tissue covers and lines most of the body: A) Connective B) Epithelial C) Nervous D) Muscle 2) This type of tissue holds things together and provides structure and support: A) Connective B) Epithelial C) Nervous D) Muscle 3) This type of tissue can shorten itself: A) Connective B) Epithelial C) Nervous D) Muscle 4) This type of tissue can send and receive messages: A) Connective B) Epithelial C) Nervous D) Muscle 5) This is a two-layered membrane that lines body cavities and has fluid between the layers: A) Mucous B) Cutaneous C) Serous 13
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D) Muscular 6) This type of membrane is found between the bones of a joint: A) Synovial B) Serous C) Mucous D) Cutaneous 7) This type of membrane is found lining all openings to the outside world (including organs of the digestive system and respiratory system): A) Synovial B) Mucous C) Serous D) Muscular Worksheet—p. 1 of 3 8) Which of the following is not made of connective tissue? A) Bone B) Blood C) Muscles D) Fat 9) The pancreas is a(n) ____________ and part of the _____________. A) tissue; urinary system B) organ; gastrointestinal system C) system; epithelial tissue D) organ; parietal membrane 10) Which body system helps maintain proper fluid balance and protects the body from infection? A) Respiratory B) Reproductive C) Lymphatic 14
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D) Cardiovascular Matching Please match each term with the best description. 11) _____ Meningitis 12) _____ Membrane 13) _____ Melanoma
A. A type of skin cancer with a very high mortality rate B. A cell that is tall and thin, like a column
14) _____ Squamous
C. An epithelium with more than one cell layer stacked on top of one another
15) _____ Cuboidal
D. A cell that is flat and irregularly shaped
16) _____ Columnar
E. The type of muscle that is found in the heart
17) _____ Simple 18) _____ Stratified 19) _____ Pseudostratified 20) _____ Smooth 21) _____ Cardiac 22) _____ Skeletal 23) _____ Voluntary 24) _____ Involuntary
F. The type of muscle found attached to the bones G. Inflammation of the membranes surrounding the brain and spinal cord H. An epithelium that looks like it has several layers, when it really does not I. A cell that is cube-shaped J. A type of muscle that is not under conscious control K. A sheetlike structure that has a specific function L. The type of muscle found in blood vessels and hollow organs M. An epithelium with only one cell layer N. A type of muscle that is consciously controlled Worksheet—p. 2 of 3
Short Answer/Essay 25. List the steps in tissue repair. __________________________________________________________ 15
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__________________________________________________________ __________________________________________________________ Worksheet—p. 3 of 3 ANSWER KEY Chapter 5—Worksheet 1) B 2) A 3) D 4) C 5) C 6) A 7) B 8) C 9) B 10) C 11) G 12) K 13) A 14) D 15) I 16) B 17) M 18) C 19) H 20) L 21) E 22) F 23) N 16
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24) J 25) Inflammation, clotting, scab formation, organization, scarring, or regeneration
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Name __________________ LABELING ACTIVITY INSTRUCTIONS: Please label the membranes and mucosa in the following diagram.
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LABELING ACTIVITY ANSWER KEY
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Colbert IRM, 3e Ch 06
Chapter 6 THE SKELETAL SYSTEM: THE FRAMEWORK LEARNING OUTCOMES Describe the functions of the skeletal system. Discuss the general classification of bone based on shape. Identify and describe the anatomy and physiology of bone. Describe the process of bone growth and repair. Discuss the process of bone healing and aging. Differentiate between bone, cartilage, joints, ligaments, and tendons. Locate and describe the various joints and types of movement of the body. Locate and describe the various bones within the axial and appendicular skeleton. List the specific bones contained within special regions of the body. Describe common disorders of the skeletal system. MULTIMEDIA FOUND ON THE POWERPOINT LECTURE OUTLINE 1. Hip Displacement Animation (slide 32) 2. Bone Healing Animation (slide 52) 3. Fractures Animation (slide 57) 4. Knee Displacement Animation (slide 70) 5. Classification of Joints Animation (slide 76) 6. Movement of the Joints Animation (slide 83) 7. Ankle Dorsiflexion/Extension Animation (slide 84) 8. Ankle Inflexion/Eversion Animation (slide 85) 9. Elbow Pronation/Supination Animation (slide 86) 10. Elbow Flexion/Extension Animation (slide 87) 11. Hand Opposition Animation (slide 88) 12. Humerus Adduction/Abduction Animation (slide 89) 13. Humerus Circumduction Animation (slide 90) 14. Humerus Rotation Animation (slide 91) 15. Wrist Circumduction Animation (slide 92) 1
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16. Wrist Flexion/Extension Animation (slide 93) 17. Osteoporosis Video (slide 128) 18. Arthritis Video (slide 129) 19. Radiologic Technology Video (slide 132)
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LECTURE OUTLINE I. Introduction A. Function 1. Provides support and allows us to move. 2. Bones (osseus tissue) protect the soft body parts, produce blood cells, and act as a storage unit for minerals and fat. 3. Human skeleton has 206 bones. II. System Overview: More than the "Bare Bones" About Bones A. General Bone Classification 1.
Composed of nonliving minerals such as calcium and phosphorous, but are alive.
2. The word skeleton comes from the Greek, meaning “dried-up body.” 3. Bones may be classified by their shape: a. Long bones—bones are longer than they are wide. b. Short bones—equal in width and length c. Flat bones—thinner and can be either flat or curved; sternum is an example. d. Irregular bones—odd in shape, and include the hipbone; vertebrae are an example. B. Basic Bone Anatomy 1. Periosteum a. Outer covering of tough, fibrous connective tissue b. Contains blood vessels, lymph vessels, and nerves. c. Acts as anchor points for ligaments and tendons. 2. Epiphysis and diaphysis a. Both ends of a long bone increase in size to form the epiphysis. b. The region running between two epiphyses is called the diaphysis. c. The diaphysis is hollow; called the medullary cavity, it acts as a storage area for the yellow bone marrow. i. Red marrow makes red blood cells. 3
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ii. Yellow marrow has a high fat content and can convert to red marrow in an emergency. C. Bone Tissue 1. Two types a. Compact bone i. Dense, hard tissue normally composing the shafts of long bones; found as the outer layer of the other bone types ii. Microscopic cylindrical shaped units called osteons, or haversian systems a. Mature bone cells (osteocytes) form concentric circles around a central canal (haversian canal) that contains blood vessels. b. The area around the osteocyte is filled with protein fibers, calcium, and other minerals. c. Osteons run parallel to each other with blood vessels connecting them through perforating canals. b. Spongy bone i. Arranged in bars and plates called trabeculae ii. Irregular holes between the trabeculae give the bone a spongy appearance. iii. Spongy bone is lined by endosteum, which has the same function and similar structure to periosteum. iv. Purposes: Make bones lighter in weight and provide space for red bone marrow. D. Surface Structure of Bones 1. Bone is not perfectly smooth. 2. Projections act as points of attachment for muscles, ligaments, or tendons. 3. Grooves and depressions act as pathways for nerves and blood vessels. 4. Projecting structures and depressions can work together as joining or articulation points to form joints, such as the ball-and-socket joint in your hip. E. Bone Growth 1. Ossification (osteogenesis): formation of bone in the body a. Bones grow longitudinally to lengthen. b. Bones grow wider and thicker to more efficiently support additional body 4
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weight and any other weight we support when we work or play. 2. Types of cells involved in bone formation and growth a. Osteoprogenitor cells: nonspecialized cells found in the periosteum, endosteum, and central canal of compact bones b. Osteoblasts are cells that actually form bones. c. Osteocytes are mature bone cells that were originally osteoblasts. d. Osteoclasts tear down bone material and help move calcium and phosphate into the blood. 3. Bone development and growth a. Bone development begins when you are an embryo through intramembranous and endochondral ossification. i. In intramembranous ossification, bone develops between two sheets composed of fibrous connective tissue. a. Cells from connective tissue turn into osteoblasts and form a matrix. b. Other osteoblasts create compact bone over the surface of the spongy bone. c. Once the matrix surrounds the osteoblasts, they become osteocytes. d. Skull bones and the clavicle are examples. b. Endochondral ossification occurs when shaped cartilage is replaced by bone. i. Periosteum surrounds the diaphysis of the cartilage model as the cartilage itself begins to break down. ii. Osteoblasts come into this region and create spongy bone; primary ossification center. iii. Osteoblasts begin to form compact bone under the periosteum. iv. Osteoclasts break down the spongy bone of the diaphysis to create the medullary cavity. v. Secondary ossification centers develop in the epiphyses. c. Epiphyseal Plate i. After you are born, the epiphysis of your long bones continues to grow. ii. A thin band of cartilage forms an epiphyseal plate (growth plate) between the primary and secondary ossification centers. iii. Growth stops when plate turns to bone—closure. 5
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iv. Controlled by hormones F. Bone Repair 1. Repair occurs through endochondral ossification a. To heal, bones must be: i. Touching (reduction). ii. Immobilized. 2. Stages of bone repair
3.
a.
Stage 1: Hematoma forms; inflammation.
b.
Stage 2: Soft callus formation (cartilage fills in spaces)
c.
Stage 3: Hard (bony) callus forms.
d.
Stage 4: Remodeling
Bone fractures
a. A hairline fracture looks like a piece of hair on the x-ray. It is a fine fracture that doesn’t completely break or displace the bone. b. Simple or closed fracture—a break with minimal displacement and no tear in the skin c. Spiral fracture—caused by a twisting motion to the bone d. Greenstick fractures are incomplete breaks often found in children . e. Comminuted fracture—when the bone fragments or splinters f. Compound or open fracture—when the bone protrudes through the skin, with the potential of infection from exposure G. Cartilage 1. Cartilage is a special form of dense connective tissue that can withstand a fair amount of flexing, tension, and pressure. 2. Location and functions a. Permanent cartilage: The flexible part of your nose and ears are cartilage. b. Makes a flexible connection between bones, as between the ribs and sternum, allowing chest flexion during deep breathing. c. Articular cartilage acts as a cushion between bones; articular cartilage is located on the ends of bones and acts as a shock absorber, preventing the ends from grinding together during movement. i. Bursa are small sacs at the ends of bones that contain synovial fluid. 6
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H. Joints and Ligaments 1. When two or more bones join, an articulation or joint is formed. 2. Many joints must be held together, yet still be movable, which is accomplished by special connective tissue called ligaments. 3. Tendons are cordlike structures that attach muscle to bone. 4. Joints can be classified by function or structure. a. Function i. Immobile ii. Move a little. iii. Move freely. b. Structure i. Fibrous: bones joined by short connective tissue strands ii. Cartilaginous: bones united by cartilage iii. Synovial: bones united by fluid filled joint cavity Gliding joints—flat, or slightly curved, platelike bones (wrists and ankles) Hinge joints—one bone is in the shape of a cylinder and the other a trough. They can either open or close (knees and elbows). Saddle joint—bone shaped just like a saddle and another bone similar to a horse’s back; rock up and down and side to side (thumb). Ellipsoidal joint (condyloid)—oval-shaped bone end fitting into an elliptical cavity in the other bone so there is movement from one plane to another but no rotation (fingers and toes) Pivot joint—turnstile movement; has a circular portion of one bone that spins inside a ring-shaped portion of the other (neck and forearm). Ball-and-socket joint—spherical articulation with a cup-shaped socket on the other bone (hip and shoulder) I. Movement classification 1. Flexion—decreasing the angle of joint 2. Extension—increasing angle of a joint 3. Plantar Flexion—pointing toes down 7
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4. Dorsiflexion—bending the foot up toward the body 5. Abduction—moving away from the body’s midline 6. Adduction—moving toward the midline of the body 7. Inversion—turning the foot inward toward other foot 8. Eversion—turning the foot outward away from opposing foot 9. Supination—turning hand palm up 10. Pronation—turning hand palm down 11. Protraction—drawing part forward 12. Retraction—drawing part backward 13. Circumduction—circular arm movement 14. Rotation—spinning on axis III. The Skeleton A. Two main divisions of the skeleton 1. Axial skeleton—bones of the thorax, spinal column, hyoid bone, bones of the middle ear, and skull. They protect the body organs and are composed of 80 bones. 2. Appendicular skeleton—these are the bones of your arms, legs, hips, and shoulders and are composed of 126 bones. a. The appendicular region consists of the arms and legs. b. Half the bones in the body are located in the hands and feet. c. Contains 216 bones. B. Special Regions of the Skeletal System 1. The Human Skull a. Many bones forming brain case and facial structures, oral cavity b. Contains fibrous connective tissue joints called suture lines that hold the bony plates of the skull together. 2. The Bony Thorax a. Bones of the chest form thoracic cage. b. Sternum (breastbone) has three parts: Manubrium is the superior portion; body is the largest, central portion; xiphoid process inferior portion. c. 12 pairs of rib: true ribs are pairs 1–7 (vertebrosternal); pairs 8–10 are false 8
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(vertebrocostal); pairs 11 and 12 are called floating ribs (no anterior attachment). 3. The Spinal Column a. Also called vertebral column, houses the spinal cord, the superhighway for information coming to and from the central nervous system. b. The individual bones or vertebrae are numbered and classified according to the body region where they are located. c. 7 cervical vertebrae in the neck area d. 12 thoracic vertebrae in the chest area e. 5 lumbar vertebrae in the waist area f. 5 sacral vertebra below the waist g. 3–5 small fused bones at the very end that form the coccyx 4. Upper and Lower Extremities a. Arms and legs are of similar construction: i. One large bone (humerus in the arms; femur in the legs) ii. Two smaller bones in the forelimb (radius and ulna in the arms; tibia and fibula in the legs) iii. Multiple bones (carpals in the wrist; tarsals in the ankle); followed by five single bones (metacarpals in the hand; metatarsals in the foot) iv. Digits made of multiple bones called phalanges v. Arms and legs are attached to the axial skeleton via the pectoral and pelvic girdles, respectively. b. Pectoral girdle consists of the clavicle and scapula. c. Pelvic girdle consists of the pelvic bones (ischium, ilium, and pubis). i. Pelvic girdle in women has greater angle and broader girdle (childbirth). IV. Common Disorders of the Skeletal System A. Aging affects the cartilage and bones; although a natural process, it can sometimes be slowed. 1. Composition of cartilage changes as we age, becoming more brittle and yellow due to calcification; this can lead to arthritis, an inflammatory process of the joints, reducing flexibility and decreasing range of motion. 2. Bone mass decreases with age. Beginning in our 50s, the breakdown of bone is greater than the buildup. a. Osteoporosis: light, weak, porous bones. More common in women, but can be diagnosed in men. 9
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b. Treatment and prevention of osteoporosis i. Even though bone loss is a natural aging process, it can be slowed by a healthy lifestyle. ii. Proper calcium intake during the formative years and through adulthood decreases the risk of osteoporosis. iii. Vitamin D is important because it allows the body to absorb ingested calcium from the digestive tract. iv. Exercise, especially weight-bearing, plays a vital role in developing and maintaining strong bones. v. Drink less coffee. vi. Quit smoking. vii. Medication
CLASSROOM ACTIVITIES 1. Have students stand up in class and point to or describe a bone. The next student in line has to name the bone, and then point to another one for the next student to name. Go around the room doing this until the first student names a bone. 2. Point to a joint in the body, and have students name the type and function of the bone. 3. Play "Simon Says" with the class, calling out movement classifications and having them do the proper movement. For example, “pronate your hand” or “abduct your left leg.” 4.
For the musically inclined, search the Internet to find numerous songs and videos that will help students remember the names and locations of bones, or have students make (and record) their own songs about bones.
TEACHING STRATEGIES 1. Using a skeleton to demonstrate bones and types of joints is very helpful. In lieu of a skeleton, some excellent poster-sized pictures of the human skeleton are available. 2. When teaching the vertebral bones, a memory trigger is to teach students we have breakfast at 7 (number of cervical vertebrae), lunch at 12 (number of thoracic vertebrae), and dinner at 5 (number of lumbar vertebrae). 3. When teaching the bones of the lower leg, it can be confusing trying to remember which bone is the fibula and which is the tibia. The bigger word (more letters) is the smaller bone—so the fibula is the smaller of the two lower leg bones, whereas the tibia is a shorter word but applies to the bigger bone. 10
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4. When teaching the bones of the forearm, remind students that we check a radial pulse at the juncture of the thumb and wrist—the same side where the radius bone is located. FACTOIDS 1. This is a weird little fact. Did you know that it is perfectly legal to sell human bones? Although certain antique specimens are protected, all other human bones are saleable. Prior to 1985, the main supplier of human material for medical use was India. There are even websites that sell human bone jewelry. Care to buy a bone necklace? 2. The human skeleton has many of the same functions as the skeletons of other animals. Dogs have 319 bones, and cats have 230 bones. 3. The largest bone in the human body is the pelvis, composed of six bones joined together. The longest bone is the femur, making up almost one-quarter of the body’s total height. The smallest bone is the stirrup in the ear, hardly larger than a grain of rice. Cartilage rots faster than bone, so after death, skulls have no nose or ears because they are made of cartilage. 4. There are more than 20 bones in each foot. Foot bones grow faster than any other bones in the body. ETHICAL DILEMMAS 1. A procedure called limb lengthening can be done for those with short stature. The procedure basically requires fracturing the bone at the epiphyseal (growth) plate and inserting a metal plate. A screw, located exterior to the body, is turned daily, separating the metal plates to allow the bone to build continuously, adding height, until the desired inches have been added to the bone. It is possible to add several inches in height with this surgery, but it takes approximately 1 month per inch of height. No weight bearing is allowed until the metal plate and screw are removed and the bone is completely healed. Although this procedure will help short-stature children grow taller, is it ethical to put them through such a painful procedure? 2. Leukemia can be fatal. Many new treatments have improved the odds for survival, not the least of which is bone marrow transplantation. The best match for a bone marrow transplant is a sibling. In some cases, a parent has chosen to have a baby so the stem cells can be removed from the umbilical cord to be used for bone marrow transplantation into a sick child. Is it ethical to have a baby just so the umbilical stem cells can be used to save another child in the family? ANSWERS TO TEST YOUR KNOWLEDGE Test Your Knowledge 6–1 Answers, p. 105 1. Answers to labelling diagram shown top to bottom: Proximal epiphysis (B) Spongy bone (D) Compact bone (E) 11
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Medullary cavity (F) Periosteum (C) Diaphysis (A), this is on left side of figure Epiphyseal plate (G) Distal epiphysis (B) 2. Found in the skull, clavicle, vertebrae of the spinal column, sternum, ribs, pelvis, and the epiphysis of the long bones and is needed for the production of red blood cells. 3. Provides support and allows for movement, protects organs, produces red blood cells, and acts as storage for minerals and fats. 4. b 5. a 6. b Test Your Knowledge 6–2 Answers, p. 109 1. a 2. d 3. b 4. c 5. d 6. a 7. a. comminuted b. greenstick c. compound Test Your Knowledge 6–3 Answers, p. 113 1. d 2. b 3. d 4. b 5. a 6. a 7. c
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Test Your Knowledge 6–4 Answers, p. 121 1. d 2. c 3. c 4. d 5. b 6. b 7. d ANSWERS TO CASE STUDY, P. 139 a. Rosemary deAngelo appears to have osteoporosis. b. There are decreased bone density, holes in the bones, and bone weakness. c. The patient should stop smoking, drink less coffee, take a calcium supplement with vitamin D, and begin an exercise program if possible. There are also several osteoporosis drugs on the market. Perhaps one of them would help. ANSWERS TO REVIEW QUESTIONS, P. 140 1. a 2. b 3. b 4. d 5. b 6. b 7. a Fill in the Blank 1. There are many large appendicular bones: femur, pelvis, humerus, scapula, tibia, fibula, ulna, and radius. 2. Cartilage is found in many places in the body: ears, nose, thoracic cage, joints, between vertebrae, larynx, and trachea. 3. Synovial fluid 4. osteoblasts 5. osteoclasts 13
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6. touching or reduced or immobilized 7. manubrium Short Answer 1. Tendons attach muscle to bone. Ligaments attach bone to bone. 2. During the process of endochondral ossification, a cartilage model is first surrounded by a bone collar. This causes the deterioration of cartilage inside the bone. Periosteal bud invades, bringing blood vessels and cells. Medullary cavity forms, as does a primary ossification center. Bone continues to replace cartilage. A secondary ossification center forms in epiphysis. 3. Joints can be classified functionally as immovable, slightly movable, or freely moving. Joints can be classified structurally as fibrous (united by connective tissue strands), cartilaginous (united by cartilage), or synovial (united by fluid filled joint cavity). 4. The types of movements possible in freely moving joints include the following: flexion— decreasing the angle of joint; extension—increasing angle of a joint; plantar flexion— pointing toes down; dorsiflexion—bending the foot up toward the body; abduction— moving away from the body’s midline; adduction—moving toward the midline of the body; inversion—turning the foot inward toward the other foot; eversion—turning the foot outward away from the opposing foot; supination—turning the hand palm-up; pronation— turning the hand palm-down; circumduction—circular arm movement; rotation—spinning on axis; protraction—drawing part forward; retraction—drawing part backward. 5. Forensic pathologists can use many types of characteristics to tell age, sex, or health. The presence of an epiphyseal plate indicates the skeleton has not reached the end of puberty and is still growing. Male skeletons are “masculinized” with denser bones, more obvious surface features, and a narrower pelvis than female skeletons. Some disorders such as arthritis, osteoporosis, and tuberculosis, as well as nutritional status, cause changes in bone matrix or anatomy. Movement sculptures bone so experts can often tell the type of work done by a person.
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Name __________________ CHAPTER 6—WORKSHEET Multiple Choice 1) These bones are oddly shaped (like jigsaw puzzle pieces): A) Long bones B) Short bones C) Irregular bones D) Flat bones 2) The outer covering of a bone is called: A) endosteum. B) osteon. C) periosteum. D) trabeculae. 3) Which kind of bone cell tears down bone to release calcium and phosphate into the blood? A) Osteoprogenitor cells B) Osteoclasts C) Osteoblasts D) Osteocytes 4) Which type of joint is filled with fluid? A) Cartilaginous joint B) Synovial joint C) Fibrous joint D) Endohydrous joint 5) The thumb is an example of a __________ joint. A) ball-and-socket B) hinge C) pivot D) saddle 15
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Fill in the Blank 6) The _____ is the long, narrow portion of a long bone. 7) The production of red blood cells in red bone marrow is called _____. 8) The thin band of cartilage where bone growth occurs is called the _____. 9) The flexible tissue that acts as a cushion between bones is called _____. Worksheet—p. 1 of 3 Matching Please match each term with the appropriate definition. 10) _____ Flexion
A. Straightening a joint
11) _____ Abduction
B. Turning the hand so the palm faces downward
12) _____ Adduction
C. Pointing the toes down
13) _____ Pronation
D. Moving toward the body’s midline
14) _____ Extension
E. Bending a joint
15) _____ Plantar flexion
F. Turning the sole of the foot inward
16) _____ Supination
G. Turning the hand so the palm faces upward
17) _____ Dorsiflexion
H. Turning the sole of the foot outward
18) _____ Inversion
I. Moving the foot so the toes point up
19) _____ Eversion
J. Moving away from the body’s midline
Please match each statement with the type of bone it best applies to. Letters will be used more than once. 20) _____ Contains trabeculae. 21) _____ Contains cylindrical structures called osteons. 22) _____ Is light, and provides room for red bone marrow. 23) _____ Is dense and very strong. 24) _____ Is typically found on the outer surface of a bone. 25) _____ Is typically found in internal areas of a bone. A. Compact bone B. Spongy bone 16
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Worksheet—p. 2 of 3 Short Answer/Essay 26. At approximately what age do a person’s bones begin breaking down faster than they are built up? (In other words, at what age can a person expect to begin losing bone mass?) __________________________________________________________ __________________________________________________________ __________________________________________________________ 27. List the steps in bone repair. __________________________________________________________ __________________________________________________________ __________________________________________________________ 28. Explain the difference between a ligament and a tendon. __________________________________________________________ __________________________________________________________ __________________________________________________________ Worksheet—p. 3 of 3 ANSWER KEY Chapter 6—Worksheet 1) C 2) C 3) B 4) B 5) D 6) diaphysis 7) hemopoiesis or hematopoiesis 8) growth plate (epiphyseal plate) 9) cartilage 10) E 17
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11) J 12) D 13) B 14) A 15) C 16) G 17) I 18) F 19) H 20) B 21) A 22) B 23) A 24) A 25) B 26) People begin to lose bone mass in their 50s. 27) Hematoma formation/inflammation; soft callus; bony callus; remodeling 28) A ligament connects bones to each other. A tendon connects muscles to bones.
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Name __________________ LABELING ACTIVITY INSTRUCTIONS: Please label the following diagram of a joint.
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LABELING ACTIVITY ANSWER KEY
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Chapter 7 THE MUSCULAR SYSTEM: MOVEMENT FOR THE JOURNEY
LEARNING OUTCOMES Differentiate the three major muscle types. Explain the difference between voluntary and involuntary muscles. Explain the types of skeletal muscle movement and the relationship between muscles. Review movement terminology. Identify and explain the components of a muscle cell. Describe the cellular activities required for muscle movement. Discuss how muscles receive the fuel they need to function. Identify specific skeletal muscles in different body regions. Define function and location of visceral or smooth muscle. Describe the function and actions of cardiac muscle. Name common disorders of the musculoskeletal system.
MULTIMEDIA FOUND ON THE POWERPOINT LECTURE OUTLINE 1. Muscle Contraction Animation (slide 58) 2. Forearm and Hand Muscles Animation (slide 69) 3. Head and Neck Muscles Animation (slide 70) 4. Hip and Thigh Muscles Animation (slide 71) 5. Leg and Foot Muscles Animation (slide 72) 6. Lower Limb Muscles Animation (slide 73) 7. Female Pelvic Muscles Animation (slide 74) 8. Shoulder and Arm Muscles Animation (slide 75) 9. Trunk and Abdominal Muscles Animation (slide 76) 10. Upper Arm Muscles Animation (slide 77) 11. Myofacial Massage Video (slide 98) 1
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12. Neuromuscular Massage Video (slide 99) 13. Western Massage Video (slide 100) 14. Physical Therapy Video (slide 103) 15. Occupational Therapy Video (slide 104) 16. Massage Therapy Video (slide 105) 17. Kinesiology Video (slide 106)
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LECTURE OUTLINE I. Introduction A. The muscular system allows for movement. 1. External motion of the arms and legs 2. Internal motion including the movement of the digestive system, the cardiovascular system, and the respiratory system B. Different types of muscles allow for both external and internal movement. II. Overview of the Muscular System A. Types of Muscles 1. Muscle is a general term for all contractile tissue. 1. Contraction—muscle tissue becomes short and thick because of a nerve impulse. 2. Relaxation when impulse ends 3. Alternating contraction and relaxation causes movement. B. Muscle tissue is constructed of bundles of these fibers, approximately the thickness of human hair. C. Skeletal muscle 1. Voluntary muscle attached to bones; provide movement for the body. 2. Striated—look striped D. Smooth muscle 1. Also called visceral muscle 2. Found in hollow organs (except heart) and tubes, such as blood vessels 3. Involuntary muscles; slower than skeletal muscles E. Cardiac muscle 1. Solely found in the heart wall 2. Completely involuntary F. Muscle characteristics 1. Extensibility 2. Contractility 3
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3. Excitability 4. Elasticity G. Muscle Tone 1. Tonus (muscle tone)—partial contraction of a muscle with resistance to stretching 2. Hypertrophy—increased muscle size 3. Atrophy—muscle wasting from disuse III. Skeletal Muscles A. Skeletal muscles are attached to bones and provide movement for the body. 1. Tendons are fibrous tissues that attach skeletal muscles to bones. 2. Ligaments attach bone to bone. 3. Aponeuroses: connective tissue that attaches a muscle to a bone or soft tissue without a tendon 4. Called voluntary because movement is controlled by conscious thought 5. Responsible for movement and maintaining posture 6. Produce heat. B. Skeletal Muscle Movement 1. Contraction and relaxation a. Contraction—shortening of muscle b. Primary mover (or agonist)—chief muscle causing movement c. Synergist—assists the primary mover. d. Antagonist—opposes agonist. e. Attachments i. Point of origin—attached to the stationary bone ii. Point of insertion—attached to the moving bone f. All movement is a result of contraction of primary movers and relaxation of opposing muscles. g. Action—insertion moves toward origin. 2. Movement Terminology a. Rotation—circular movement that occurs around an axis b. Circumduction-- the movement of a limb in a circle 4
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c. Abduction—movement away from the midline d. Adduction—movement toward the midline e. Extension—increasing the angle between two bones connected at a joint (extensor muscle) f. Flexion—decreasing the angle between two bones (flexor muscle) IV. Muscular Movement at the Cellular Level 1. The Functional Unit of the Muscle a.
Muscle Fibers i. Each muscle is surrounded by connective tissue, continuous with the tendon, called epimysium. ii. Inside the muscles are bundle of fibers (cells) surrounded by perimysium. The bundles are called fascicles.
iii. Several muscle fibers can be bundled together to form a specific muscle segment. iv. Each muscle is encased in a connective tissue (endomysium) and filled with cylinders called myofibrils. vi. For contraction to take place, each fiber must possess many functional contractile units called sarcomeres. b. Sarcomeres i. Sarcomeres are the functional contractile units of each fiber. ii. Each sarcomere has two types of threadlike structures called thick and thin myofilaments. iii. Thick myofilaments are made up of the protein myosin. iv. Thin myofilaments are made up of the protein actin. v. The sarcomere has the actin and myosin filaments arranged in repeating units separated from each other by bands called Z lines. vi. Other modifications for contraction: sarcolemma, sarcoplasmic reticulum (SR), T-tubules
vi. Repeating units of actin and myosin cause striated appearance. 2. The Mechanism of Muscle Contraction i. Acetylcholine, a neurotransmitter, is released from the nervous system. ii. Acetylcholine opens sodium channels on muscle fiber surface. iii. Sodium ions flow into muscle fiber, and it becomes excited. 5
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iv. The sodium causes calcium to be released from the sarcoplasmic reticulum, which causes contraction by causing myosin heads to bind to actin filaments (crossbridge formation). v. Energy is needed for contraction and relaxation. a. ATP (adenosine triphosphate) b. Helps the myosin heads form and break the crossbridges with actin. vi. Acetylcholine is broken down by an enzyme acetylcholinesterase. Calcium is stored away from the actin and myosin in the sarcoplasmic reticulum (SR) during relaxation of the muscle. vii. When a body dies, it cannot pump all the stored calcium back out of the muscles. Excess calcium remains in the muscles throughout the body and causes muscle fibers to shorten and stiffen the whole body (rigor mortis). V. Muscular Fuel A. Muscles, like all tissue, need fuel in the form of food and oxygen to survive and function. 1. The body stores glycogen stored in muscle can be converted to glucose. 2. Fat can be stored for energy. 3. Muscle and blood supply a. Higher demand muscles have a greater blood supply to carry muchneeded oxygen. b. The greater blood supply gives them a darker color. c. Lower demand muscles have a smaller blood supply; they are faster, but have less endurance capabilities and a lighter color. 4.
Muscles and body temperature a. Muscles produce heat. b. Producing heat is important in maintaining body temperature. c. Shivering
VI. Skeletal Muscles of Specific Body Regions A. Muscle location, number of origins, action, size, location of attachments, shape, direction of fibers, combination of all 1. Examples: gluteus maximus, biceps brachii, deltoid B. Facial Skeletal Muscles 6
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1. See Figure 7-8 on page 140. C. Anterior and Posterior Trunk Skeletal Muscles 1. See Figure 7-9 on page 141. D. Skeletal Muscles of the Arm and Shoulder 1. See Figure 7-10 on page 141. E. Skeletal Muscles of the Legs 1. See Figure 7-11 on page 142. VII. Visceral or Smooth Muscle 1. Found in hollow organs (except heart) and tubes, such as blood vessels 2. Involuntary muscles; slower than skeletal muscles 3. Action a. Enlarging the diameter of a blood vessel is called vasodilation. b. Decreasing the diameter of a blood vessel is called vasoconstriction. c. Sphincters—contract and relax to open or close tubes. VIII. Cardiac Muscle 1. In heart wall 2. Involuntary 3. Cardiac muscle fibers are shorter, and receive a richer supply of blood, than any other muscle in the body. 4. Fibers are connected by intercalated discs, causing one fiber to contract and then pull the next one into a contraction, creating a domino effect. This wave of motion squeezes blood out very efficiently. 5. Cardiac muscle does not repair itself. Tissue death (necrosis) or damage to cardiac muscle always leaves a scar. IX. Common Disorders of the Muscular System A. Myalgia: pain or tenderness in a muscle B. Fibromyalgia: Sffects women under 40 but is not fully understood; symptoms include aches, pains, and muscle stiffness with specific tender points; cause is unknown but is linked with chronic fatigue syndrome. C. Ataxia: irregular muscle action with lack of coordination D. Paralysis: partial or total loss of function in voluntary muscles; can be either flaccid or rigid paralysis. Copyright © 2016 Pearson Education, Inc. 7
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E. Spasm or cramp: involuntary sudden and violent contraction of a muscle for a prolonged period of time F. Sprains: tears or breaks in ligaments G. Strains: actual tears in muscles or tendons H. Shin splints or medial tibial stress syndrome: inflammatory condition of the extensor muscles and surrounding tissues of the lower leg; often found in runners I. Hernia: tear in the muscle wall through which an organ of the body protrudes J. Tendonitis: inflammation of tendons K. Muscular dystrophy: inherited muscular diseases in which the muscle fibers degenerate and progressive muscular weakness occurs L. Electromyography: a diagnostic test in which a muscle or group of muscles are stimulated with an electrical impulse, causing contraction, allowing the strength of the contraction to be measured M. Neuromuscular disorders 1. Myasthenia gravis a. Gradually increasing profound muscle weakness b. Drooping eyelid frequently the first symptom 2. Guillain-Barré syndrome a. Disorder of the peripheral nervous system that causes flaccid paralysis and the loss of reflexes b. Ascends from the feet and progresses to the head. c. Paralysis peaks in 10–14 days and then subsides gradually. 3. Tetanus a. Creates rigid paralysis, and any minor stimulus causes muscles to go into a major spasm. b. Caused by toxins produced by bacteria found in the ground and can be spread by any type of puncture, not just a rusty nail.
CLASSROOM ACTIVITIES 1. Have students stand and bend a joint, then discuss what muscles are required for that action as well as the antagonist movement that changes the joint back to the original position. 8
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2. Play round robin, going around the room and asking students to name the muscles as you point to them. Keep going around the room until all muscles are covered. This game can also be used as a group oral quiz, encouraging all students to study hard to avoid bringing down the group average. 3. Assign students to teams and task each group with finding the most creative way to learn the names of muscles, or a muscle group. If time permits, give students the opportunity to try out their strategies and present them to the class. TEACHING STRATEGIES 1. Chicken carcasses can be wonderful teaching tools for the muscular system. Comparing skeletal muscles to organ muscles, such as intestines or the heart, can clearly show the differences between smooth muscles and skeletal muscles. Turkey carcasses frequently even have cardiac muscle to compare. By examining actual muscles, students can more easily understand their structure and function. 2. Relate form to function, explaining why the different muscle types need different anatomies to perform their different functions. 3. Visit YouTube to discover a number of music videos to help students learn and remember muscle names. FACTOIDS 1. Studies show that muscle fatigue has no relationship to the central nervous system or failed neuromuscular transmission. Muscle fatigue is caused by contractile failure of the muscles involved. 2. The body has over 600 muscles, and they come in various sizes and shapes to allow them to perform different functions. Some of the biggest and strongest muscles are in the back, near the spine, helping to maintain upright posture and providing the power to lift and push things. A lifetime of abuse to the back muscles can result in serious and painful problems, sometimes triggered by a task as simple as picking up a pencil: the “straw that broke the camel’s back.” Careful attention to lifting and moving, especially as we approach middle age, when back injury becomes more prevalent, can help prevent debilitating injury. ETHICAL DILEMMAS 1. Discuss the ethical dilemma of the need for transplantable organs and the lack of supply. Should organ donation be mandated? Should everyone who qualifies for a transplant receive one, despite the ability to pay? 2. Should people who destroy their organs through poor lifestyle choices (liver damage from alcohol abuse, heart damage from obesity/smoking) qualify for a transplant? What about income, insurance, and ability to pay—do these factors influence choices? 3. A controversy in the transplant community involves who can donate organs. Currently, 9
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only those who are brain-dead can donate vital organs such as the heart or lungs. However, some feel that many transplantable organs are being lost because those who have had life support withdrawn but are not legally brain-dead cannot donate. Should this be allowed? What about prisoners sentenced to death; should they donate organs instead of being put to death by the state? 4. There are several ways to increase muscle strength, including using drugs like steroids or growth hormone. Is it ethical for athletes to use these substances? Why or why not? If it’s not ethical, why do so many resort to banned substances? ANSWERS TO TEST YOUR KNOWLEDGE Test Your Knowledge 7–1 Answers, p. 128 1. c 2. d 3. b 4. d 5. d
Test Your Knowledge 7–2 Answers, p. 133 1. rotation 2. flexion or adduction 3. extension or abduction 4. agonist or primary mover 5. point of origin 6. kinesiology
Test Your Knowledge 7–3 Answers, p. 137 1. actin 2. calcium and ATP 3. sarcomere 4. acetylcholine (ACh) 5. myosin; actin 6. acetylcholine (ACh)
Test Your Knowledge 7–4 Answers, p. 139 1. hamstrings 10
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2. quadriceps; pelvis; patella and tibia 3. sternocleidomastoid 4. gastrocnemius 5. biceps brachii; triceps brachii 6. hamstrings 7. vastus lateralis
ANSWERS TO THE CASE STUDY, P. 145 a. Guillain-Barré b. Respiratory arrest c. Must monitor respiration rate, blood oxygen and carbon dioxide, and pulse rate. d. Disuse of muscles leads to atrophy. e. This patient will be helpless soon. Everything must be done for the patient. f. It is usually possible to recover from Guillain-Barré, but it may take months of rehabilitation depending on the severity of the disease. ANSWERS TO REVIEW QUESTIONS, P. 146 Multiple Choice 1. a, 2. b, 3. d, 4. b, 5. c, 6. b, 7. b Fill in the Blank 1. spasm/cramp 2. paralysis 3. hernia 4. glycogen 5. Myalgia 6. biceps brachii Short Answer 1. The three major muscle types are skeletal, cardiac, and smooth. The diaphragm (along with dozens of others) is a skeletal muscle. Cardiac muscle is found in the heart wall. Examples of smooth muscle are the walls of the respiratory and digestive systems and the walls of blood vessels. 2. The origin is the stationary muscle attachment. The insertion is attached to the bone that 11
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moves. The action generally moves the insertion toward the origin. 3. Muscles may be names based on size (gluteus maximus), shape (deltoid), fiber direction (external oblique), action (adductor longus), number of attachments (triceps brachii), location of attachments (sternocleidomastoid), location in body (biceps femoris), or a combination (pectoralis major). 4. Skeletal muscle contracts when sodium ion channels open because of stimulation of the muscle because of the release of ATP from the nervous system. This stimulation causes the release of calcium from sarcoplasmic reticulum. This free calcium, in the presence of ATP, allows myosin heads to repeatedly form, break, and reform crossbridges with actin filaments. The repeated connection and disconnection of the myofilaments (actin and myosin) pulls the actin along the myosin, shortening the sarcomere and shortening the muscle itself. 5. From our list, the muscles are the hamstrings (flexor muscles that originate on the pelvis and insert on the tibia) and the quadriceps (extensor muscles that originate on the pelvis and insert on the tibia and patella).
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Name ________________ CHAPTER 7—WORKSHEET Multiple Choice 1) The two threadlike proteins that slide to generate a muscle contraction are: A) actin and myosin. B) myosin and acetylcholine. C) ATP and calcium. D) calcium and actin. E) acetylcholine and ATP. 2) The thick protein filaments in a muscle cell are made of: A) actin. B) myosin. C) ATP. D) calcium. E) acetylcholine. 3) The thin protein filaments in a muscle cell are made of: A) actin. B) myosin. C) ATP. D) calcium. E) acetylcholine. 4) This substance, which is stored in sarcoplasmic reticulum, allows crossbridges to form between actin and myosin: A) Actin B) Myosin C) ATP D) Calcium E) Acetylcholine 13
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5) This substance is an energy molecule. Its function in muscle contraction is to allow myosin heads to attach and reattach to actin, causing sliding of the protein filaments. A) Actin B) Sodium C) ATP D) Calcium E) Acetylcholine 6) This substance helps a muscle stop contracting. A) Actin B) Myosin C) ATP D) Acetylcholinesterase E) Acetylcholine Fill in the Blank 7) The point of _____ is the end of the muscle that is attached to a stationary bone. 8) The point of _____ is the end of the muscle attached to a moving bone. 9) A(n) _____ is a test in which a muscle group is stimulated with an electrical impulse that causes contraction. Matching Please match each muscle with the appropriate action. 10) _____ Vastus lateralis
A. Abducts the shoulder.
11) _____ Triceps brachii
B. Points toes downward.
12) _____ Deltoid
C. Extends the leg.
13) _____ Orbicularis oculi
D. Flexes the knee.
14) _____ Hamstrings
E. Extends the knee.
15) _____ Quadriceps
F. Extends the elbow.
16) _____ Tibialis anterior
G. Closes the eyelid.
17) _____ Gastrocnemius
H. Dorsiflexes the foot.
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Please match each disease with the appropriate description. 18) _____ Strain 19) _____ Ataxia 20) _____ Shin splints 21) _____ Myasthenia gravis 22) _____ Fibromyalgia 23) _____ Muscular dystrophy 24) _____ Tetanus
A. Muscles are irregular and lack coordination. B. A disorder caused by autoimmune attack of the neuromuscular junction C. Pain and inflammation in the anterior lower leg, often associated with running D. An acute muscle injury caused by overstretching E. Progressive muscle weakness and muscle fiber disintegration caused by a genetic defect F. Progressive descending muscle spasms, caused by a particular type of wound infection G. A disorder with chronic, bilateral pain in 11 of 18 specific locations
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Short Answer 25. What muscle is the antagonist to the quadriceps? What action does this antagonist perform? __________________________________________________________ __________________________________________________________ ANSWER KEY Chapter 7—Worksheet 1) A 2) B 3) A 4) D 5) C 6) D 7) origin 8) insertion 9) electromyogram (EMG) 10) C 11) F 12) A 13) G 14) D 15) E 16) H 17) B 18) D 19) A 20) C 21) B 22) G 16
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23) E 24) F 25) The antagonist to the quadriceps is the hamstrings. The hamstrings flex the knee (while the quadriceps extend the knee).
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Name ________________ LABELING ACTIVITY INSTRUCTIONS: Please label the facial muscles in the following diagram.
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LABELING ACTIVITY ANSWER KEY
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Chapter 8 THE INTEGUMENTARY SYSTEM: THE PROTECTIVE COVERING LEARNING OUTCOMES Discuss the functions of the integumentary system. List and describe the layers of the skin. Explain the healing process of skin. Explain the two factors used to assess burns. Describe the ways in which medication is delivered via the integumentary system. Describe the purposes, structure, and growth of nails and hair. Explain how the body regulates temperature through the integumentary system.
Describe Common disorders of the integumentary system.
MULTIMEDIA FOUND ON THE POWERPOINT LECTURE OUTLINE 1. Wound Repair Video (slide 27) 2. Degrees of Burn Animation (slide 50) 3. Chemical Burns Animation (slide 51) 4. Pressure Sores Animation (slide 88) 5. Eczema Video (slide 89) 6. Skin Cancer Video (slide 90) 7. Decubitus Ulcers Video (slide 91) 8. Emergency Medical Technicians Video (slide 92) 9. Nursing Video (slide 93)
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Lecture Outline I. System Overview A. The integumentary system is composed of the skin and its accessory components, including hair, nails, and associated glands. B. Integumentary System Functions 1. Protects from pathogens. 2. Balances fluid levels. 3. Stores fatty tissue for energy supply. 4. Produces vitamin D (with help from the sun). 5. Provides sensory input. 6. Helps to regulate body temperature. C.
The Skin 1. The skin is the largest organ, weighing approximately 20 pounds and covering an area about 20.83 square feet on an adult. 2.
Epidermis a. The outside layer of skin; five sublayers, stratified squamous epithelium b. No blood vessels (avascular) c. Deepest layer: stratum basale, new cells born every 2–4 weeks in the stratum germinativum d. Surface layer: stratum corneum i. Dead cells—flat, scaly, keratinized epithelial cells ii. Sloughed off iii. Replaced by cells from stratum basale e. Melanocytes, make pigment melanin. f. Carotene: pigment that gives skin yellowish hue
3.
g. Color of skin can indicate disease: i. Bilirubin gives the skin a deeper, yellow color. ii. Malfunctioning adrenal gland can cause the skin to turn bronze. iii. Cyanosis, or a blue coloring, results from a drop in oxygenation. Dermis 2
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a. Inferior to epidermis; also called corium b. Connective tissue c. Contains accessory structures: i. Capillaries ii. Involuntary muscles iii. Lymph vessels iv. Hair follicles v. Sudoriferous (sweat) glands a. Two main types i. Apocrine: Secrete at the hair follicles in the groin and anal region as well as the armpits; active around puberty and may act as sexual attractant. ii. Eccrine glands: greater numbers on palms, feet, forehead, and upper lip; temperature regulation b. Body has 3 million sweat glands. c. Sweat has no odor, but bacteria degrade the substances in the sweat over time into chemicals that give off strong smells commonly known as body odor. vi. Sebaceous glands (oil) a. Secrete sebum (oil). b. Sebum keeps skin from drying out and (because of its acid nature) helps destroy some pathogens on skin’s surface. d. Small “fingers” (dermal papillae) of tissue project from the surface of the dermis and anchor this layer to the epidermal layer. e. Collagenous and elastic fibers of this layer help skin flex with the movements and return to normal after being deformed (turgor). 5. Subcutaneous Fascia a. Deepest layer of skin (hypodermis) b. Elastic and fibrous connective tissue and fatty tissue c. Insulation and attachment d. Lipocytes: fat cells to store energy e. Attached to muscle 3
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III. How Skin Heals A. Wound fills with blood (step 1). B. Blood clots, on skin surface, exposed to air—becomes scab (step 2). C. Inflammatory response occurs, with the migration of white blood cells to the damaged area to destroy any pathogens; fibroblasts pull edges of the wound together (step 3). D. If the wound is severe enough, a tough scar composed of collagen fibers may form. E. Burns to the Skin 1. Heat, chemicals, electricity, and radiation can cause burns. 2. Classification by layer or layers of affected skin 1. Depth a. First-degree burns damage only the outer layer, or epidermis. i. Only epidermis ii. Redness, pain, no blister iii. No scarring iv. Partial-thickness burn b. Second-degree burn i. Entire epidermis, portion of dermis ii. Blistering iii. Scarring iv. Often need medical attention. c. Third-degree burn i. All three layers ii. Black, brown, tan, or white iii. Little pain initially iv. Destroys accessory structures. v. Must have medical attention. vi. Full-thickness burn d. Fourth-degree burn i. Most severe 4
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ii. Penetrates to bone. iii. Full-thickness burn 2. Amount of area damaged: the rule of nines a. Head and neck: 9% b. Each upper limb: 9% (× 2 = 18%) c. Front of trunk: 18% d. Back of trunk and buttocks: 18% e. Perineum (including anus and urogenital region): 1% f. Each lower limb 18% (× 2 = 36%) C. Clinical concerns 1. Bacterial infections 2. Fluid loss 3. Heat loss D. Treatment for severe burns 1. Damaged skin must be removed. 2. Skin grafting a. Autografting is using the patient’s own skin. b. Heterografting uses other sources. IV. Nails A. Specialized epithelial cells originating from the nail root B. Keratinized C. The cuticle: fold of tissue that covers the nail root D. Nail body: visible portion; nail matrix is sterile portion beneath nail. E. The pink color of the nail comes from the vascularization of the tissue under the nails, whereas the white half-moon–shaped area, or lunula, is a result of the thicker layer of cells at the base. F. Nails can be used to assess peripheral perfusion. 1. Pink color is clinically significant. 2. If you pinch one of your fingers, the pink color should return within 5 seconds 5
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(usually within 3 seconds), if you have good perfusion, after you release the pressure. 3. If the normal color takes longer to return, it may indicate a problem. 4. Diabetes can cause reduced blood flow to the extremities, a condition called peripheral vascular disease (PVD). 5. Blood clots or vascular spasm can decrease blood flow, as can hypothermia, making peripheral refill slower. 6. Reduced levels of oxygen can cause a blue color to nail beds. V. Hair A. Purpose of hair 1. Body temperature regulation 2. Sensor 3. Protect eyes and nose from foreign objects B. Anatomy of a hair 1. Hair made of keratin 2. Shaft: visible portion of hair; dead cells a. Covered by cuticle b. Cortex is beneath cuticle; made of twisted proteins and melanin pig ments (hair color). 3. Root extends down into the dermis to the follicle. 4. Follicle: Cells grow and divide there. 5. A sebaceous gland is associated with each hair follicle. 6. Sebum production decreases with age. C. Hair color and texture 1. Dependent on the amount of melanin you produce 2. The more melanin, the darker the hair 3. White hair occurs in the absence of melanin. 4. Red hair is the result of hair that has melanin with iron in it. 5. Flat hair shafts produce curly hair, whereas round hair shafts produce straight hair. 6
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6. The life span of hair is dependent on location: Eyelashes last 3–4 months; hair on the head lasts 3–4 years. VI. Temperature Regulation A. Change in size of blood vessels 1. Vasodilation exposes heated blood to external cooling air. 2. Vasoconstriction keeps cooling of blood to a minimum in cold temperatures. B. Sweat glands excrete water onto the skin’s surface, allowing cooling through evaporation. C. Shivering: Muscle contractions produce heat. D. Hairs on your skin stand erect when arrector pili muscles contract, causing goose bumps; these hairs insulate you from cooler surroundings. VII. Common Disorders of the Integumentary System A. Melanoma: deadliest form of skin cancer B. Lesion: any pathological change in skin C. Other disorders (See Table 8-1 on page 163.) CLASSROOM ACTIVITIES 1. There are products that, when applied to the skin, will cause the skin to glow under black lights. Have students apply one of these products to the skin and then perform a thorough handwashing. Once their hands are dry, have them hold their hands under the black light. This is an excellent way of demonstrating good handwashing versus not-so-good handwashing. 2. Have students discuss their experience with sunburns or other first- and second-degree burns. Have them explain what it felt like, how they treated it, and how long the injuries lasted. 3. Have students compare the differences in their hair texture, oil, growth, and so on, allowing students to see the different types of hair common to people of different races and cultures. TEACHING STRATEGIES 1. When discussing one of the functions of the skin—protection or a barrier against pathogen invasion, for example—make the point that the best protection against infection is an intact integumentary system. Discuss how much more easily pathogens can enter the body if there is a break in the skin. Good skin care, when caring for others, is essential to keeping the health care provider safe. This includes good handwashing, application of skin creams 7
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or oils to prevent cracking, and using warm water for handwashing to prevent chapping. 2. Another function of the skin is temperature regulation. Discuss the importance of allowing heat to escape from the body. What treatments are effective in lowering a client’s fever? FACTOIDS 1. The word integument comes from the Latin meaning “to cover.” 2. New shoes may cause the skin of the foot to blister. This is because the epidermis separates from the dermis and tissue fluid may collect in the space. 3.
Contaminated ink used for tattoos has been linked to infection, particularly outbreaks of nontuberculous mycobacterial infection. Those at particular risk of infection, according to the FDA, are people with compromised immune systems, diabetes, or pre-existing heart or circulatory disease.
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Much of the dust in our homes is really an accumulation of dead skin.
ETHICAL DILEMMAS 1. The greatest ethical dilemma that comes from the integumentary system arises from skin color. What possible reason could anyone have for drawing conclusions about a person based on skin color? 2. Some predict that within the next hundred years, we will all have the same skin color as interracial marriages continue. Do you believe this is true? ANSWERS TO TEST YOUR KNOWLEDGE Test Your Knowledge 8–1 Answers, p. 153 1. a. epidermis b. dermis (corium) c. subcutaneous fascia (hypodermis) 2. (any four) a. Protects from invasion of pathogens. b. Keeps you from drying out. c. Storage unit for fatty tissue d. Produces vitamin D. e. Helps regulate body temperature. f. Helps to provide sensory input. 8
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3. d 4. c 5. c 6. b Test Your Knowledge 8–2 Answers, p. 160 1. b 2. c 3. b 4. d 5. c ANSWERS TO THE CASE STUDY, P. 165 She has a contact dermatitis, probably caused by poison ivy. The vesicles have begun to form around her eyes because of contact spreading. When she scratches the vesicles on her legs and then rubs her eyes, she spreads the poison ivy. ANSWERS TO REVIEW QUESTIONS, P. 165–166 Multiple Choice 1. a, 2. b, 3. c, 4. d, 5. B 6. b Fill in the Blank 1. epidermis; dermis; hypodermis 2. eccrine; apocrine 3. sebum 4. freckles 5. bilirubin 6. 3–4 years Short Answer 1. The integumentary system has several functions. It functions as a barrier against bacteria entering the body. The skin, when exposed to sun, produces vitamin D. Because the skin is keratinized, it is waterproof and helps prevent fluid loss. Body fluids can only pass through the skin as sweat. The skin also helps control body temperature. Blood vessels in the skin dilate, sending more blood to the skin if your temperature rises. You also sweat to increase evaporative cooling. Blood vessels in the skin constrict, decreasing blood flow to the skin, if your body temperature falls. Fat storage and sensory input are also skin functions. 9
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2. The epidermis is composed of stratified squamous epithelial cells. In the deepest sublayer, the basal layer (stratum basale), the cells are living. All the cells of the epidermis are born in the basal layer. After the cells are born, they move toward the surface layer, the horny layer (stratum corneum). As they move toward the surface, the cells die and become filled with keratin. Dead cells are sloughed from the surface of the skin and replaced every 2–4 weeks. 3. Melanin is a pigment that shields the nuclei of skin cells from UV radiation. The source of most UV radiation is sunlight. So, as sunlight exposure increases, so does your body’s attempt to protect against UV damage. 4. Burns are classified by depth and extent. Burn depth is divided into four classes. Firstdegree burns are superficial, damaging only the epidermis. Second-degree burns are more serious, damaging the epidermis and part of the dermis. First- and second-degree burns are partial-thickness burns. Third-degree burns burn through the epidermis and the dermis, completely destroying the skin. Fourth-degree burns destroy muscle and bone. Third- and fourth-degree burns are full-thickness burns. The extent of a burn is expressed as the percentage of the body burned. The rule of nines is used to estimate the percentage of the body that is burned. 5. There are several skin accessory structures. Sweat glands secrete water either to regulate body temperature or as a sexual attractant. Hair follicles produce hair and are associated with arrector pili muscles, which create goose bumps when the air is cold. Sebaceous glands, which secrete sebum (oil) to lubricate the skin, are also associated with hair follicles.
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Name ____________ CHAPTER 8—WORKSHEET Multiple Choice 1) The outermost layer of the skin is called the: A) dermis. B) epidermis. C) subcutaneous fascia. D) superficial fascia. 2) The pigment responsible for skin color is: A) melanin. B) keratin. C) collagen. D) elastin. 3) Which skin layer contains hair follicles, sweat glands, sebaceous glands, and nerve endings? A) Dermis B) Epidermis C) Subcutaneous fascia D) Superficial fascia 4) The _____ sweat glands are found in the groin, armpits, and anal region. They become active around puberty. A) eccrine B) apocrine C) endocrine D) alopecia 5) The innermost layer of the skin is called the: A) dermis. B) epidermis. C) subcutaneous fascia. 11
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D) matrix. 6) The fibrous protein that makes up your hair, fingernails, and toenails is called: A) melanin. B) keratin. C) collagen. D) elastin. 7) New hair cells divide and grow in the hair: A) shaft B) root C) follicle D) sebaceous gland 8) These glands produce an oily substance that keeps the skin and hair from overdrying. The oily substance also has antibacterial properties. A) Sudoriferous glands B) Sebaceous glands C) Sweat glands D) Lymph glands 9) Which hair color develops because of the complete absence of melanin production? A) Black B) Red C) White D) Gray 10) Straight hair is a result of hair shafts that are _____. A) square B) round C) flat D) triangular 11) Which of the following statements about the epidermis is not true? 12
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A) The epidermis does not contain any blood vessels. B) The epidermis does not contain any nerve cells. C) The outer layer of the epidermis is composed of dead cells that are constantly sloughing. D) The epidermis is the location where sweat glands and sebaceous glands can be found. 12) Which layer of the epidermis is responsible for producing new cells? A) Stratum corneum B) Stratum germinativum C) Stratum lucidum D) Stratum spinosum Fill in the Blank 13) The cells in the skin that produce pigment are called _____. 14) The sebaceous glands secrete an oil called _____. 15) Cells that pull together the edges of a healing wound are called _____. 16) The white portion half-moon at the base of each nail is called the _____. 17) A nurse pinches her patient’s fingernail and measures how long it takes for the blanched color to return to a normal pink. She has just assessed this patent’s peripheral _____. 18) Red hair is because of altered melanin that contains _____. 19) The _____ muscles attach to hair. When these muscles contract, the hair stands erect. 20) The hypodermis contains _____ cells, called lipocytes. 21) A bleeding wound will eventually form a clot. The top portion of this clot is exposed to air and hardens, forming a(n) _____. Short Answer/Essay 22. Please list three functions of the skin. __________________________________________________________ __________________________________________________________ __________________________________________________________ 23. What kind of problems could develop if skin wounds healed from the outside in (instead of from the inside out)? 13
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__________________________________________________________ __________________________________________________________ __________________________________________________________ 24. Describe two ways the skin can help cool the body when it is too hot. __________________________________________________________ __________________________________________________________ __________________________________________________________ 25. Describe two ways the skin can help retain heat when it is cold outside. __________________________________________________________ __________________________________________________________ __________________________________________________________
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ANSWER KEY Chapter 8—Worksheet 1) B 2) A 3) A 4) B 5) C 6) B 7) C 8) B 9) C 10) B 11) D 12) B 13) melanocytes 14) sebum 15) fibroblasts 16) lunula 17) perfusion (blood flow) 18) iron 19) arrector pili 20) fat 21) scab 22) Answers may include: creating a barrier that prevents pathogens from entering the body; preventing excessive fluid loss; storing fatty tissue for energy supply; producing vitamin D (when exposed to sunlight); providing sensory input; helping to regulate body temperature. 23) If wounds healed from the outside in, bacteria and other pathogens could get trapped in the healing wound and cause an infection. 24) Sweat cools the body by evaporation; Dilation of blood vessels in the dermis brings blood 15
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close to the body surface so the air can cool it. 25) Goose bumps (hairs that are raised by contraction of the arrector pili muscles) create an insulating space between the air and the skin; constricting blood vessels in the dermis divert blood away from the body surface so that the air will not cool it.
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Name _______________ LABELING ACTIVITY INSTRUCTIONS: Please label the following diagram.
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LABELING ACTIVITY ANSWER KEY
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Colbert IRM, 3E Ch 9
Chapter 9 THE NERVOUS SYSTEM (PART I): THE INFORMATION SUPER HIGHWAY
LEARNING OOUTCOMES List and describe the components and basic operation of the nervous system. Contrast the central and peripheral nervous systems. Define the anatomy and function of neuroglia and neurons. Discuss the function of neurons as well as excitable cells, action potentials, graded potentials, and nerve impulse conduction. Explain the difference between chemical and electrical synapses. Discuss the external and internal anatomy and physiology of the spinal cord. Explain how reflexes work. List and describe common disorders of the nerves and spinal cord.
MULTIMEDIA FOUND ON THE POWERPOINT LECTURE OUTLINE 1. Multiple Sclerosis Animation (slide 58) 2. Synapse Animation (slide 64) 3. Muscle Contraction Animation (slide 69) 4. Epidural Placement Video (slide 89) 5. Spinal Cord Anatomy Animation (slide 106) 6. Brachial Plexus Animation (slide 107) 7. Lumbrosacral Plexus Animation (slide 108) 8. Cervical Spine Injuries Video (slide 112) 9. Reflex Arc Animation (slide 116) 10. Carpal Tunnel Syndrome Video (slide 137) 11. Electroneurodiagnosticians Video (slide 138)
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LECTURE OUTLINE I. Organization A. The Parts and Basic Operation of the Nervous System 1. The brain and spinal cord make up the central nervous system (CNS). 2. Everything outside the brain and spinal cord is part of the peripheral nervous system (PNS). 3. The input side of the nervous system is the sensory system. 4. The output side of the nervous system is the motor system. a. The somatic nervous system controls skeletal muscle; voluntary movements. b. The autonomic nervous system controls smooth muscle, cardiac muscle, glands. It is comprised of two branches: i. The parasympathetic system that deals with resting body functioning ii. The sympathetic nervous system, which controls the fight-or-flight response system II. Nervous Tissue A. Neuroglia: specialized cells in the nervous system; perform support functions. 1. The CNS has four types of neuroglia, or glial cells: a. Astrocytes: metabolic and structural support cells b. Microglia: Remove debris. c. Ependymal cells: Cover and line cavities of the nervous system.
d. Oligodendrocytes: Make a lipid insulation called myelin. 2. The PNS has two types of glial cells: a. Schwann cells: Make myelin for the PNS b. Satellite cells: support cells B. Neurons 1. Carry out control functions of nervous system. 2. Each part of a neuron has a specific function. a. Neuron body: cell metabolism b. Dendrites: Receive information from the environment. 2
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c. Axon: Generates and sends signals to other cells. d. Axon terminal: Emits signal from the cell. e. Synapse: Transmits signal to receiving cell. 3. Classification of neurons: structure and function a. Structure i. Sensory neurons: input ii. Motor neurons: output iii. Interneurons (association neurons): communication between neurons b.
Structure i. Bipolar: Has two processes, one axon, and one dendrite. ii. Unipolar: Has one process, split into central and peripheral projection. iii. Multipolar: Has many processes, usually one axon and many dendrites.
III. How Neurons Work A. Excitable cells 1. Can carry a charge. 2. Have membrane potential. a. Each time charged particles flow across a cell membrane, a tiny charge is generated. b. All three types of muscle cells are excitable cells, as are many gland cells. c. Excitable cells are like miniature batteries, able to generate tiny currents simply by changing the permeability of their membranes. B. Action Potentials 1. Action potentials in neurons are known as nerve impulses and allow for signals to travel for cell-to-cell communication. a. Polarized: cell with charge across the membrane when at rest; more negative inside than out b. Depolarized: Charge across membrane becomes more positive. i. Cell is stimulated, sodium channels open. ii. Sodium ions (positively charged) flow into cell; positive feedback loop.
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iii. Cell becomes more positive (depolarized). c. Repolarization: membrane potential returns toward negative; negative feedback loop i. Sodium gates close after less than a millisecond. ii. Potassium gates open. iii. Potassium (also positively charged) leaves the cell, taking its positive charge with it. iv. Cell becomes more negative. d. Hyperpolarization: cell becomes more negative than at rest (after potential). i. All-or-none: an action potential in the cell moving through depolarization, repolarization, and hyperpolarization; does not change size. ii. Refractory period: time during which the cell cannot accept another stimulus C. Graded Potentials 1. Neurons can use their ability to generate electricity to send, receive, and interpret signals. 2. In local potential, the size of the stimulus determines the excitement of the cell. a. Many sensory cells work via local potentials, which is how your CNS determines the size of the environmental change. b. The dendrites carry the depolarization to the sensory neuron cell body, which takes the information and generates an action potential if the stimulus is big enough. 3. One difference between action potentials and local potentials is that action potentials are "all or none," meaning the depolarization always finishes and is always the same size, while local potentials vary in size depending on the stimulus. D. Impulse Conduction i. Movement of an action potential down an axon ii. Speed of impulse conduction is determined by the amount of myelin and the diameter of the axon. a. Myelin i. Lipid insulation formed by oligodendrocytes and Schwann cells
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ii. Myelinated axons look white; unmyelinated are gray. iii. Unmyelinated axon—the action potential can only flow down the axon by depolarizing each and every centimeter of the axon. iv. Myelinated axons—there are nodes of Ranvier, or bare spots, located periodically, and only the nodes must depolarize, impulse skips node to node. b. Diameter of the axon—wider is faster. c. Small, unmyelinated axons have speeds as low as 0.5 meters/second, whereas large-diameter myelinated axons may be as fast as 100 meters/second. E. How Synapses Work 1. Chemical Synapses a. When the action potential arrives at the axon terminal, the terminal depolarizes and calcium gates open. b. Calcium flows into the cell. c. Calcium flow triggers a change in the terminal; tiny sacs in the terminal, called vesicles, release their contents from the cell. d. Vesicles are filled with molecules called neurotransmitters used to send the signal from the neuron across the synapse to the next cell in line. e. Neurotransmitters bind to the cell receiving the signal and open or close gates, while some excite the receiving cell and some calm it down. f. The last step in the transfer of information is to clean up, removing the neurotransmitter from the synapse to prevent it from binding to the receiving cell. i. For example, if the neurotransmitter chemical is acetylcholine (ACh), it will be inactivated by acetylcholinesterase (AChE), 2. Neuromuscular Junction a. Neuromuscular junction is a chemical synapse, a specialized synapse between somatic (voluntary) motor neurons and the skeletal muscles they innervate. b. The surface of the muscle is studded with sodium channels that are ligand-gated. A ligand-gated channel opens or closes when a molecule binds to a receptor that is part of the channel, like a key fitting into a lock. i. Neurotransmitter: acetylcholine, opens sodium channels, causes 5
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skeletal muscle to depolarize so the muscle contracts. ii. Acetylcholinesterase: enzyme responsible for cleaning up the synapse 3. Electrical Synapses a. Some cells need no chemicals to transmit information from one cell to another. b. These synapses are electrical synapses, transferring information freely because they have special connections called gap junctions. c. Such connections can exist between any types of excitable cells. d. They are found in the intercalated discs between cardiac muscle fibers. IV. Spinal Cord and Spinal Nerves A. External Anatomy 1. The spinal cord is a hollow tube running inside the vertebral column, from the foramen magnum to the second lumbar vertebrae. 2. 31 segments, each with a pair of spinal nerves named for the corresponding vertebrae 3. The spinal cord ends at L2 in a pointed structure called the conus medullaris. 1. Hanging from the conus medullaris is the cauda equina (horse’s tail). 2. The spinal nerves L2 through the coccygeal nerves dangle loosely, floating in a bath of cerebral spinal fluid (CSF). 4. The spinal cord has two widened areas, the cervical and lumbar enlargements, which contain the neurons for the limbs. B. Meninges 1. Protective covering of both the brain and spinal cord 2. Three distinct layers: a. Dura mater: tough, fibrous outermost layer b. Arachnoid mater: wispy, filamentous middle layer c. Pia mater: innermost layer, fused to surface of CNS 3. Meningeal spaces a. Epidural space: between spinal cord and vertebrae b. Subdural space: between dura mater and arachnoid mater, small amount of
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fluid c. Subarachnoid space: between arachnoid mater and pia mater; filled with cerebrospinal fluid C. Internal Anatomy of the Spinal Cord 1. The spinal cord is divided in half by an anterior median fissure (deep groove) and a posterior median sulcus (shallow groove). 2. The interior of the spinal cord is then divided into a series of sections of white matter columns and gray matter horns. 3. Horns a. The dorsal horn, involved in sensory functions b. The ventral horn, involved in motor function c. The lateral horn, involved in autonomic functions d. Horns are the regions where the neurons have their cell bodies. 4. Columns also have a ventral, dorsal, and lateral aspect acting as nerve tracts/pathways/axons running up and down the spinal cord to and from the brain. a. Ascending pathways carry information from your sense of touch to the spinal cord and then to your brain from all parts of the skin, joints, and tendons. i. Dorsal column tract carries fine-touch and vibration information to the cerebral cortex. ii. Spinothalamic tract carries temperature, pain, and crude touch information to the cerebral cortex. iii. Spinocerebellar tract carries information about posture and position to the cerebellum. b. Descending pathways carry motor information (orders for voluntary movements) from the brain to the spinal cord. i. The axons from all pathways synapse on motor neurons in the ventral horn. ii. The corticospinal tract carries orders from the brain to the motor neurons in the ventral horn of the spinal cord. iii. The reticulospinal and rubrospinal tracts (along with several other tracts) carry information from the brain to the brain stem and ventral horn, which helps to coordinate movements.
5. The commissures (gray and white) connect left and right halves of the cord. 6. The central canal is a cavity in the center of the spinal cord filled with CSF. 7
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7. The spinal roots project from both sides of spinal cord in pairs, fused to form spinal nerves. a. The dorsal root, with the embedded dorsal root ganglion, a collection of sensory neurons, carries sensory information. b. The ventral root is a motor. 8. Spinal Nerves a. Nerves are the connection between the CNS and the outside environment. b. Nerves are therefore part of the PNS. c. All nerves consist of bundles of axons, blood vessels, and connective tissue. d. Nerves connected to the spinal cord are called spinal nerves, each named for the spinal cord segment to which it is attached. e. All spinal nerves are mixed nerves, carrying both sensory and motor information. f. Cervical, lumbar, and sacral nerves in complex projection are called plexus. 9. Reflexes a. Simplest form of motor output the body can make b. Generally protective, keeping the body from harm c. Involuntary, and usually the response gets bigger as the stimulus gets bigger. d. Familiar reflexes: withdrawal reflex, which allows you to pull your hand away from a hot stove; the vestibular reflex, which keeps you vertical; and the startle reflex, which causes you to jump at loud sounds e. Reflexes can often occur without your brain being involved, involving only your spinal cord. IV. Common Disorders of the Nervous System A. Peripheral neuropathy 1. Encompasses a number of disorders involving damage to peripheral nerves 2. Symptoms vary depending on whether the sensory, motor, or autonomic function is affected. 3. Symptoms include muscle weakness, decreased reflexes, numbness, tingling, paralysis, pain, abnormal sweating, digestive abnormalities, and difficulty controlling BP. 4. Nongenetic neuropathy can be caused by systemic disease, trauma, or infection 8
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and autoimmune disorders. B. Spinal trauma 1. Even though the spinal cord is protected, it can be damaged by trauma. 2. The spinal cord can be partially or completely severed, crushed, or bruised; bruises may resolve with time. 3. Spinal cord injury usually results in paralysis and sensory loss below the injury. 4. Cervical injury may result in quadriplegia and, if the diaphragm is paralyzed, respiratory arrest. 5. Damage in thoracic spinal cord or inferior causes paraplegia; patients can move their arms. C. Guillain-Barré syndrome 1. Guillain-Barré syndrome (GBS) is a paralysis caused by inflammation of peripheral nerves. 2. Develops over variable time periods, causing weakness and ascending paralysis of the limbs, face, and diaphragm. 3. Severe cases require a ventilator to support breathing until paralysis resolves. 4. Cause is unknown, but it frequently occurs after a viral infection; may also be an autoimmune disorder. 5. Disorder is temporary, but many clients require rehabilitation after recovery. D. Myasthenia gravis 1. Autoimmune disorder 2. The immune system attacks and destroys acetylcholine receptors at the neuromuscular junction. 3. Motor neurons can’t communicate with muscles. 4. Eye muscles are usually the first affected; some clients experience difficulty swallowing, chewing, or talking. 5. The disease is progressive, course of disease varies. 6. Treatment includes cholinesterase inhibitors, corticosteroids, immunosuppressant drugs, and plasma exchange; a few clients spontaneously recover. E. Botulism 1. Botulism is a form of paralysis caused by toxins produced by the bacterium Clostridium botulinum. 9
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2. Botulism can be produced by ingesting the toxin in food or can result from wound infection. 3. The bacteria grow most commonly in improperly prepared canned food, especially home-canned food. 4. The toxin keeps neurotransmitters from being released at the neuromuscular junction, causing paralysis. 5. Initial symptoms include visual disturbances, slurred speech, dry mouth, and muscle weakness; paralysis will spread to limbs and respiratory muscles. 6. Botulism is treated with antitoxin and supportive care. F. Meningitis 1. Meningitis is an infection, from either viruses or bacteria, of the meninges. 2. Bacterial meningitis is a potentially fatal infection. a. The bacteria first infect the upper respiratory tract and then travel to the meninges. b. At-risk individuals include the elderly, immunosuppressed patients, very young children, and college students who live in dorms. c. Survivors of meningitis often have severe neurological impairment, including deafness and severe brain damage. 3. Viral meningitis is a much milder version of the disease caused by viruses that enter the mouth. G. Carpal tunnel syndrome 1. Inflammation and swelling of the tendon sheathes surrounding the flexor tendon of the palm 2. It is caused by repetitive motion such as typing on a keyboard. 3. Because of the inflammation, the median nerve is compressed, producing tingling sensations or numbness of the palm and first three fingers. CLASSROOM ACTIVITIES 1. Demonstrate reflex action by tapping with a reflex hammer on the various trigger points, such as just below the patella. Have students watch the result when the proper area is stimulated, then have them practice the maneuver. Discuss reflexes and why they are important. Discuss the effect of a patient in a vegetative state who demonstrates these reflexes, making family believe the patient is more aware of the surroundings than is actually the case. 2. Demonstrate how nerves accommodate a continuous sensation versus how they can poten10
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tiate sensation. For instance, make a hot water bottle or a heating pad as warm as possible without causing a burn. Have students rest it on a forearm for about 20 minutes. Point out how the temperature seems to drop as the neurons become accustomed to the temperature. Discuss the effects this can have on heat/ice therapy and how it might make the client vulnerable to injury. Then have students gently stroke back and forth using just the tip of one finger over exactly the same area of the forearm where the heat source had been. After about 10 minutes, this gentlest of touches begins to burn and become painful. Discuss why this occurs. TEACHING STRATEGIES 1. The nervous system is very complex. Helping students understand the differences between the sympathetic and parasympathetic nervous system requires examples of real-life situations that they can understand. 2. If students are to administer medications, a thorough understanding of how different medications affect different parts of the nervous system is essential. Talk about how anesthetics, analgesics, antidepressants, sedatives, and other types of drugs affect the nervous system. FACTOIDS 1. The human brain has about 100 billion neurons. 2. Neurons range in size from 4 microns to 100 microns wide. If you were to watch a surgery that opened the spinal cord, you would see dozens of white, almost worm-looking, nerves traverse down the cord, one on top of the other, forming a cord that could be compared to a phone trunk. ETHICAL DILEMMAS 1. Research indicates that stem cells may resolve spinal trauma by regrowing attachments between severed nerves. However, many people believe that stem cell research is morally wrong. Is stem cell research morally, ethically permissible if it can resolve spinal trauma, Parkinson’s, and other disease processes? 2. Many people watched the care and rehabilitation Christopher Reeves received. However, most quadriplegics and paraplegics can’t afford that level of care and are often placed in nursing homes, where they receive minimal care. Doesn’t everyone deserve the same level of care? Is it feasible to expect the public health care system to support this level of care?
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ANSWERS TO TEST YOUR KNOWLEDGE Test Your Knowledge 9–1 Answers, p. 172 1. b 2. b 3. c 4. b 5. b Test Your Knowledge 9–2 Answers, p. 176 1. c 2. b 3. b 4. a 5. b Test Your Knowledge 9–3 Answers, p. 179 1. c 2. d 3. c 4. c 5. b Test Your Knowledge 9–4 Answers, p. 186 1. b 2. b 3. b 4. c 5. a ANSWERS TO THE CASE STUDY, P. 188 Dylan’s injury is most likely to the cervical spinal cord. A spinal cord injury is mostly likely because he is paralyzed on both sides of his body. A brain injury would leave him paralyzed on on-
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ly one side, typically. That he cannot breathe points to a high cervical injury. Impulses are not moving from his brain to his cervical plexus, where the phrenic nerve connects. Thus he cannot breathe on his own. ANSWERS TO REVIEW QUESTIONS, P. 188–189 Multiple Choice 1. b, 2. a, 3. d, 4. b, 5. c, 6. b, 7. b, 8. c Fill in the Blank 1. diameter; myelin 2. Action 3. columns; horns 4. CSF; subarachnoid 5. reflex 6. ventral/anterior Short Answer 1. As a neuron is stimulated, sodium channels open and sodium rushes in, bringing positive charges into the cell. The cell becomes more positive, or depolarized. With a brief delay, sodium channels shut, preventing more sodium from entering the cell. Then potassium channels open, allowing potassium to leave the cell. Because potassium is also positively charged, it takes positive charges with it, making the neuron more negative. The neuron is repolarizing. If potassium continues to rush out of the cell, the cell will become more negative than at rest. The cell is then hyperpolarized. 2. The steps in chemical synaptic transmission include the following: An action potential reaches the axon terminal and depolarizes it. Voltage-gated calcium channels open, and calcium rushes into the cell. The calcium coming into the cell triggers exocytosis of vesicles containing neurotransmitter. The neurotransmitters leave the cell, diffuse across the synaptic cleft, and bind to the receptors on the receiving cell. The receiving cell undergoes some kind of permeability change. Then cleanup occurs. 3. The bones of the skull and vertebrae protect the CNS. In addition, three layers of meninges protect the CNS. The outer layer is the dura mater. The middle layer is the arachnoid mater, and the inner layer is the pia mater. CSF is contained in the subarachnoid space and in the hollow spaces inside the CNS. 4. There are four CNS neuroglia. Astrocytes are metabolic and structural support cells. Oligodendrocytes make myelin. Ependymal cells line cavities. Microglia destroy debris. In the PNS, there are two types of neuroglia: Satellite cells are general support cells, and Schwann cells are myelinated axons.
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5. A spinal cord injury at C2 would cause quadriplegia and sensory loss from the neck down. Patients with this injury would likely be ventilator-dependent because of paralysis of the diaphragm. A spinal cord injury at T3 would cause paralysis of some thoracic and abdominal muscles and paraplegia as well as loss of sensation from the chest down. Patients would be able to breathe on their own but might have some difficulty with coughing or shortness of breath because of paralysis of thoracic and abdominal muscles. A spinal cord injury at L2 would cause paraplegia and sensory loss below the waist.
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Name _______________ Chapter 9—Worksheet Fill in the Blank 1) _____ are specialized cells that do all the support activities for the nervous system. 2) _____ are cells that carry out all the control functions for the nervous system. 3) The _____ are the protective membranes that surround the brain and spinal cord. 4) The fluid surrounding the brain and spinal cord is called _____. Matching Please match each branch of the nervous system with the appropriate definition. 5) _____ Central nervous system
A. Composed of the nerves
6) _____ Peripheral nervous system
B. Controls voluntary muscle movements.
7) _____ Sensory system
C. Carries instructions from the brain down to the body tissues.
8) _____ Motor system 9) _____ Autonomic nervous system
D. Controls smooth and cardiac muscle (internal organs).
10) _____ Somatic nervous system
E. Involved in resting and digesting
11) _____ Sympathetic nervous system
F. Composed of the brain and spinal cord
12) _____ Parasympathetic nervous system
G. Involved in “fight-or-flight” response H. Carries information about the environment up to the brain.
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Please match each term with the appropriate definition. 13) _____ Synapse
A. The portion of the neuron that receives information from the environment
14) _____ Dendrite
B. The portion of the neuron that conducts action potentials
15) _____ Neurotransmitter 16) _____ Axon
C. The tiny space between the neuron sending the signal and the cell receiving the signal
17) _____ Myelin 18) _____ Action potential
D. Special chemicals used to send a signal across the synapse E. A wave of depolarization and repolarization that travels down an axon F. A lipid sheath that surrounds and insulates the axon
Multiple Choice 19) Which is the outermost layer of the meninges? A) Pia mater B) Dura mater C) Arachnoid mater 20) Which is the innermost layer of the meninges? A) Pia mater B) Dura mater C) Arachnoid mater 21) A cell that is not stimulated or excited is: A) depolarized. B) hyperpolarized. C) polarized. Short Answer/Essay 22. A patient has just received an injection into the epidural space. Where is the epidural space located? (In other words, where was the medication injected?) __________________________________________________________
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__________________________________________________________ __________________________________________________________ 23. A patient has been diagnosed with a subarachnoid hemorrhage. Describe exactly where blood is collecting in this patient’s head. __________________________________________________________ __________________________________________________________ __________________________________________________________ 24. Which disease is characterized by an autoimmune attack on myelin in the CNS? __________________________________________________________ __________________________________________________________ __________________________________________________________ 25. What viral disease can cause destruction of motor neurons in the spinal cord? __________________________________________________________ __________________________________________________________ __________________________________________________________ ANSWER KEY Chapter 9—Worksheet 1) Neuroglia (glial cells) 2) Neurons 3) meninges 4) CSF (cerebrospinal fluid) 5) F 6) A 7) H 8) C 9) D 10) B 11) G
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12) E 13) C 14) A 15) D 16) B 17) F 18) E 19) B 20) A 21) C 22) Outside the dura mater; between the dura mater and the vertebra 23) Below the arachnoid mater; between the arachnoid mater and pia mater 24) Multiple sclerosis 25) Polio
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Name _______________ LABELING ACTIVITY INSTRUCTIONS: Please label the following diagram.
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LABELING ACTIVITY ANSWER KEY
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Chapter 10 THE NERVOUS SYSTEM (PART II): THE TRAFFIC CONTROL CENTER LEARNING OUTCOMES Locate and define the internal and external structures of the brain and their corresponding functions. List and describe the cranial nerves and their functions, and discuss how they differ from spinal nerves. Discuss the integration of the brain, spinal cord, and peripheral nervous system. Describe the somatic sensory system. Describe the motor system functions of the brain with related structures. Contrast the parasympathetic and sympathetic branches of the autonomic nervous system. Discuss the limbic system and reticular formation. Discuss some representative diseases of the nervous system. MULTIMEDIA FOUND ON THE POWERPOINT LECTURE OUTLINE 1. PET Scan Animation (slide 30) 2. Parkinson's Disease Video (slide 89) 3. Absence Seizures Video (slide 120) 4. Complex Partial Seizures Video (slide 121) 5. Generalized Tonic–Clonic Seizure Video (slide 122) 6. Epilepsy Video (slide 123) 7. Stroke Animation (slide 129) 8. Shock Animation (slide 132) 9. Alzheimer's Disease Video (slide 136) 10. Autism Video (slide 137) 11. Bipolar Disorder Video (slide 138) 12. Dissociative Identity Disorder Video (slide 139) 13. Obsessive Compulsive Disorder Video (slide 140) 14. Schizophrenia Video (slide 141) 15. Panic Attacks Video (slide 142) 16. Delirium Animation (slide 143) 17. Pharmacy Video (slide 144) 1
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LECTURE OUTLINE I. The Brain and Cranial Nerves A. The brain and cranial nerves represent the major control systems of the nervous system. B. The brain acts more as the main processor and director of the entire system. C. The cranial nerves leave the brain and go to specific body areas, where they receive information and send it back to the brain (sensory), and the brain sends instructions to move (motor). D. At the top of the spinal cord, beginning at the level of the foramen magnum and filling the skull, is the brain. E. The Brain's External Anatomy 1. Cerebrum a. Largest part of the brain b. Divided into the right and left hemisphere by the longitudinal fissure c. Divided from the cerebellum by the transverse fissure d. Convoluted surface of the cerebrum is not smooth. i. Ridges (gyri) and grooves (sulci) ii. Increase surface area of the brain. iii. Most sulci are extremely variable in their locations among humans. e. Lobes i. Lobes are named for the skull bones that cover them and occur in pairs, one in each hemisphere. ii. Frontal: anterior, separated from the rest of the brain by the central sulci, responsible for motor activities, conscious thought, and speech iii. Parietal: posterior to frontal lobes, involved with body sense perception, and speech iv. Occipital: posterior to parietal lobes, responsible for vision v. Temporal: inferior lobes, separated by the lateral sulci, involved in hearing and integration of emotions vi. Insula: deep inside the temporal lobes, autonomic functions f. On either side of the central sulcus are two gyri: the precentral gyrus, anterior 2
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to the central sulcus, and the postcentral gyrus, posterior to the central sulcus. g. Speech areas i. Broca’s: frontal area, motor for speech ii. Wernicke’s: parietal, understanding language h. Information is contralateral, meaning the right side of the body is controlled by the left side of cerebrum, and vice versa. 2. Cerebellum a. Posterior to the cerebrum b. Divided into hemispheres by a raised ridge called the vermis c. Surface is convoluted, similar to the cerebrum. d. Cerebellum is involved in sensory and motor coordination and balance. 3. Brain stem a. A stalk-like structure inferior to and partially covered by the cerebrum b. Three sections: i. Medulla oblongata: continuous with the spinal cord, responsible for impulses that control heartbeat, respiration, and blood vessel diameter ii. Pons: superior to the medulla oblongata; plays role in respiration. iii. Midbrain: most superior portion of the brain stem, completely covered by cerebrum; a pathway to relay visual and auditory impulses and other information to the cerebrum C. The Brain's Internal Anatomy 1. White matter of the brain is surrounded by gray matter. 2. Cortex: layer of grey matter surrounding the white matter a. Cerebral cortex b. Cerebellar cortex 3. Nuclei: deep islands of gray matter surrounded by white matter 4. Ventricles a. Fluid-filled cavities in the brain b. Continuous with the central canal of the spinal cord and the subarachnoid space of both the brain and the spinal cord 3
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i. Lateral ventricles (ventricles 1 and 2) in cerebrum ii. Third ventricle is in the diencephalon (a region between the cerebrum and brain stem). iii. Fourth ventricle in the inferior part of the brain between the medulla oblongata and the cerebellum 5. Cerebrum a. Lobes (frontal, parietal, temporal, and occipital) are clearly visible. b. On either side of the central sulcus are two gyri, the precentral gyrus anterior to the central sulcus and the postcentral gyrus posterior to the central sulcus. c. Right and left hemispheres are connected by several white matter pathways surrounding the lateral ventricles called the corpus callosum, the fornix, and the anterior commissure. 6. Diencephalon a. Inferior to cerebrum, not visible from the exterior b. Thalamus, hypothalamus, pineal body, and pituitary gland c. Third ventricle and a number of nuclei that are part of the basal nuclei and limbic system d. Specific nuclei of the diencephalon are responsible for controlling hormone levels, hunger and thirst, body temperature, sleep–wake cycles, and flow of information around the brain. 7. CSF circulation and hydrocephalus a. The ventricles of the brain, the central canal of the spinal cord, and the subarachnoid space surrounding both the brain and spinal cord are filled with CSF. b. Filtered from blood in the ventricles by tissue called choroid plexus. c. Made in lateral ventricles, flows through a tiny opening into the third ventricle and then through another opening into the fourth ventricle, then into the central canal of the spinal cord and the subarachnoid space. Returns to the blood via special “ports” between subarachnoid space and blood spaces in the dura mater. d. Balance of CSF made and CSF reabsorbed by the blood is very important. e. Too much CSF causes pressure inside the skull to rise and eventually crushes brain tissue. f. Hydrocephalus: water on the brain, too much CSF 4
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8.
Cerebellum a. Cerebellum has a grey matter cortex and a white matter center, known as the arbor vitae (tree of life). b. Cerebellum also has nuclei that coordinate motor and sensory activity. c. Cerebellum essentially fine-tunes voluntary skeletal muscle activity and helps in the maintenance of balance.
III. Cranial Nerves A. Like the spinal cord that has spinal nerves, the brain has nerves called cranial nerves. B. Input and output pathways for the brain C. There are only 12 pairs of cranial nerves, all but two of which arise from the brain stem. D. Some are mainly sensory, others are mainly motor, and some are mixed nerves. E. Cranial nerves are much more specialized than spinal nerves. F. Cranial nerves carry sensory and motor information for the head, face, and neck as well as visual, auditory, smell, and taste sensations. IV. The Big Picture: Integration of Brain, Spinal Cord, and PNS A. The Somatic Sensory System 1. Includes fine touch (somatic sensation), crude touch, vibration, pain, temperature, and body position. 2. Comes into both the brain and the spinal cord. 3. To attach meaning to the sensation, it must get to the brain for interpretation. a. Somatic sensory association area: Information comes into the spinal cord via the dorsal root. b. Three pathways or tracts in the white matter of the spinal cord carry information to brain. i. Dorsal column tract carries fine touch and vibration information to the cerebral cortex. ii. Spinothalamic tract carries temperature, pain, and crude touch to the cerebral cortex. iii. Spinocerebellar tract carries information about posture and position to the cerebellum. 4. Information eventually reaches primary somatic sensory cortex: 5
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a. Postcentral gyrus of the parietal lobe b. Has maps that correspond to body parts; contralateral. c. Neurons in the SS cortex allow conscious sensation. d. Size of map determined by sensitivity of body part B. Somatic Sensory Association Area 1. In parietal lobe; just posterior to somatic sensory cortex 2. Allows for interpretation of somatic sensory information. 3. SS cortex notes location and type of sensation; SS association area interprets information. C. The Motor System 1. The motor system is also a hierarchy, working in parallel with the SS system, with two obvious differences: a. Information moves in the opposite direction from brain to spinal cord. b. The motor system has two divisions: the somatic motor system and the autonomic nervous system. 2. Premotor and prefrontal areas, frontal lobes, plan movements. 3. The plan from these two areas is sent to the primary motor cortex. 4. The primary motor cortex a. Precentral gyrus in the frontal lobe, just anterior to the SS cortex b. Map of the body; contralateral c. The size of the map is proportional to the amount of movement control. D. Subcortical Structures 1. The plan for movement leaves the motor cortex and connects with neurons in the thalamus, located in the diencephalon. 2. The thalamus, basal nuclei, and cerebellum are part of a complicated motor coordination loop. 3. Here, movement must be fine-tuned, posture and limb position are judged, other movements are turned off, and movement and sensation are integrated. 4. Part of the limbic system, which controls emotion and mood E. Spinal Cord Pathways 6
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1. Direct pathways: corticospinal and corticobulbar a. Information carried from motor cortex to ventral horn motor neurons or motor nuclei of brain stem b. Motor neurons project to skeletal muscles via the cranial nerves or the ventral roots, and spinal nerves send orders to the skeletal muscles to carry out the planned movement. c. Fine-tuning of reflexes 2. Indirect pathways a. Project from subcortical structures, including cerebellum, thalamus, and basal nuclei b. Coordination of movements F. Role of the Cerebellum 1. Both motor and sensory inputs and outputs from the cerebral cortex, thalamus, basal nuclei, and spinal cord 2. Compares planned movement with actual and fixes any mismatch. 3. Functions are subtle. VI. Autonomic Nervous System A. Involuntary motor system: Controls organs and glands. B. Anatomy 1. Neurons in lateral horn of spinal cord 2. Autonomic neurons do not project directly to muscles, but make a synapse in a ganglion outside the CNS. 3. Ganglion: group of nerve cell bodies outside of the CNS 4. A second motor neuron, called a postganglionic neuron, projects to the muscle. 5. No autonomic neurons in the cervical spinal cord C. Sympathetic Branch 1. Fight-or-flight response, charged with responding to emergencies 2. Increase heart rate, BP, and sweating, also causes dry mouth—symptoms of an adrenaline rush. c. Preganglionic neurons in the thoracic and first two lumbar segments of the spinal cord 7
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d. Ganglia form a pair of chainlike structures that run parallel to the spinal cord (paravertebral ganglia). e. Postganglionic cells release the neurotransmitter norepinephrine. D. Parasympathetic Branch 1. “Resting and digesting” because it has the opposite effect of the sympathetic division 2. Responsible for everyday activities as well as reversing the sympathetic effects 3. Decreased heart rate, respirations, and blood pressure and increased digestive activity, including salivation and stomach activity 4. Preganglionic neurons of the parasympathetic system are in brain stem and sacral spinal cord. 5. Ganglia are near target organs. 6. Postganglionic neurons release acetylcholine. E. Putting the Autonomic System All Together 1. Stimulated sympathetic nervous system: Impulses are sent from the thoracolumbar region of the spinal cord to preganglionic fibers, which release the neurotransmitter acetylcholine. 2. Acetylcholine combines with receptors on the postganglionic neurons, which generate an action potential and carry the impulse to the target area, where norepinephrine is released. 3. When this occurs at the heart (cardiac muscle), the rate and force of contraction will supply more blood for the fight-or-flight response. 4. When the emergency is over, the sympathetic pathway will not be as active, and the norepinephrine will be metabolized so you don’t remain in that stimulated state. 5. The parasympathetic system now takes over to slow your system down to normal. VII. Other Systems A. Limbic System 1. Series of nuclei in the cerebrum, diencephalon, and superior brain stem 2.
Mood, emotion, and memory
3. One nucleus helps attach emotion to movement; another coordinates emotion and the sense of smell; still another is responsible for storing and retrieving information. B. The Reticular Formation 8
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1. The reticular system is a diffuse network of nuclei in the brain stem that is responsible for “waking up” the cerebral cortex. 2. Reticular system activity is vital for the maintenance of conscious awareness of surroundings. 3. General anesthesia inhibits the reticular system, rendering surgery patients unconscious. 4. Injury because of ischemia, trauma, or drugs can damage the reticular system and lead to coma. IX. Common Disorders of the Nervous System A. Paralysis 1. Paralysis: inability to control voluntary movements 2. Paralysis can be spastic or flaccid. a. Spastic: i. Muscle rigidity, increased muscle tone (hypertonia), and overactive reflexes (hyperreflexia) ii. Caused by interruption of communication between brain and ventral horn neurons iii. Strokes, head injuries, and spinal cord injury can cause spastic paralysis. b. Flaccid paralysis i. Floppy muscles (hypotonia) and decreased reflexes (hyporeflexia) ii. Caused by damage to the nerves; impulses cannot get to the muscles from the motor neuron. iii. Flaccid paralysis occurs with peripheral injury or disorders like polio or Guillain-Barré syndrome. B. Cerebral palsy (CP) 1. Movement disorders that are not progressive and that occur in young children 2. Spastic paralysis 3. Improper development or damage to the motor system of the brain 4. Symptoms range from minor motor loss to significant motor deficits, including the inability to walk or speak. 5. Intelligence may or may not be affected, depending on the cause of CP. 9
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C. Cerebral vascular accident (CVA) 1. CVA, or stroke, is caused by interruption of blood flow to a portion of the brain because of hemorrhage or a blood clot. 2. If oxygen supply is disrupted long enough, brain cells will die. 3. Symptoms vary, depending on area affected, and can include paralysis, inability to speak, blindness, loss of memory, and lack of sensation. 4. Symptoms appear suddenly or can be a series of small, minor strokes; these ministrokes are called transient ischemic accidents (TIAs). D. Traumatic brain injury (TBI) 1. Occurs when force is applied to the skull and causes brain damage. 2. A mild brain injury is called a concussion. E. Huntington’s disease 1. Huntington’s disease is a progressive, genetic disorder causing deterioration of neurons in the basal nuclei and eventually the cerebral cortex. 2. The disease begins with wide mood swings, memory disturbances, writhing movements of the hands or face, or clumsiness; eventually, difficulty swallowing, speaking, and walking as well as memory loss, psychosis, and loss of cognitive function will occur. 3. There is no cure, and most clients die from injuries, infections, or other complications. 4. Genetic testing can identify those at risk. CLASSROOM ACTIVITIES 1. For a fun discussion, talk about science fiction writers’ concepts of brain transplants. If someone else’s brain were transplanted into your skull, would you still be you, or would you be the person who contributed the brain in a new body? Defend your position. 2. Make flash cards with body actions on one side and the location of the brain that controls that action on the other side. Show one flash card to the group and have them tell you the location of the control of that action. You can also ask students to explain where the location of control is as they function in the classroom—writing notes, speaking, drawing pictures, shifting in their seats, and so on. 3. Make a chart with a column for each part of the brain and then place appropriate actions in the proper column. Map things like planning dinner, taking a jog, talking with friends on the phone, studying anatomy, feeling pain, listening to music, and watching TV. TEACHING STRATEGIES 10
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1. Discuss with students the differences in male and female brains. Explain that research has shown that men tend to be more mathematical and logical, whereas women tend to be more verbal and better at language skills. Does this mean girls can’t do math? Does it mean boys shouldn’t be encouraged to discuss feelings? Have students support their beliefs. 2. Have students explain the purpose of the fight-or-flight response, explaining why pupils dilate and decreased gastric acid production occurs. Why is this response important? Relate the fight-or-flight response to stress, both chronic and acute. FACTOIDS 1. The cerebellum was once thought only to assist with motor functions, acting to help other motor regions function. However, during the last decade, further research indicates that the cerebellum is like a powerful computer capable of contributing to motor and mental dexterity, both required for the emergence of fluent human language. It reaches full structural growth by age 15–20. 2. The average human brain weighs about 1400 grams (3 lbs.). Removed from the skull, it looks like a large, pinkish-grey walnut. If the bumps and grooves of the brain were spread out on the floor, they would measure approximately 324 square inches—about the size of a page of a newspaper. Just like fingerprints, the gyri and sulci on the cerebral cortex are different in every brain. 3.
Put together, all of the neurons in the brain make enough electricity to generate a lowwattage light bulb.
ETHICAL DILEMMAS 1. We talk a lot about confidentiality in health care. Regulations such as HIPAA legislate confidentiality for medical records. Yet if a child is admitted to the hospital with a subdural hematoma and child abuse is suspected, we are mandated to report it. Isn’t this a breach of confidentiality? Why is this breach okay? Discuss other situations in which it is okay to breach confidentiality. 2. If you had a child in the first grade and you found out that a child with severe cerebral palsy was going to join the class, how would you feel? Does the presence of CP indicate or predict level of intelligence? 3. Suppose you or someone you loved had a brain tumor. The tumor could be removed, but it would mean losing all your memories. Would you remove it? How would you advise a loved one? What if you lost the ability to speak? To understand spoken language? Written language? ANSWERS TO TEST YOUR KNOWLEDGE Test Your Knowledge 10–1 Answers, p. 194 1. d 11
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2. c 3. d 4. c 5. c 6. b Test Your Knowledge 10–2 Answers, p. 199 1. c 2. c 3. b 4. c 5.
1. hypoglossal; e. control tongue muscles 2. trigeminal; d. chewing 3. vestibulocochlear; b. balance 4. olfactory; c. smell 5. optic; a. vision Test Your Knowledge 10–3 Answers, p. 203 1. a 2. a 3. b 4. c 5. b Test Your Knowledge 10–4 Answers, p. 206 1. a 2. b 3. b 4. b 5. d ANSWERS TO THE CASE STUDY, P. 211 His left frontal lobe is damaged. You can tell because he has lost motor control on the right side but has retained sensation on the right. The motor system is in the frontal lobe, whereas somatic 12
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sensory is in the parietal lobe. Also, the cerebral cortex is contralateral, so loss of movement on the right side of the body would indicate damage to the left side of the brain. He should be able to understand language because his parietal lobe (Wernicke’s area) is undamaged, but actually speaking may be difficult because of damage to Broca’s area in the frontal lobe. ANSWERS TO REVIEW QUESTIONS, P. 211–212 Multiple Choice 1. c, 2. d, 3. a, 4. c, 5. b, 6. b, 7. b, 8. d Fill in the Blank 1. basal nuclei 2. vision 3. descending; ascending 4. limbic system 5. medulla oblongata 6. basal nuclei/thalamus Short Answer 1. There are 12 pairs of cranial nerves, but 31 pairs of spinal nerves. Cranial nerves are attached to the brain, whereas spinal nerves are attached to the spinal cord. Cranial nerves may be sensory, motor, or mixed, whereas spinal nerves are all mixed. Cranial nerves often have specialized functions, but spinal nerves all carry the same kind of information. 2. The sympathetic nervous system controls fight-or-flight response, readying the body to expend energy. The parasympathetic is resting and digesting. The sympathetic neurons are thoracolumbar, whereas the parasympathetic neurons are craniosacral. The sympathetic ganglia are paravertebral, parallel to the spinal cord, whereas the parasympathetic ganglia are near the target organs. The sympathetic postganglionic neurons release norepinephrine, and the parasympathetic postganglionic neurons release acetylcholine. 3. The cerebral cortex generates the movement plan and sends orders directly to the ventral horn motor neurons. In addition, the cortex sends the planned movements to subcortical structures such as the thalamus, basal nuclei, and cerebellum. The subcortical structures fine-tune and coordinate the movement plan, send information down the spinal cord, and correct the orders originally sent by the cerebral cortex if necessary. 4. Somatic sensory information is sensed by receptors in your skin and joints. That information is transferred along a spinal nerve to the dorsal root and to the neuron cell body in the dorsal root ganglion. The information is carried into the spinal cord and enters one of the ascending spinal cord tracts. These tracts take the information to various parts of the brain. Conscious sensation is eventually mapped in the somatic sensory cortex, in the postcentral gyrus, and compared with other information by the somatic sensory association ar13
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ea, allowing understanding. (If the sensory information is on your face or head, the spinal cord is not involved. Information goes into the brain stem via cranial nerves, into a nucleus, and then to the brain.) 5. Movement plans are made in the premotor area and sent to the primary motor cortex in the precentral gyrus. Orders are sent directly from the primary motor cortex to the ventral horn motor neurons. The motor neurons send the orders to skeletal muscles, and they contract. The orders are sent via the ventral roots and spinal nerves. In addition, orders are sent from primary motor cortex to subcortical structures, including the basal nuclei, thalamus, and cerebellum. These nuclei form a complex neural loop that coordinates movements, sending corrective signals down the spinal cord to the ventral horn motor neurons. (If the movements are facial or head movements, the spinal cord is not involved. The motor neurons are in brainstem nuclei and communicate with muscles via cranial nerves.)
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Name ______________ CHAPTER 10—WORKSHEET Matching Please match each portion of the brain with the appropriate description. 1) _____ Cerebrum
A. Collection of white matter that connects the left and right hemispheres
2) _____ Cerebellum
B. Fluid-filled cavities in the brain
3) _____ Brain stem
C. Coordinates muscular activity.
4) _____ Frontal lobe
D. Responsible for vision
5) _____ Parietal lobe
E. Responsible for hearing and language comprehension
6) _____ Occipital lobe 7) _____ Temporal lobe
F. The part of the diencephalon that controls the endocrine system and regulates appetite, thirst, and body temperature
8) _____ Hypothalamus 9) _____ Corpus callosum
G. Responsible for body sense
10) _____ Ventricles
H. Responsible for motor function, behavior, emotions, and thinking I. Controls vital functions like breathing and heart rate. J. The largest part of the brain; divided into left and right hemispheres
Short Answer/Essay 11–13. List the three portions of the brain stem. (3 points) ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ Fill in the Blank 14) The grooves on the surface of the brain are called _____. 15) The ridges on the surface of the brain are called _____. 16) The left side of the brain controls the _____ half of the body. 15
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17) The grey matter on the surface of the brain is called the _____. 18) The _____ system consists of nuclei that are involved in mood, memory, and emotion. Multiple Choice 19) Which cranial nerve is responsible for transmitting smell information? A) Olfactory B) Optic C) Vestibulocochlear D) Abducens 20) Which cranial nerve is responsible for transmitting visual information? A) Olfactory B) Facial C) Optic D) Trigeminal 21) Which cranial nerve transmits information about hearing and balance? A) Hypoglossal B) Vagus C) Vestibulocochlear D) Accessory 22) Which cranial nerve controls chewing? A) Optic B) Trigeminal C) Vagus D) Vestibulocochlear 23) Which cranial nerve is responsible for autonomic motor control of the internal organs? A) Vestibulocochlear B) Abducens C) Hypoglossal D) Vagus 16
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24) The primary motor cortex is located in the: A) frontal lobe. B) parietal lobe. C) occipital lobe. D) brain stem. 25) The primary somatic sensory cortex is located in the: A) frontal lobe. B) parietal lobe. C) occipital lobe. D) brain stem. 26) This disease is characterized by resting tremors, slow movement, and “cogwheel” rigidity: A) Cerebral palsy B) Multiple sclerosis C) Parkinson’s disease D) Alzheimer’s disease 27) This disease is characterized by progressive memory loss and dementia: A) Parkinson’s disease B) Alzheimer’s disease C) Lou Gehrig’s disease D) Huntington’s disease 28) When a child exhibits a permanent, nonprogressive set of motor deficits, this is called: A) multiple sclerosis. B) hydrocephalus. C) cerebral palsy. D) Alzheimer’s disease.
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ANSWER KEY Chapter 10—Worksheet 1) J 2) C 3) I 4) H 5) G 6) D 7) E 8) F 9) A 10) B 11–13) medulla oblongata; pons; midbrain 14) sulci 15) gyri 16) right 17) cortex 18) limbic 19) A 20) C 21) C 22) B 23) D 24) A 25) B 26) C 27) B 28) C 18
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Name _________________ LABELING ACTIVITY INSTRUCTIONS: Please label the following diagram.
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LABELING ACTIVITY ANSWER KEY
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Colbert A&P 3E IRM, Ch 11
Chapter 11 THE SENSES: THE SIGHTS AND SOUNDS
LEARNING OUTCOMES Distinguish between general and special senses. Describe the process of seeing. Describe the external and internal anatomy and functions of the eye. Describe the external and internal anatomy and functions of the ear. Explain the process of hearing. Discuss the process involved with the senses of taste, smell, and touch. Contrast the types of pain and the pain response. Explain several common disorders of the eye and ear.
MULTIMEDIA FOUND ON THE POWERPOINT LECTURE OUTLINE 1. Ophthalmic Mediations and their Delivery Video (slide 26) 2. Eye Anatomy Animation (slide 41) 3. Middle Ear Animation (slide 52) 4. Adolescent Ear Animation (slide 53) 5. Child's Ear Animation (slide 54) 6. Tympanic Membrane Thermometer Measurements Video (slide 68) 7. Heat Therapy Video (slide 80) 8. Cold Therapy Video (slide 81) 9. Conjunctivitis Video (slide 89) 10. Cataracts Video (slide 92) 11. Otitis Media Video (slide 104) 12. Audiologists Video (slide 105) 13. Ophthalmologists and Opticians Video (slide 106) 1
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LECTURE OUTLINE I. Types of Senses A. All input from the environment must be taken in by the senses and interpreted by the brain to be understood and appreciated. B. Senses that gather sensory input are also protective in nature and need to be highly integrated with the quick-response nervous system for our survival. C. Special senses include: 1. Sight (eyes) 2. Sound and equilibrium (ears) 3. Smell (nose) 4. Taste (tongue) D. The additional general senses of heat, cold, pain, nausea, hunger, thirst, and pressure or touch and are important to our survival. 1. Cutaneous senses: skin receptors 2. Visceral senses: nausea, hunger, thirst, and the need to urinate and defecate E. Senses monitor and detect changes in the environment, sending this information to the brain via sensory (afferent) neurons. F. The brain interprets the information and makes the appropriate motor, or efferent, response. G. ESP is a controversial sense that means senses outside the normal sensory perception. Debate about its existence continues. II. Sense of Sight A. The External Structures of the Eye 1. Orbit: cone-shaped cavity formed by the skull; it houses and protects the eyeball. 2. Muscles connect the eyeball to the orbit and allow rotary movement. 3. The eyelids a. Close over the eye to protect it from light, foreign particles, and impact injury. b. Eyelashes in the eyelid help to prevent gross particles from entering the eye. c. Contain sebaceous glands. 4. Conjunctiva: protective membrane over the exposed surface of the eyeball that acts as a protective covering 2
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5. The lacrimal apparatus a. Produces and stores tears; tears are antiseptic to help reduce infections. b. Contains the lacrimal gland and its corresponding ducts. B. Internal Structures of the Eye 1. Two chambers of fluid that help to protect the eye. The fluids of the eye are called humors. a. Aqueous humor is watery; bathes the iris, pupil, and lens; fills the anterior and posterior chambers. b. Vitreous humor is a clear, jellylike fluid that occupies the entire cavity behind the lens. 2. The eye has three layers: a. Sclera i. The outermost layer, a tough fibrous tissue that serves as a protective shield ii. Contains the cornea, transparent to allow light to pass through, and curved to bend the entering light to focus it on the retina. b. Choroid i. The middle layer, a highly vascularized and pigmented region that provides nourishment to the eye ii. Contains the iris and the pupil: a. Iris: the colored portion of the eye i. Controls the size of the opening (pupil) where light passes into eye. ii. Sphincter that can relax or contract: relaxes in low light; contracts in bright light. b. Pupil: the opening c. Lens and ciliary muscles: Muscles accommodate by altering the shape of the lens, making it thinner or thicker to allow the incoming light rays to focus on the retinal area. c. Retina i. A delicate membrane that continues posteriorly and joins the optic nerve. 3
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ii. Contains two types of light-sensing receptors called rods and cones: a. Rods are active in dim light and do not perceive color. b. Cones are active in bright light and perceive color. iii. Receptors contain photopigments that cause a chemical change when light hits them, causing impulses to be sent to the optic nerve. III. The Sense of Hearing A. The ear is responsible for hearing and maintaining equilibrium, or sense of balance. B. Sound vibrations are received usually via the air and translated into an interpretable sound via the eighth cranial nerve. C. Structures of the Ear 1. External Ear a. The outer projection—the part we can see—called the pinna or auricle b. Canal leading into the middle ear, called the auditory canal or external auditory meatus c. Earwax, called cerumen, secreted by the ceruminous glands to lubricate and protect the ear d. Eardrum, or tympanic membrane, at end of canal where the external ear ends 2. Middle Ear a. Also called tympanic cavity; contains three small bones, or ossicles. i. Bones of the ear are named according to their shape ii. Hammer, or malleus, is attached to the tympanic membrane. iii. Anvil, or incus, is attached to the hammer. iv. Stirrup, or stapes, connects to a membrane called the oval window that begins the inner ear. b. Ossicles are joined so they can amplify the sound waves the tympanic membrane receives from the external ear; ossicles can amplify sound up to 22 times the original level. c. Once amplified, sound waves are transmitted to the fluid in the inner ear d. Eustachian tubes i. Allow air pressure on either side of the eardrum to be equalized. 4
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ii. Connect the nose and throat to the middle ear. iii. Equalization of pressure allows eardrum to vibrate freely with incoming sound waves; sudden pressure changes, as when flying in an airplane, can affect this area and cause ears to “pop.” 3. The Inner Ear a. Oval window transmits sound waves into the inner ear. b. Inner ear is divided into three separate, hollow, bony spaces that form a maze, or labyrinth—also called bony labyrinth. c. Three areas include the cochlea, the vestibule chamber, and the semicircular canals. d. Cochlea is responsible for sense of hearing. i. A bony spiral or snail shell–shaped entrance to the internal ear ii. Connected to the oval window membrane iii. Contains fluids called perilymph and endolymph, which help transmit the sound. iv. Sound is carried to tiny, hairlike receptors that are stimulated and conduct the signal to the brain via the vestibulocochlear nerve. e. Also in the inner ear are the semicircular canals that contain sensory input related to equilibrium. 4. Hearing Summarized a. Sound waves enter the external canal and vibrate the eardrum, or tympanic membrane (sound conduction). b. The middle ear then amplifies the sound through the respective ossicles (bone conduction of sound). c. The stapes vibrates and causes a gentle pumping against the oval window membrane. This causes cochlear fluid to vibrate small, hairlike neurons found in an area called the organ of Corti. d. As a result of the vibration, sensory cells send a nerve impulse to the temporal lobe of the brain, where it is interpreted as sound (sensorineural conduction). 5. Balance a. Ear is responsible for the sense of balance (equilibrium). b. Semicircular canals process sensory input related to equilibrium. i. Nerve endings (receptors) in the form of hair cells line the semicircular 5
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canals. ii. Canals form three loops filled with endolymph that shifts when the body changes position. iii. Sensory receptors pick up movement, triggering a nerve impulse to travel to the brain stem and the cerebellum, where it's interpreted as body position to help maintain muscle coordination and body equilibrium. iv. Vertigo: the sensation of moving around in space or the illusion of objects moving around the person caused by a variety of disorders. IV. Other Senses A. Taste 1. The sense of taste is called the gustatory sense. 2.
Bumps (papillae) cover the tongue and contain taste receptors (taste buds). a. They are also found on the lips, palate, and inner cheeks.
b. Die off and are replaced regularly, but this process slows down as we age, diminishing our sense of taste. 3. Taste buds send signals to the brain via three distinct cranial nerves. a. One nerve detects the anterior two-thirds of the tongue. b. A second nerve detects the posterior portion of the tongue. c. A third nerve detects the throat area. 4. The five tastes are sweet, sour, salty, bitter, and umami (the taste of glutamates). 5.
Taste preferences change with the body’s needs.
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Refinement of food taste is primarily dependent on the sense of smell.
B. Smell 1. The sense of smell arises from the receptors located in the olfactory region or the upper part of the nasal cavity. 2. We “sniff” to bring the smell into the area where it can be interpreted. 3. Taste and smell are closely related, and pleasant food odors initiate digestive enzymes. 4. Smell is also closely linked to memory, possibly because the temporal lobe of the brain processes smells, memories, and emotions. C. Touch 1. Touch receptors are small, rounded bodies called tactile corpuscles located in the skin, 6
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especially concentrated in the fingertips and the tip of the tongue. 2. Temperature a. Temperature sensors (thermoreceptors) are also located in the skin, with separate sensors for heat and cold. b. Adaptation occurs when sensory stimulation is continually applied, changing the body’s perception of temperature. i. Thermoreceptors stop being stimulated once the surface temperature of your skin drops to below 40 degrees Fahrenheit and when it rises over 113 degrees Fahrenheit. ii. At this point, pain receptors then take over to help avoid getting burned. 3. Pain 1. Pain is a very important protective sense, the body’s way of making us pay attention to danger. 2. Pain is the most widely distributed sense, found in skin, muscle, joints, and internal organs. 3. Pain receptors are branching nerve fibers called free nerve endings or nociceptors. 4. Types of pain a. Referred pain: Originates in an internal organ and is felt in another region of the skin. Example: Liver and gallbladder pain may be felt in the right shoulder. b. Phantom pain: pain felt in an area that no longer exists, such as following an amputation 5. Pain receptors a. Pain receptors do not adapt; you feel pain as long as the stimulus is there. b. Pain threshold is probably different in different individuals. VII. Common Disorders of the Eye and Ear A. Disorders of the eye 1. Conjunctivitis: inflammation of membrane that lines the eye; can be acute or chronic, caused by pathogens or irritants, and is sometimes called pink eye. 2. Cataract: clouding of the lens; incidence may increase with increased exposure to sunlight. a. Untreated, can lead to blindness. b. Cataract surgery was one of the earliest surgical procedures, dating back to ancient Greece. 7 .
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3. Glaucoma: increased pressure in the fluid of the eye, which interferes with optic nerve function; occurs in 20% of adults over 40, and 15% result in blindness; called the "silent thief of sight." 4. Hyperopia: Objects up close appear blurred (farsightedness). 5. Presbyopia: Occurs when the ciliary muscles age, causing weakness, and pupil size decreases, reducing light coming into the retina and resulting in farsightedness. 6. Myopia: Objects at a distance appear blurred (nearsightedness). 7. Amblyopia: also called a lazy eye; occurs in childhood; results in poor vision because one eye does more work than the other. 8. Diagnosing other problems using the eye a. Condition of the eyes can help in diagnosis of a variety of nonvisual diseases. b. Yellow tint to the conjunctiva (jaundice) can indicate liver disease. c. REM (rapid eye movement) is a stage of sleep and can be measured in sleep studies to help diagnose sleep disorders. d. Responsiveness of the pupil to light can help diagnose neurological problems (PERRLA). B. Disorders of the ear 1. Otitis media: infection of the middle ear; commonly associated with an upper respiratory infection (URI), such as a cold 2. Labyrinthitis: inflammation of the inner ear, often caused by high fevers, resulting in vertigo 3. Ménière’s disease: a chronic inflammation that affects the labyrinth and leads to progressive hearing loss and vertigo 4. Deafness: partial or complete hearing loss caused by many conditions ranging from inflammation or scarring of anything from the tympanic membrane to the auditory nerve 5. Tinnitus: ringing in the ear, sometimes caused by taking too much aspirin
CLASSROOM ACTIVITIES 1. Ask students to discuss common sense. Is it part of the sensory system? What about extrasensory perception (ESP)—is that a special sense? Does it really exist? 8
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2. Divide the class into two groups. Have one group blindfold themselves and the other group act as guides, leading the blindfolded students around the classroom or corridors. Give both groups an opportunity to experience blindness. Next, have one group wear headphones or earplugs to experience hearing loss, while the other group tries to talk to them. Then have the groups exchange roles. Finally, hold a discussion about caring for patients with sensory loss and what it was like to experience these losses, even temporarily. Ask how the method they use to care for patients will change based on these experiences. 3. Have students use nose plugs to block their sense of smell. Then blindfold them and ask them to identify various foods. Make sure to determine there are no food allergies before doing this experiment. Use foods such as bananas, peanut butter, and broccoli—foods with distinctive tastes. Also ask students to distinguish between food with similar textures but different flavors, such as apple and raw potato. TEACHING STRATEGIES 1. Have students trace the passage of an image through the various components of the eye, to the brain, discussing where images are decoded in the brain and how these decoded images give us a sense of our surroundings. Talk about perceptions, and use optical illusions to demonstrate how perception creates reality. For instance, hold up the FedEx logo for the class to look at for a few minutes. Then ask them to find the arrow in the image. Discuss how you must look at the logo differently to find that arrow and how most people have never seen it. 2. Discuss the sense of isolation that can come from hearing loss in the elderly. Ask students to think about times when they were in a group, and two people in the group were whispering back and forth. Didn’t they feel isolated? How would it feel to live in a world where you couldn’t read lips and had no idea what people were saying to one another? How does that affect patient care, especially when caring for the elderly? 3. Make students aware of the increase in hearing loss in young people because of playing loud music or while listening to loud music while wearing headphones or ear buds. Discuss the value of enjoying music at loud levels versus the value of their ability to hear. 4. Demonstrate eye tests like the Ishihara color blindness chart or the Snellen distance chart—pediatric, illiterate, and adult. FACTOIDS 1. Excessive exposure to loud noise can damage the tiny hairs in the cochlea and lead to hearing loss. Generally, this type of hearing loss is reversible, except in cases of very loud noises. However, repeated exposure can cause permanent damage and hearing loss, known as noise-induced hearing loss. Seventeen percent of middle and high school students have some degree of hearing loss, mostly in higher pitches. Those who attend frequent concerts have an even higher rate of hearing loss. One student studied showed hearing impairment after listening to high-intensity rock music for 88 hours in a 2-month span, whereas a protected left ear showed no change. The damage to the right ear was permanent. 9
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2. The leading cause of blindness in the United States is primarily age-related eye diseases like glaucoma and macular degeneration, diabetic retinopathy, and cataracts. Legal blindness is defined as visual acuity with best correction of worse than or equal to 20/200. 3.
Synesthesia is a condition in which two or more of a person's special senses become intertwined. For example, a person might taste color or see sound. Mirror-touch synesthesia is a condition in which one who watches another person being touched experiences the same tactile sensation on one’s own body, without actually being touched.
ETHICAL DILEMMAS 1. You’re riding in a car with a friend who has a really powerful stereo system. Being a medical professional, you know that you are risking your hearing if you listen to music at the level your friend likes to play it. What do you do? 2. Suppose you attend school with a person suffering from a sensory loss, such as blindness or deafness. Should that person with a disability be given special allowances? Relate the story of Helen Keller (blind, deaf, and mute), who graduated from Radcliffe University by having her assistant/teacher spell out all her textbooks into her hand.
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ANSWERS TO TEST YOUR KNOWLEDGE Test Your Knowledge 11–1 Answers, p. 218 1. a 2. c 3. d 4. b 5. b 6. c Test Your Knowledge 11–2 Answers, p. 223 1. c 2. c 3. pinna 4. cerumen 5. hammer 6. incus 7. stapes 8. vertigo ANSWERS TO THE CASE STUDY, P. 229 1. The patient has ringing in his ears and is dizzy and sick to his stomach. He is having trouble hearing as well. 2. Ménière’s disease 3. His inner ear is affected. We can tell that because he is dizzy, which suggests the semicircular canals as well as the cochlea are affected. ANSWERS TO REVIEW QUESTIONS, P. 229–230 Multiple Choice 1. c, 2. a, 3. b, 4. b, 5. d, 6. b, 7. a Fill in the Blank 1. hearing; balance 11
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2. malleus; incus; stapes or hammer, stirrup and anvil 3. cone 4. gallbladder or liver 5. cataracts Short Answer 1. Special senses are senses found in particular regions of the body and usually have an organ associated with them. For example, vision is associated with the eye. General senses such as touch are more scattered throughout the body. They do not have a particular organ associated with them. 2. The five basic tastes are bitter, sweet, salt, sour, and umami. Taste is very dependent on smell. Many foods have very little taste and can only be recognized by the sense of smell. 3. Adaptation occurs when a sensory receptor gets used to a signal. For example, heat and cold receptors get used to a particular temperature when they have been at that temperature for a while. That’s why washing your hands in lukewarm water feels like hot water if you have been outside for a while in the cold. 4. Light rays pass through the cornea, are partially focused by the curvature of the cornea, and then pass through the pupil into the eye. The lens, which can change shape, further focuses the light rays. If the eye is functioning properly, the light is focused on the macula lutea of the retina, the place of sharpest focus. Rods and cones react to the light and send the information down the optic nerves. The information eventually reaches the primary visual cortex and visual association areas in the occipital lobe of the brain. 5. Sound waves enter the external canal and vibrate the tympanic membrane. Ossicles in the middle ear (attached to the tympanic membrane) amplify the sound. The movement of the bones against the window causes vibration of the fluid in the inner ear, which causes the vibration of hair cells (sensory neurons). Nerve impulses are sent to the temporal lobe of the brain via the vestibulocochlear nerve (VIII). 6.
Glaucoma is known as the “silent thief of sight” because it can often go undetected and lead to blindness. It is caused by increased pressure in the fluid of the eye, which interferes with optic nerve functioning. Glaucoma occurs in 20 percent of adults over age 40 and accounts for 15 percent of the cases of blindness in America. This is a tragic loss because glaucoma can be readily diagnosed and treated.
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Name ______________ CHAPTER 11—WORKSHEET Matching Please match each structure of the eye with the appropriate description. 1) _____ Iris
A. The sensory receptors that can perceive color
2) _____ Pupil
B. The cone-shaped cavity in the skull that houses and protects the eyeball
3) _____ Sclera 4) _____ Cornea
C. A watery fluid that fills the front part of the eyeball
5) _____ Aqueous humor
D. The sensory receptors that function in dim light
6) _____ Vitreous humor 7) _____ Retina
E. Produces tears.
8) _____ Rods
F. Carries sensory information from the eye to the brain.
9) _____ Cones
G. A protective membrane that covers the exposed surface of the eyeball
10) _____ Conjunctiva 11) _____ Optic nerve
H. The innermost layer of the eye; contains sensory receptors for vision.
12) _____ Lens 13) _____ Orbit
I. The colored portion of the eye that controls the size of the pupil
14) _____ Lacrimal gland
J. The white, outer coating of the eyeball
15) _____ Ciliary muscles
K. A jellylike fluid that fills the entire eye cavity behind the lens L. A specialized portion of the sclera at the front of the eye that is clear and allows light to enter the eye M. The opening in the center of the iris that lets in light N. Control the thickness of the lens to help focus light on the retina. O. A clear disk inside the eye that focuses light on the retina 13
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Multiple Choice 16) Which of the following is an example of a special sense? A) Vision B) Temperature C) Pain D) Pressure 17) Which of the following is an example of a visceral sense? A) Vision B) Nausea C) Touch D) Hearing 18) The olfactory receptors are located in the: A) eyes. B) nose. C) skin. D) internal organs. 19) Nociceptors are the sensory receptors for: A) pain. B) temperature. C) pressure. D) smell.
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Matching Please match each structure of the ear with the appropriate description. 20) _____ Pinna
A. The eardrum; separates the external ear from the middle ear.
21) _____ Auditory canal 22) _____ Tympanic membrane
B. The place where the ossicles touch the cochlea
23) _____ Ossicles
C. The outer, visible portion of the ear
24) _____ Stapes
D. The portion of the inner ear involved in the sense of equilibrium
25) _____ Malleus
E. The tube that carries sound to the eardrum and contains glands that produce earwax
26) _____ Oval window 27) _____ Cochlea
F. Connects the middle ear to the throat and helps equalize middle ear pressure.
28) _____ Semicircular canals 29) _____ Eustachian tube
G. The bone that touches the oval window 30) _____ Perilymph H. A set of three tiny bones that amplify and transmit sound vibrations I. The fluid found inside the inner ear J. The bone that touches the eardrum K. The portion of the inner ear that detects sound ANSWER KEY Chapter 11—Worksheet 1) I 2) M 3) J 4) L 5) C 6) K 7) H 15
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8) D 9) A 10) G 11) F 12) O 13) B 14) E 15) N 16) A 17) B 18) B 19) A 20) C 21) E 22) A 23) H 24) G 25) J 26) B 27) K 28) D 29) F 30) I
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Name ______________ LABELING ACTIVITY INSTRUCTIONS: Please label the following diagram.
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LABELING ACTIVITY ANSWER KEY
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Chapter 12 THE ENDOCRINE SYSTEM: THE BODY’S OTHER CONTROL SYSTEM
LEARNING OUTCOMES Describe the purpose and effects of hormones within the body. Explain the difference between a hormone and a neurotransmitter. Explain how hormones work. Describe the control of endocrine activity within the body, including homeostasis, negative feedback, and the three mechanisms of control of hormone levels. Discuss the location and function of major endocrine organs and glands, including the hypothalamus, pituitary gland, thyroid gland, thymus gland, pineal gland, pancreas, adrenal glands, and gonads. Discuss common disorders of the endocrine system.
MULTIMEDIA FOUND ON THE POWERPOINT LECTURE OUTLINE 1. Hyperglycemia Animation (slide 73) 2. Hypoglycemia Animation (slide 74) 3. Pathology of Diabetes Video (slide 80) 4. Insulin Video (slide 81) 5. Hypothalamic Pituitary Axis Animation (slide 82) 6. Monitoring Glucose Levels Video (slide 83) 7. Aging and the Endocrine System Video (slide 117) 8. Phlebotomy Video (slide 118) 9. Dieticians Video (slide 119)
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LECTURE OUTLINE I. Organization of the Endocrine System A. The endocrine system works with nervous system. B. The endocrine system is a slower, more subtle control system. C. Although the endocrine system acts slowly, the effects last longer than those of the nervous system. II. Endocrine Organs and Glands A. Organs and glands that secrete chemical messengers into the bloodstream 1. A gland is an organized cluster of cells or tissues whose sole function is to manufacture a substance that is either secreted from or used within the body. 2. Organs are collections of more than one type of specialized tissues that may be able to secrete substances but also have additional functions. B. Exocrine glands secrete out of the body, like sweat glands, and are not part of endocrine system. C. Many glands, such as the hypothalamus and pancreas, have multiple functions. D. Organs such as the heart, small intestine, and stomach can also secrete hormones; however, they are not primary endocrine organs. III. Hormones A. The chemical messengers released by endocrine glands B. Released into the bloodstream and travel all over the body, some affecting millions of cells simultaneously C. Hormones’ effects last for minutes or even hours, or possibly days. D. Many hormones are secreted continuously, with the amount secreted changing as needed. E. How Hormones Work 1. Work by binding to receptors on target cells. a. They bind to sites outside the cell, like neurotransmitters, and to sites inside the cell. 2. Extracellular: Bind to receptors on cell surface. a. Mainly modified amino acids, polypeptides, or proteins 2
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b. Change permeability, changing enzyme activity inside cell. 3. Intracellular: Bind to receptors inside cell. a. Examples: steroids and thyroid hormones b. Interact with DNA to change cell activity, very potent, carefully regulated. c. Tightly regulated in body 4. Prostaglandins a. Short-range hormones b. Use paracrine signalling. c. Functions differ based on site of production. 5. Hormone names a. Most hormones are named according to location or function. b. If you learn the meanings of their names, you can usually tell something about the hormone. c. Most hormones are known by their abbreviations because their names are long. IV. Control of Endocrine Activity A. Many endocrine organs secrete hormones continuously. B. Homeostasis and Negative Feedback 1. Hormone activity is related to homeostasis. 2. Most hormones have a set point that is that is the ideal level for that particular value. 3. The body’s control systems (endocrine and nervous system) work to keep levels at or near ideal. a. Negative feedback counteracts a change. If hormone levels rise, negative feedback will turn off the endocrine organ that is secreting the hormone when set point is achieved. b. The body is also capable of positive feedback, which increases the magnitude of a change (vicious cycle). i. This is not a way to regulate the body, since positive feedback increases a change away from set point. E. Sources of Control of Hormone Levels 1. Endocrine organs function in three basic ways to maintain hormone levels or body 3
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function: (neural control), by other hormones (hormonal control), or by body fluids such as the blood (humoral control). 2. Neural Control a. Some hormones are directly controlled by the nervous system. b. Example: sympathetic control of adrenal gland 3. Hormonal Control a. Hierarchy of hormonal control: One gland is controlled by the release of hormones from another gland up the chain, etc. b. Orders are sent from one organ to another, as in a relay race. c. Negative feedback controls the flow of orders via hormones from one part of the chain to the other. d. Example: pituitary control of adrenal gland 4. Humoral Control a. Some endocrine organs directly monitor the body’s internal environment by monitoring the body fluids and respond accordingly. b. Humoral pertains to body fluids or substances—hence the name humoral control. c. Example: pancreatic control of blood glucose V. Major Endocrine Glands A. The Hypothalamus 1. Located in the diencephalon, is an important link between the two control systems. 2. Controls much of the body’s physiology, including hunger, thirst, fluid balance, and body temperature. 3. Controls the pituitary gland and thus most other glands in the endocrine system. B. The Pituitary 1. The pituitary is also a part of the diencephalon. 2. Called the “master gland” because of its role in controlling other endocrine glands 3. Acts mainly under orders from the hypothalamus. 4. The pituitary is split into two segments: the posterior pituitary and the anterior pituitary. 4 .
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1. Posterior pituitary (Neurohypophysis) a. The posterior pituitary is an extension of the hypothalamus. b. Hypothalamic neurons specialized to secrete hormones instead of neurotransmitters extend their axons through a stalk in the posterior pituitary. c. These neurons secrete two hormones: antidiuretic hormone (ADH) and oxytocin. d. Although these hormones are secreted by the pituitary, they are made by the hypothalamus. i. ADH a. Decreases urination, which decreases fluid lost, increasing body fluid volume. b. ADH is secreted when the hypothalamus senses decreased blood volume or increased blood osmolarity (solids suspended in blood). c. ADH circulates through the bloodstream and targets the kidneys specifically, causing them to absorb more water. d. ADH is very important in long-term control of blood pressure, especially during dehydration. e. Caffeine and alcohol turn off ADH production. ii. Oxytocin a. Oxytocin is important in maintaining uterine contractions during labor and is involved in milk production in nursing mothers. b. Oxytocin function in males is unknown. 2. The Anterior Pituitary (Adenohypophysis) a. The anterior pituitary makes and secretes a number of hormones under hormonal control of the hypothalamus (with the exception of growth hormone). b. Pituitary hormones usually control the secretion of hormones by another endocrine gland. C. The Thyroid Gland A. Located in the anterior portion of the neck and is butterfly-shaped. B. Hormones secreted 1. Thyroxine (T3) and Triiodothyronine (T4) 5
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a. Secreted under pituitary orders b. Control cell metabolism and growth. c. Contain iodine. d. Clinically important; too little or too much can cause serious symptoms. 2. Calcitonin, involved in calcium storage 3.
Posterior surface includes parathyroid glands.
a. Embedded in posterior surface of thyroid gland b. They produce parathyroid hormone (PTH), which regulates the levels of calcium in the bloodstream. c. If calcium levels get too low, the parathyroid glands are stimulated to release PTH, which stimulates bone-dissolving cells and releases calcium into the bloodstream. D. The Thymus Gland 1. The thymus gland is located in the upper thorax. 2. It plays an important function in the immune system. 3. It produces a hormone called thymosin, which helps with the maturation of white blood cells during childhood to fight infection. E. The Pineal Gland 1. In diencephalon 2. Its full function remains unknown. 3. Produces the hormone melatonin; may trigger sleep by peaking at night and causing drowsiness. F. The Pancreas 1. Responsible for maintaining blood sugar levels at or near a set point of 70–105 mg/dL (milligrams per deciliter) 2. When blood sugar rises, the pancreas releases insulin. 3. When blood sugar drops, the pancreas releases glucagon. 4. Glucose levels affect cells: a. Cellular respiration by making ATP b. Fluid balance 6
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5. Diabetes mellitus (DM) a. Characterized by abnormally high blood glucose levels b. Type 1 diabetes (insulin-dependent diabetes mellitus, IDDM, juvenile onset) i. Caused by destruction of insulin-producing cells of the pancreas ii. Requires daily insulin injections. c. Type 2 diabetes (non-insulin-dependent diabetes mellitus, NIDDM, late onset) i. Caused by insensitivity of the body’s tissues to insulin ii. Can sometimes be treated with a carefully controlled diet and a weight loss regimen. d. In both types of DM, elevated blood sugar must be controlled. i. High glucose levels cause the kidneys to work overtime to secrete the excess sugar. ii. Increased urination (polyuria), dehydration leading to increased thirst (polyhydramnios), and hunger are the most common symptoms. iii. Weight loss as the body searches for other sources of energy. iv. Acid is produced because of abnormal metabolism; blood acidity worsens, leading to tissue and organ damage. v. Lack of treatment leads to coma and death. G. The Adrenal Glands 1. Pair of small glands that sit on the kidneys like baseball caps 2. Two regions: 1. The adrenal cortex is the outer layer. a. Adrenal cortex makes dozens of steroid hormones known collectively as adrenocorticosteroids, released under the direct stimulation of the anterior pituitary. b. Many of these hormones are so important that a decrease in production could be fatal relatively quickly. c. Each of these hormones has a specific function, including regulation of fluids, electrolytes, blood sugar, reproduction, secondary sex characteristics, cell metabolism, growth, and immune system function. 3. Adrenal medulla is the middle of the gland. 7
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a. Adrenal medulla releases two hormones: i. Epinephrine (also known as adrenalin) ii. Norepinephrine (both a hormone and a neurotransmitter) b. These hormones increase the duration of the effects of the sympathetic nervous system; effects of hormones last longer than a neurotransmitter. c. Effects include increased heart rate, blood pressure, and respiration along with profuse sweating and dry mouth. 4. The Adrenal Cortex a. Makes dozens of steroid hormones known collectively as adrenocorticosteroids. b. Released under direction of anterior pituitary c. Many steroid hormones are so important that a decrease in their production could be fatal relatively quickly. d. Functions of steroids include: i. Regulate electrolyte and fluid balance (mineralocorticoids). ii. Regulate blood sugar (glucocorticoids). iii. Regulate reproduction and secondary sexual characteristics. iv. Control cell metabolism, growth, and immune system function. H. Gonads 1. The gonads include: 1. Testes (male) 2. Ovaries (female) 2. Their chief function is to produce and store gametes. a. Eggs b. Sperm 3. They also produce a number of sex hormones that control reproduction. a. Testosterone in men b. Estrogen in women XIV. Common Disorders of the Endocrine System A. Anabolic steroid abuse 1. Anabolic steroids cause large increase in muscle mass. 8
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2. Some athletes use them to increase performance or to enlarge muscles faster than they can by only working out. 3. Numerous side effects B. Syndrome of inappropriate antidiuretic hormone secretion (SIADH) 1. Characterized by severe hyponatremia (low blood sodium), usually due to overproduction of ADH 2. Leads to fluid retention and very dilute plasma, leading to dangerously low sodium levels in the blood. 3. Causes include pulmonary disease, cancer, some medications, and central nervous system disorders, traumatic brain injury (TBI). C. Hashimoto’s disease 1. Hypothyroidism resulting from autoimmune attack of the thyroid gland 2. The cause is unknown. 3. The thyroid may swell, causing painful swallowing. 4. It is most common in women between 30 and 50 years old and is treated with daily synthetic hormones D. Congenital hypothyroidism 1. Babies do not produce enough thyroid hormone. 2. Can cause developmental disabilities, but treatable with hormone injections. 3. Relatively common; babies in United States tested E. Graves’ disease 1. Hyperthyroidism resulting from autoimmune attack on thyroid gland 2. Symptoms include insomnia, bulging eyes, and jitteriness. 3. Treatment involves decreasing hormone secretion by destroying the thyroid with radioactive iodine; surgery is indicated if treatment is not effective. 4. After treatment, synthetic thyroid hormone is necessary because the thyroid no longer functions properly, if at all. F. Pheochromocytoma 1. A pheochromocytoma is a tumor of the adrenal gland that causes increased epinephrine secretion. 9
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2. Symptoms are similar to an adrenaline rush, including severe headaches, excessive sweating, racing heart, anxiety, abdominal pain, heat intolerance, and weight loss. 3. They are rarely cancerous but must be removed or the effects of excessive epinephrine production will be fatal. G. Addison’s disease 1. Addison’s disease is caused by insufficient production of the adrenocorticosteroid cortisol. 2. The deficiency causes weight loss, muscle weakness, fatigue, low blood pressure, and excessive skin pigmentation. 3. Aldosterone may also be deficient. 4. Many causes of Addison’s are autoimmune. 5. It is treated with hormone replacement. H. Cushing syndrome 1. Cushing syndrome is caused by oversecretion of cortisol. 2. Symptoms include upper body obesity, round face, easy bruising, weakened bones, fatigue, high blood pressure, and high blood sugar. 3. Women may have excessive facial hair and irregular periods; men have decreased fertility and sex drive. 4. It may be a side effect of medical use of steroids, like prednisone, or may be because of primary tumors, lung tumors, adrenal tumors, or one of several genetic disorders. 5. Treatment depends on the underlying cause; hormone replacement may be required. CLASSROOM ACTIVITIES 1. Divide students into groups and assign each group one of the endocrine glands. Have them create a class presentation covering the location of the gland, the hormones it secretes, the function of each hormone, the effect of over- or underproduction of each hormone, and so on. Encourage students to design visual aids and show their creativity. 2. Have students stand in a circle and demonstrate negative and positive feedback by depositing pennies in baskets held by each student. First, they will demonstrate positive feedback by repeatedly dropping pennies into the basket on their left until something turns off the feedback loop. Next, have them demonstrate negative feedback by giving one penny to the person with the fewest pennies until setpoint (or the average number of pennies) is achieved in each basket. 10
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3.
Have students create an "Endocrine System Jeopardy!" game. Divide students into small groups and assign each group a few endocrine glands. Each group should write Jeopardy!style questions and answers about the glands. For example: Topic is Hypothalamic and Pituitary Hormones; question: I make your labor possible; answer: What is oxytocin? Reconvene as a class and play a few rounds.
TEACHING STRATEGIES 1. Discuss the overall role of hormones, glands, and the endocrine system on maintaining homeostasis. Help students to grasp concepts like negative and positive feedback, humoral control, and endocrine control. 2. Once students understand the basics, review the individual glands and their functions. Students need to understand that although we discuss glands individually to help them learn, the glands are all interrelated and work together continuously to keep the body in balance. FACTOIDS 1. The body is in a continuous state of hunger, intermittently relieved by eating. The hypothalamus regulates food intake and controls feelings of hunger and satiety. Some children are unable to control this sense of hunger. They have a genetic disease called Prader-Willi syndrome. The chromosomal deficiency comes from the father, resulting in children who have an insatiable hunger. No matter how much they are fed, children with Prader-Willi syndrome are always hungry. Parents must lock the refrigerator and cabinets to control their eating habits. It is an uncommon disorder, occurring in 1 in 15,000 children. 2. You have over 30 hormones regulating things such as hunger, satiety, sleep, body temperature, the metabolism of food products, weight balance, stress response, energy/activity levels, and growth rate. Each one of these hormones is continuously measuring and reacting to changes in your body. 3.
In the 1600s, English physician Thomas Willis coined the term "mellitus," which is Latin for honey, in reference to a particular type of diabetes, because the urine of patients with this condition tasted sweet.
ETHICAL DILEMMAS 1. Height is largely a product of genetics, in the absence of disease or malnutrition. If Mom and Dad are below-average height, their children are likely to be of below-average height. Some parents were teased mercilessly or picked on by their peers because they were small. They don’t want their children to suffer this fate, so they have growth hormone administered to them. The administration of growth hormone can have many side effects. Is administering growth hormone to children to make them average, or above-average, height a good idea? 11
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2. The use of steroids for performance enhancement in athletes is a controversial issue. The Olympic Committee has all athletes tested for steroid use. Why is use of steroids a problem? If you could make millions of dollars as an athlete in a professional sports league, and all you had to do to succeed was take hormones, would you do it? How can we encourage athletes to value their current and future health over the millions of dollars they could make today? ANSWERS TO TEST YOUR KNOWLEDGE Test Your Knowledge 12–1 Answers, p. 235 1. c 2. c 3. c 4. c 5. b 6. b Test Your Knowledge 12–2 Answers, p. 240 1. c 2. a 3. b 4. a 5. a Test Your Knowledge 12–3 Answers, p. 243 1. c 2. c 3. b 4. a Test Your Knowledge 12–4 Answers, p. 248 1. c 2. d 3. c 12
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4. d 5. a. Type I b. Type II c. Type II
ANSWERS TO THE CASE STUDY, P. 252 1. He has type 2 diabetes (NIDDM). 2. His kidneys will be damaged if he is not treated. 3. A healthier diet and increased exercise may effectively control type 2 diabetes. A number of medications can also decrease his blood glucose if a change in diet is unsuccessful. ANSWERS TO REVIEW QUESTIONS, P. 252–253 Matching 1. f 2. a 3. i 4. e 5. g 6. c 7. j 8. d 9. b 10. h Multiple Choice 1. a, 2. b, 3. c, 4. b, 5. b, 6. d, 7. c Fill in the Blank 1. raises 2. increases or regulates 3. Oxytocin 4. adrenal medulla 13
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5. pituitary; adrenal 6. pituitary or hypothalamus 7. thymosin or growth hormone Short Answer 1. Neurotransmitters are short-lived, short-distance chemical signals secreted by neurons that change the permeability of nearby cells. Hormones are long-lived, long-distance chemical signals secreted by endocrine organs into the bloodstream to travel to distant target cells. 2. Negative feedback is a process that controls hormone levels by preventing the endocrine gland from secreting more hormone when hormones reach the desired levels. As hormone levels rise, feedback causes the gland to decrease hormone production. 3. Anabolic steroids should be banned for performance enhancement because they give some competitors unfair advantages. More important, they are very powerful hormones with serious side effects, including metabolic and immune disorders. The levels of these hormones are so tightly controlled by the body that interfering with them artificially can cause serious problems. 4. Neural control is the control of an endocrine gland by the nervous system. For example, neurotransmitters released by the sympathetic nervous system signal the release of hormones from the adrenal medulla. Humoral control is control of hormone levels by blood chemistry. For example, the pancreas can measure blood glucose levels and secrete insulin when glucose levels are high and glucagon when glucose levels are low. Input from the nervous system is not necessary for humoral control.
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Name __________________________ CHAPTER 12—WORKSHEET Multiple Choice 1) The adrenal gland releases epinephrine after being stimulated by the sympathetic nervous system. This is an example of: A) humoral control. B) neural control. C) hormonal control. 2) Thyroid hormone production is regulated by TSH (a hormone produced by the pituitary). This is an example of: A) humoral control. B) neural control. C) hormonal control. 3) The pancreas monitors blood sugar and adjusts production of its hormones appropriately. This is an example of: A) humoral control. B) neural control. C) hormonal control. 4) Which of the following is not part of the endocrine system? A) Thyroid gland B) Pituitary gland C) Sebaceous gland D) Adrenal gland 5) Hormones produced by the hypothalamus include: A) thyrotropin-releasing hormone (TRH). B) oxytocin. C) prolactin. D) antidiuretic hormone (ADH). 15
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6) Which of the following hormones is not produced by the anterior pituitary? A) Thyroid-stimulating hormone (TSH) B) Adrenocorticotropic hormone (ACTH) C) Growth hormone (GH) D) Antidiuretic hormone (ADH) 7) Alcohol turns off this hormone: A) TSH B) ACTH C) ADH D) GH Worksheet—p. 1 of 3 8) Acromegaly is a result of: A) excess growth hormone secretion. B) excess cortisol secretion. C) deficient growth hormone secretion. D) deficient cortisol secretion. 9) This hormone increases milk production by the breasts: A) ACTH B) Oxytocin C) Prolactin D) FSH 10) TSH is a hormone that stimulates the _____ gland. A) thyroid B) adrenal C) pituitary D) pineal 11) The addition of iodine to table salt helps make sure every person gets enough dietary iodine 16
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to produce _____. A) insulin B) thyroid hormones C) adrenaline D) testosterone 12) This condition, characterized by hyponatremia, develops due to an overproduction of ADH: A) SIADH B) Cushing syndrome C) Graves’ disease D) Addison’s disease
13) This condition develops when antibodies attack the TSH receptors, resulting in increased secretion of T3 and T4: A) Hashimoto’s disease B) Cushing syndrome C) Graves’ disease D) Addison’s disease 14) The thyroid gland is located in the: A) brain. B) abdomen. C) chest. D) neck. Worksheet—p. 2 of 3 Fill in the Blank 15) The chemical messengers released by the endocrine glands are called _____. 16) Hormone effects last _____ than the effects of neurotransmitters. 17) _____ is a powerful class of hormones that can pass through the cell membrane and interact 17
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directly with a cell’s DNA. 18) When a body characteristic becomes abnormal, _____ feedback counteracts the change. 19) The _____ is the part of the brain responsible for controlling the pituitary gland. 20) The _____ gland is also known as the “master gland.” Short Answer 21. Please list three hormones produced by the thyroid gland. Then provide the function for each hormone. __________________________________________________________________________ __________________________________________________________________________ __________________________________________________________________________ Matching Please match each gland with the best description of its function. 22) 23) 24) 25) 26) 27) 28) 29) 30) 31)
_____ Hypothalamus _____ Pituitary _____ Pineal _____ Thymus _____ Thyroid _____ Parathyroid _____ Pancreas _____ Adrenal _____ Ovaries _____ Testes
A. Regulates female characteristics. B. Regulates body metabolism C. Regulates blood sugar. D. Increases blood calcium levels. E. Controls the pituitary gland. F. Helps the body cope with stressful situations. G. Regulates male characteristics. H. Also known as the “master gland” I. Helps white blood cells mature. J. Helps regulate sleep/wake cycles by inducing drowsiness.
Worksheet—p. 3 of 3
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ANSWER KEY Chapter 12—Worksheet 1) B 2) C 3) A 4) C 5) A 6) D 7) C 8) A 9) C 10) A 11) B 12) A 13) C 14) D 15) hormones 16) longer 17) Steroids 18) negative 19) hypothalamus 20) pituitary 21) T3 and T4 stimulate body metabolism; calcitonin decreases blood calcium. 22) E 23) H 24) J 25) I 19
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26) B 27) D 28) C 29) F 30) A 31) G
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Name __________________________ LABELING ACTIVITY INSTRUCTIONS: Please label the following diagram.
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LABELING ACTIVITY ANSWER KEY
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Chapter 13 THE CARDIOVASCULAR SYSTEM: TRANSPORT AND SUPPLY
LEARNING OUTCOMES Identify structures and functions of the cardiovascular system. Explain the cardiac cycle and trace the blood flow through the vessels and chambers of the heart. Explain the coronary circulation. Describe the conduction system of the heart. List the major components of blood and their functions. Discuss the importance of blood typing. Explain the process of blood clotting. Differentiate between arteries, veins, and capillaries. Explain regulation of blood pressure. Explain the relationship of the lymphatic system to the cardiovascular system. Describe various cardiovascular diseases.
MULTIMEDIA FOUND ON THE POWERPOINT LECTURE OUTLINE 1. Chambers of the Heart Video (slide 35) 2. Cardiac Cycle of the Heart Animation (slide 45) 3. Blood Flow through the Atria Animation (slide 46) 4. Atrial Contraction Animation (slide 47) 5. Electrocardiology Video (slide 66) 6. Blood Clotting Animation (slide 112) 7. Head and Neck Animation (slide 139) 8. Abdomen and Trunk Animation (slide 140) 9. Arm Animation (slide 141) 1
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10. Leg Animation (slide 142) 11. Heart Failure Animation (slide 160) 12. Heart Attacks Video (slide 170) 13. Aneurysm Animation (slide 174) 14. Dysrhythmia Animation (slide 179) 15. Angina Video (slide 180) 16. Coronary Artery Disease Video (slide 181) 17. Cardiogenic Shock Animation (slide 182) 18. Septic Shock Animation (slide 183) 19. Sickle Cell Anemia Video (slide 191) 20. Leukemia Video (slide 194) 21. Cardiovascular Technology Video (slide 197)
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LECTURE OUTLINE I. System Overview A. The major components of the cardiovascular system include the heart, blood, and a network of blood vessels. B. Circulation is the movement of blood to and from the heart. Circulation can be split into two systems: pulmonary circulation, from heart to lungs and back, and systemic circulation, from heart to body tissues and back. 1. Arteries carry blood away from the heart and branch into smaller vessels called arterioles, which become capillaries, where nutrients and gases are exchanged; capillaries become venules that enlarge and become veins. 2. Veins differ from arteries because they carry blood back to the heart, have a higher level of carbon dioxide, and have thinner walls; they are more numerous and have a larger capacity. C. The blood vessels transport nutrients and oxygen to the cells in the body while carbon dioxide and waste products of cell’s metabolism are removed. II. Incredible Pumps: Heart A. The heart is actually two pumps working together. B. General Structure and Function 1. The heart is the size of a fist, located slightly left of the center of the chest; the base of the heart is proximal to the head while the apex of the heart is distal. 2. The heart is surrounded by a tough membrane known as the fibrous pericardium. a. Inside the fibrous pericardium is the serous pericardium. b. The parietal layer of the serous pericardium lines the fibrous pericardium. c. The visceral pericardium (epicardium) is fused to the surface of the heart. d. Between the visceral and serous pericardium is a fluid-filled potential cavity called the pericardial cavity. e. The middle layer of the heart wall, the myocardium, is made of cardiac muscle. f. The heart is lined by epithelium, called the endocardium.
3. While the heart is a single organ, it is easier to understand if you think of it as two pumps working together. a. The right side collects blood from the body and sends it to the lungs. b. The left side collects blood from the lungs and sends it to the rest of the body. 3 .
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4. There are four chambers in the heart: a. Two upper chambers are atria. b. Two lower chambers are ventricles. c. Ventricle walls are thicker and more muscular than atrial walls. d. Separation of the right and left sides e. Interatrial septum: Separates atria. f. Interventricular septum: Separates ventricles. 5. Blood vessels and blood flow a. Veins: Bring blood back to heart. i. Superior and inferior vena cavae: from body to right atrium ii. Pulmonary veins: from lungs to left atrium; the pulmonary trunk carries blood from the right ventricle to the lungs. b. Arteries: Take blood from the heart. i. Pulmonary artery: Carries from right ventricle to lungs. ii. Aorta: Carries blood from left ventricle to body. 6. Valves: Prevent blood from flowing backward. a. Atrioventricular (AV) valves: between atrium and ventricle on same side i. Have cusps and chordae tendineae attaching them to papillary muscles. ii. Tricuspid: on right side iii. Bicuspid (mitral): on left side b. Semilunar valves: between ventricles and arteries a. No chordae tendineae b. Pulmonary semilunar valve: between right ventricle and pulmonary artery c. Aortic semilunar valve: between left ventricle and aorta C. Cardiac Cycle 1. Heart movements, the cardiac cycle, are divided into two phases. a. Systole is contraction; chambers are pumping. 4
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b. Diastole is relaxation; chambers are filling. c. Both atria and ventricles undergo systole and diastole, but usually when discussing heart movement, we refer to ventricular activity. 2. Systole a. Right ventricle is full of blood, the heart contracts (systole). a. Pressure builds. b. Pressure closes tricuspid valve and opens semilunar valve. c. Blood leaves right ventricle and enters pulmonary artery. b. Left ventricle is the same, but blood is pumped to body out of the aorta. 3. Diastole a. Right ventricle is empty at end of diastole. b. Right atrium is filling from superior and inferior vena cavae. i. Pressure is higher in filled atrium than in empty ventricle. ii. Pressure is higher in blood vessel than in empty ventricle. iii. Pressure opens tricuspid valve. iv. Pressure closes pulmonary semilunar valve. V. Blood flows from atrium into ventricle, filling it. c. Left side of heart is the same situation, left ventricle is filling. 4. Tracing the flow of blood a. Blood flows from the body to the right atrium via the superior and inferior vena cavae. b. It passes through the tricuspid valve into the right ventricle. c. Blood leaves the right ventricle through the pulmonary valve. d. Blood flows to the lungs via the pulmonary artery, where it is oxygenated. e. From the lungs, blood returns to the left atrium via the pulmonary vein. f. It then passes through the bicuspid or mitral valve into the left ventricle. g. It passes through the aortic valve, into the aorta, to the body. 5
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D. Coronary Circulation 1. A portion of the newly oxygen-enriched blood leaving the heart is diverted from the aorta by the right and left coronary arteries. 2. These arteries continuously divide into smaller branches, forming a web of interconnections known as anastomoses to consistently supply the heart muscle with a rich supply of blood. 3. Regular aerobic exercise increases the density of these blood vessels, and the number of anastomoses increases, as does the number of locations. 4. The right coronary artery provides blood for the right ventricle, posterior portion of the interventricular septum, and inferior parts of the heart. 5. The left coronary artery provides blood to the left lateral and anterior walls of the left ventricle and portions of the right ventricle and interventricular septum. E. The Conduction System: The Electric Pathway 1. Cardiac muscle cells contract on their own (autorhythmicity) and have specialized connections called intercalated discs. 2. Specialized cardiac cells create and distribute electrical current that causes a controlled and directed contraction of the heart. 3. These specialized cells are called nodal cells or pacemaker cells. a. These cells are connected to each other and to the conducting network. b. Nodal cells are divided into two groups: i. Sinoatrial (SA) node Located in the wall of the right atrium, near the entrance of the superior vena cava Generates an electrical impulse at approximately 70–80 impulses per minute. ii. Atrioventricular (AV) node Where the atria and ventricles meet Cells in AV node generate an electrical impulse at a rate of 40–60 beats per minute. iii. SA node sends its impulse to the AV node before the AV node can send a signal; however, the AV node acts as backup if the SA node fails to fire, resulting in a slower heart beat because the AV node fires fewer impulses per minute. 6
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4. Movement of electrical impulses a. Movement of electrical impulse in the myocardium is done by specialized conducting cells. b. Once an electric impulse is generated at the SA node, it travels to the AV node. c. There is a bit of a signal delay, allowing the atria to fill with blood before contraction occurs. d. Once the charge hits the AV node, it travels through the AV bundle, or bundle of His. e. The impulse travels down the right and left bundle branch in the interventricular septum. f. These branches spread across the inner surface of both ventricles. g. The impulse travels into the Purkinje cells to carry the impulse to the contractile muscle cells of the ventricles. h. The contraction begins at the apex, and the wave of contraction smoothly continues up the ventricle, squeezing out all the blood. 5. Electrocardiogram (ECG or EKG) a. Because myocardial contraction is an electrical event, that charge can actually be detected on the surface of the body by using an EKG. b. Normal EKG has three distinct waves representing specific heart actions. i. P wave is first wave, representative of the impulse generated by the SA node and depolarization of the atria before they contract. ii. QRS complex represents the depolarization of the ventricles that occurs right before the ventricles contract. iii. Because of the greater muscle action of the ventricles in relation to the atria, the QRS wave is greater in size than the P wave. iv. T wave represents repolarization of the ventricles, where they rest before the next contraction. v. Repolarization of the atria occurs during the QRS complex but is overshadowed by the ventricular activity. vi. There are set ranges for height, depth, and length of each of the waves, and changes or additions to these parameters are called cardiac arrhythmias or dysrhythmias. 7
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III. Blood A. Blood is a fluid form of connective tissue. B. The amount of blood in the body depends on size and sex; generally, the body contains 4–6 liters of blood, or about 7% to 9% of total body weight. C. Blood has three functions: 1. Transportation: oxygen, nutrients, and hormones, carbon dioxide and other waste products 2. Regulation: pH (levels of acidity or alkalinity) and electrolyte (ion) values, body temperature, and fluid balance 3. Protection: infection (WBCs, antibodies), blood clotting D. Blood composition 1. Plasma a. Yellowish, straw-colored liquid that comprises about 55% of the blood’s volume b. 90% water; the other 10% contains nutrients, salts, oxygen; hormones, etc. c. Proteins are an important group of dissolved substances that include: i. Albumin; Aids in keeping the correct amount of water in the blood. ii. Fibrinogen: needed for blood clotting. iii. Globulins: Form antibodies for protection from infection. 2. Formed elements a. Red blood cells (RBCs) or erythrocytes i. Created by red bone marrow through a process called hemopoiesis because they lack a nucleus to reproduce themselves. ii. Similar to a doughnut in shape iii. Transport oxygen with the aid of an iron-containing red pigment called haemoglobin. iv. Help to transport carbon dioxide from the cells to the lungs for removal. b. White blood cells (WBCs) or leukocytes i. Guard against infection; two main types 8
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ii. Polymorphonuclear granulocytes originate from red bone marrow and include neutrophils, eosinophils, and basophils. a. Neutrophils are most aggressive WBC when bacteria attempt to destroy tissue; ingest invaders through phagocytosis by using lysosomes. b. Eosinophils combat parasitic invasions and a variety of body irritants that lead to allergies. c. Basophils are believed to be involved with allergic reactions; secrete heparin. iii. Mononuclear agranulocytes originate from lymphoid and myeloid tissue. a. Monocytes are found in higher-than-normal amounts when chronic infection occurs. b. Lymphocytes protect from infection by producing antibodies that inhibit or directly attack invaders. c. Thrombocytes, or platelets i. Smallest formed elements, responsible for the blood’s ability to clot ii. Can release serotonin, which can cause smooth muscle constriction and decreased blood flow. IV. Blood Types and Transfusions A. Antigens, substances that stimulate the immune system to produce antibodies B. Antigens are typically foreign proteins introduced into the body through wounds, blood transfusions, and so on. C. Because these were not originally found in the body, they are non-self antigens. D. Self-antigens exist on the cell membrane of every cell. E. The reaction between antigens and antibodies is called the antigen–antibody reaction, which is the basis of the immune response. F. Antibodies often react with the antigens that caused them to form, and the antigens stick together in little clumps; called agglutination. G. Although there are over 50 different antigen types, the main focus in blood typing is on A, B, and Rh antigens. H. Type A blood is very common. 1. Approximately 41% of the American population has type A. 9
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2. “A” represents a specific type of self-antigen found on the cell membrane of the RBCs. 3. If a person is born with type A blood, no antibodies are created to fight it, so there are no anti-A antibodies, but there are anti-B antibodies. I. Type B blood 1. Type B RBCs possess type B self-antigens. 2. The plasma contains anti-A antibodies. 3. If a person with type B blood were given type A blood, anti-A antigens would attack the RBCs and destroy them because they see the cells as foreign material; the antibodies cause agglutination, resulting in serious harm and even death. J. Type AB blood 1. Type AB blood contains both A and B self-antigens. 2. Type AB blood has neither A nor B antibodies in the plasma. 3. Because there are no A or B antibodies, people with type AB blood are called universal recipients because they can accept any type of blood type transfusion. K. Type O blood 1. Type O RBCs contain no A or B antigens, but its plasma contains both A and B antibodies. 2. Type O blood can be given to anyone and people with type O are universal donors. L. Rh factor 1. Special blood antigens were first found in the blood of Rhesus monkeys and were labeled Rh factor. 2. Found in 85% of the white and 88% of the black population of the United States 3. People with this antigen are Rh-positive; people without it are Rh-negative. 4. As a result, people are either A, B, AB, or O negative or positive. 5. If the father is Rh-positive and the mother is Rh-negative, and the baby inherits the father’s Rh factor, the mother will develop anti-Rh antibodies; this baby will be okay, but any future babies may be attacked by the anti-Rh antibodies if that baby has the Rh-positive trait in its blood. V. Blood Clotting 10
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A. The cardiovascular system is a closed and pressurized system. B. If a break or leak in the system couldn’t be stopped, you would lose a large amount of blood. C. Several substances in blood plug leaks. D. Hemostasis, clotting, is accomplished through a chain of events. 1. When the inner wall of a vessel is damaged, an underlying collagen fiber becomes exposed. 2. Platelets that are floating in the blood begin to attach to that rough, damaged site. 3. The attached platelets release several chemicals that draw more platelets, creating a platelet plug. 4. The platelets secrete serotonin, which causes blood vessels to spasm, decreasing blood flow to that area. 5. Within 15 seconds, blood clotting (coagulation) begins. a. With the help of calcium ions and 11 different plasma proteins, a chain reaction starts. b. One of the clotting proteins, prothrombin, produced by the liver with the help of vitamin K, is converted to thrombin. c. Thrombin transforms fibrinogen, dissolved in the blood, into a solid, hairlike form called fibrin. d. Fibrin forms a netlike patch at the site of the injury, snagging more blood cells and platelets; within 3–6 minutes, a clot is created. e. Once the clot is formed, it begins to retract and pulls the edges of the damaged tissue together, allowing the edges to regenerate the necessary epithelial cells to make a permanent repair; the clot is dissolved over time when it is no longer needed. E. Clotting gone bad 1. The clotting reaction must be stopped, or clotting would continue unchecked. 2. A rough surface on smooth blood vessel allows platelets to begin “sticking,” forming a clot called a thrombus. 3. A thrombus in a coronary artery can partially or totally block blood flow to a portion of the heart, causing a heart attack. 4. Part of the thrombus can break off and travel (called an embolus) until it gets 11
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stopped by a small vessel, partially or completely blocking the vessel and affecting blood flow. 5. A cerebral embolus would cause a stroke; a pulmonary embolus would affect oxygenation. 6. Aspirin, heparin, or Coumadin can be taken to decrease the risk of clot formation; streptokinase is a “clot buster.” VI. Blood Vessels: The Vascular System A. Structure and Function 1. Blood leaves the heart through the aorta, which branches into large vessels called arteries. 2. Arteries divide into smaller and smaller vessels, the smallest of which are called arterioles. 3. Arterioles feed into capillaries that form capillary beds in the body’s tissues, allowing oxygen and nutrients to diffuse into the cells and picking up carbon dioxide and waste products for removal. 4. Blood continues the journey from capillaries to small vessels called venules. 5. Venules combine into veins, which eventually combine into great veins that empty back into the heart. 6. Walls of blood vessels: For most blood vessels, the walls are composed of three layers, often called coats or tunics. a. Tunica interna i. Innermost layer ii. Composed of a loose layer of connective tissue made up of squamous epithelial cells iii. Compacting of the epithelial cells provides a smooth surface so blood can easily pass through. b. Tunica media i. Middle layer ii. Thicker and composed mainly of smooth muscle, elastic tissue, and collagen iii. By contracting or relaxing these muscles, this layer controls the diameter of the vessel to meet certain needs of the body at a given time. 12
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iv. Sympathetic nervous system determines the body’s need and changes diameter of blood vessels. c. Tunica externa i. Outermost layer ii. Composed of mostly fibrous tissue, its job is to provide vessel support and protection. 2. The differences in the structure of the blood vessels vary, depending on their job. a. Arteries versus veins i. Arteries possess much thicker walls than veins because arteries are closer to the heart and have to deal with higher pressures ii. Larger arteries contain complete sheets of elastic tissue, elastic laminae, in their middle walls to help deal with increased pressure. iii. Lumen in veins is larger than in arteries and also contains valves that prevent backward flow of blood. iv. Relaxation and contraction of muscles that surround veins help to “milk” the blood toward the heart. B. The Capillaries 1. Composed of only the tunica interna, with a diameter of only 0.008 mm (slightly larger than the diameter of a single RBC) that allows easy movement of oxygen and nutrients through the wall, while carbon dioxide and wastes can move into the blood. 2. All the body’s cells require a total of approximately 250 mL of oxygen, producing 200 mL of carbon dioxide every minute when the body is at rest. 3. Capillary beds a. Composed of two types of blood vessels: a vascular shunt, which is a main road connecting the arteriole to the venule, and true capillaries, which make the actual exchanges with tissue cells b. True capillaries can be considered the on and off ramps from and to the vascular shunt. c. Precapillary sphincters are composed of smooth muscle and act as tollbooths, either allowing or stopping blood flow as they contract and open. 13
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d. If it is allowed through, it travels to the true capillaries and to cells; otherwise the blood travels through the vascular shunt. C. Regulation of Blood Pressure 1. Measuring blood pressure a. Important diagnostic test, performed with a stethoscope and sphygmomanometer b. Balloonlike cuff is inflated and squeezes the brachial artery shut. c. As cuff deflates, the stethoscope, placed over the brachial artery, allows listener to hear the first sound (systole) of blood flow returning to the artery. d. The last sound (diastole) indicates there is no longer any pressure required for blood to flow through the artery. e. Pressure is measured using a column filled with mercury, a round pressure gauge, or a digital readout. 2. Regulation of blood pressure: Cardiac output: heart rate and times; stroke volume a. Heart rate: beats per minute b. Stroke volume: amount of blood pumped per beat i. Blood volume ii. Force of contraction c. Autonomic nervous system changes heart rate and contractile force. d. Ions, hormones, and body temperature can alter heart rate. e. Age, sex, and exercise can all affect heart rate. 3. Peripheral resistance a. Blood vessel diameter b. Sympathetic innervation to tunica media causes vasoconstriction. c. Smaller diameter = higher pressure. 4. Blood volume a. Fluid volume b. ADH and other hormones VII. The Lymphatic Connection 14
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A. The lymphatic system runs parallel to the CV system and has three major responsibilities: 1. Maintain fluid balance by returning interstitial fluid to the venous side of the CV system. 2. Assist the CV system in distributing nutrients and hormones, and the removal of waste products from tissues. 3. Help to prevent infection and disease by utilizing lymphocytes. VIII. Common Disorders of the Cardiovascular System A. Pump Problems 1. Right-side heart failure (formerly Cor pulmonale) a. An older term for a condition in which the right side of the heart can’t move blood efficiently because of heart muscles working harder than they normally do. b. Muscles on the right side become too large and can no longer pump efficiently. c. Polycythemia (thick blood because of elevated RBC levels) or constricted pulmonary vessels can cause the heart to work harder. d. Occurs in 85% of patients with COPD. 2. Left-side heart failure a. Can affect the left or right side of the heart. b. Pumping action of the heart cannot overcome resistance in the blood vessels, and the increased pressure allows fluid to leak from the vessels and into the tissues. c. In right-sided heart failure, the left pump is working normally, but the right side cannot take all the returning blood, and the blood begins to back up. d. Symptoms may include enlarged liver, spleen, and carotid arteries as well as swelling of the feet, ankles, and/or hands. e. In left-sided heart failure, the right side is pumping normally, but the left side cannot take all the blood being delivered, so blood begins to back up in the lungs. f. Fluid leaks out of the vessels when pressure becomes too high, resulting in pulmonary edema. g. Symptoms can include shortness of breath, wet-sounding cough, and hypoxia. 15
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3. Valve problems a. Two types of valve problems i. Valve is too small (valvular stenosis). ii. Valve is too large, allowing backflow of blood (valvular insufficiency). b. Clots can form in the damaged valve, which can detach and flow through the blood vessels and lead to pulmonary embolus or stroke. c. Papillary muscles attach to the undersides of the cusps of the valve, and damage to these areas allows backflow of blood into the atria when the ventricle contracts. B. Vessel Problems 1. Arteriosclerosis, or hardening of the arteries, occurs to some extent to all of us as we age. a. Results from thickening of the interna. b. Causes involved vessels to become less flexible or even brittle, increasing risk of rupture and likelihood of high blood pressure. 2. Atherosclerosis is a potentially life-threatening condition in which fatty deposits called plaques build up on the inner lining of blood vessels. a. Blood flow can then become greatly or completely blocked by this build-up. b. Plaque is composed of cholesterol. c. Any blood vessel can be susceptible to atherosclerosis, but coronary and cerebral arteries are particularly susceptible. d. Heredity is one factor for atherosclerosis, and it is a common side effect of diabetes. 3. Myodcardial Infarct a. If blood flow is restricted in one or more coronary arteries, heart muscle may become oxygen-starved with the result of dying myocardial tissue. b. Dying myocardial tissue is labelled a myocardial infarction, or heart attack. i. True heart attack occurs when there is an insufficient supply of blood from the coronary artery to the tissues of the heart. ii. Could result from plaque build-up in arteries decreasing flow or a piece of plaque that breaks off and occludes the artery. 16
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iii. A clot that forms and blocks the artery can be another scenario. iv. If the limiting of blood is sufficient to kill heart tissue, the condition is called a myocardial infarction (MI). v. Most MIs start out slowly, with little or no pain (silent MI), and may progress over hours, days, or even weeks. vi. If there is blockage of blood flow to the brain, a cerebral vascular accident (CVA), or stroke, can occur. vii. Reduced blood flow to tissues that leads to tissue injury but not tissue death is called tissue ischemia. c. Symptoms may include chest pain, chest heaviness, and pain in the left shoulder, neck, jaw, or radiating down the left arm. i. Nausea, heartburn, weakness, clamminess, diaphoresis, shortness of breath, and dizziness can also be warning signs. ii. Denial can delay treatment. iii. The first hour is the most important. iv. Call 911 and chew an aspirin immediately because research shows this increases survival rates. d. Blockage of blood flow to the brain can cause a cerebral vascular accident (CVA) or stroke. e. Reduced blood flow leads to tissue injury, called ischemia. 4. Aneurysm a. A localized weakened area of blood vessel wall that may have been caused by a congenital defect, disease, or injury b. Appears to be a familial tendency for abdominal aortic aneurysms. c. Often no symptoms, but when aneurysm continues to expand it can rupture, causing hemorrhage; if it is a major artery, an individual can bleed out in a matter of minutes d. Surgical intervention can remedy the situation if detected early. C. Blood problems 1. Secondary polycythemia: Chronic low levels of oxygen cause the body to produce more erythrocytes to transport more oxygen; primary polycythemia can be caused by bone marrow cancer. 17
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2. Anemia is a condition with fewer RBCs than normal or an abnormal or deficient amount of hemoglobin. a. Common symptoms include pale skin, mucous membranes, and nail beds, fatigue and muscle weakness, shortness of breath, and/or chest pain. b. Sickle cell anemia i. Inherited condition in which RBCs and hemoglobin molecules cannot form properly ii. Resultant RBCs are crescent-or sickle-shaped and tend to rupture. iii. As cells are destroyed, the body is stimulated to produce more RBCs, resulting in immature cells because of the high production rate. iv. Ruptured cells clog up small vessels, and thicker blood from the high number of RBCs leads to increased clotting and impaired ability to carry oxygen. 3. Leukemia, usually because of bone marrow cancer, results in high numbers of white blood cells; the WBCs are immature and ineffective. 4. Leukocytosis is often caused by an infection and also results in a high WBC count. 5. Leukopenia is a low WBC count as the result of drugs or chronic infection. 6. Hemophilia is an inherited blood condition that prevents healthy blood clotting. 7. Thrombocytopenia is a condition in which there are fewer circulating platelets than normal. a. If the count is low enough, even routine acts of moving can lead to bleeding. b. Causes include liver dysfunction, decreased levels of vitamin K, radiation exposure, and bone marrow cancer. CLASSROOM ACTIVITIES 1. Demonstrate rhythm strips reflecting different types of arrhythmias, such as atrial fibrillation, ventricular fibrillation, and sinus bradycardia. Have students discuss what the heart is doing when a particular arrhythmia is present. 2. Assign each student a formed element in the blood. For a big class, also assign a blood type antigen, including the presence of Rh factor. Have each student prepare a report, using visual aids, explaining the purpose of the formed element, where it is produced, and disorders affected by the excessive or diminished quantity of that type of cell. Have the students present their reports to the class. 18
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TEACHING STRATEGIES 1. Help students to trace the flow of blood as well as the flow of the electrical impulse through the heart. Students should learn to associate the electrical impulse visible on the EKG with the various stages of contraction in the heart. 2. Take a blood specimen and, using Wright stain, view it under a microscope. Discuss the components that make it identifiable. FACTOIDS 1. A simple and inexpensive test for elevated WBC counts could be used as a predictor of impending heart attacks in women. Inflammation plays a role in strokes and heart attacks, perhaps by weakening blood vessels and causing atherosclerotic build-up. Another marker of inflammation is the C-reactive protein, but WBC counts are easier and cheaper to perform and are just as accurate a predictor. 2. More than 60 million Americans have some form of cardiovascular disease. It is the leading cause of nonaccidental death in this country. Major risk factors include high blood pressure, high cholesterol, diabetes, obesity and overweight, smoking, inactivity, heredity, age, and male gender. Contributing factors include stress, postmenopausal drops in hormonal levels, and heavy alcohol consumption. It has been shown that people who are overweight and carry most of their weight around their middle are at higher risk for heart attacks than those who carry their weight distributed over their frame. ETHICAL DILEMMAS 1. You’re invited to a friend’s house for Thanksgiving dinner. After dinner, your friend’s father complains of “heartburn,” saying his left arm is tingling and he feels short of breath. You’re pretty sure he’s having a heart attack and recommend he call 911. He says, “No, it will go away in a minute. I just ate too much.” Do you override his wishes and call 911 anyway? What do you do? 2. This friend’s father collapses. As you examine him, you realize he’s not breathing and has no pulse. You have your friend call 911 (if you haven’t called them already). As you prepare to do CPR, your friend tells you that this man is HIV-positive. You don’t have a oneway valve/mask with you and will have to perform mouth-to-mouth directly. Do you perform CPR now, or do you wait for EMS to arrive? ANSWERS TO TEST YOUR KNOWLEDGE Test Your Knowledge 13–1 Answers, p. 258 1. d 2. d 3. d 19
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4. left ventricle 5. right 6. tricuspid Test Your Knowledge 13–2 Answers, p. 264 1. b 2. b 3. c 4. b 5. systole; diastole 6. coronary Test Your Knowledge 13–3 Answers, p. 268 1. a 2. b 3. b 4. albumin 5. mononuclear agranulocytes 6. albumin, fibrinogen Test Your Knowledge 13–4 Answers, p. 272 1. a 2. a 3. b 4. c 5. agglutination 6. vitamin K Test Your Knowledge 13–5 Answers, p. 277 20
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1. c 2. d 3. d 4. a. tunica interna; b. tunica media; c. tunica externa 5. tunica media 6. inotropism ANSWERS TO THE CASE STUDY, P. 282 a. I would suspect the patient is having either a heart attack or angina and is at least in the early stages of COPD. b. The patient needs a complete physical to find out what is going on. Perhaps medication could prevent a more serious heart condition from developing. Most of my suggestions would involve lifestyle changes. He needs to exercise and lose some weight, give up smoking, and eat better. ANSWERS TO REVIEW QUESTIONS, P. 282–283 Multiple Choice 1. c, 2. b, 3. a, 4. b, 5. c, 6. b, 7. c, 8. b Fill in the Blank 1. a. help maintain body’s fluid balance b. assist cardiovascular system in distributing nutrients and oxygen, hormones, and removal of waste products c. help prevent infection and disease 2. ischemia 3. sphincters 4. Vitamin K 5. Septum 6. increase 7. increase 8. red blood cells 21
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Short Answer 1. Blood pressure is controlled by controlling cardiac output, peripheral resistance, and blood volume. Cardiac output, a combination of heart rate and stroke volume, is infl uenced by the autonomic nervous system, by ions, and by temperature. Peripheral r esistance, the resistance to flow in a blood vessel, is controlled by changing blood ve ssel diameter. Smaller diameter causes higher pressure. Sympathetic innervation of the tunica media controls blood vessel diameter. Blood volume is a function of fluid v olume. Fluid volume is generally controlled by hormones, which control urination. 2. Blood flows from the right atrium through the tricuspid valve into the right ventricle; from the right ventricle through the pulmonary valve into the pulmonary arteries; from the pulmonary arteries into the lungs; from the lungs through the pulmonary veins back to the left atrium; from the left atrium through the bicuspid (mitral) valve and into the left ventricle; from the left ventricle through the aortic valve and into the aorta. 3. Type A blood has A antigens and anti-B antibodies, type B blood has B antigens and antiA antibodies, Type O blood has no antigens and both anti-A and anti-B antibodies, and type AB has both A and B antigens and no antibodies. 4. Hemostasis, or the stoppage of bleeding, occurs through a chain of events. When a wound is bleeding, blood loss must be controlled. First the vessels constrict. Then platelets are activated, becoming sticky and forming a water-soluble platelet plug in the wound. These platelets also release serotonin, which causes blood vessels to spasm, thereby decreasing blood flow to that area. After 15 minutes, coagulation (clotting) begins. A chain reaction starts with the help of calcium ions and 11 different plasma proteins (clotting factors). One of the clotting proteins, prothrombin, converts to thrombin, which transforms fibrinogen to fibrin that forms a netlike patch at the injury site. Once the clot is formed, it eventually begins to retract and, as a result, pulls the damaged edges of the blood vessel together. This allows the edges to regenerate the necessary epithelial tissue to make a permanent repair over time. 5. There are three types of formed elements: red blood cells, white blood cells, and platelets. Red blood cells transport oxygen, white blood cells fight infection, and platelets form clots to prevent blood loss. 6. Iron is important in your diet because you need iron to make hemoglobin, the molecule responsible for transporting oxygen in your blood. 7. The direction of the wave of contraction is important because the wave must allow the atria to contract before the ventricles so that the atria can pump blood into the ventricles. The wave also must travel from the apex of the ventricles toward the base of the heart so that blood is pushed up toward the vessels exiting the ventricles, like pushing toothpaste toward the opening of the tube. 8.
A thrombus is a blood clot that forms in the lumen of a blood vessel. A thrombus that 22
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forms in the vascular system of the heart can partially or totally block blood flow to a portion of the heart, resulting in a coronary thrombosis, which can cause a heart attack. An embolus is a thrombus that breaks off and flows through the circulatory system. It becomes a problem when it travels down too narrow a blood vessel and becomes lodged, partially or totally blocking downstream blood flow.
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Name _____________________ CHAPTER 13—WORKSHEET Multiple Choice 1) The tissue that divides the left and the right sides of the heart is called the: A) atrioventricular valve. B) apex. C) septum. D) base. 2) The _____ is considered the pacemaker of the heart. A) sinoatrial node B) atrioventricular node C) Purkinje fiber D) bundle branch 3) Which type of blood vessel carries blood away from the heart? A) Artery B) Vein C) Capillary D) Anastomosis 4) What color would you expect oxygenated blood to be? A) Bright red B) Bluish C) Green D) Purple 5) The tough membrane that surrounds the heart is called the: A) endocardium. B) fibrous pericardium. C) myocardium. 24
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D) visceral pericardium 6) The inner lining of the heart is called the: A) endocardium. B) pericardium. C) myocardium. D) epicardium. 7) Which blood vessel carries blood from the heart to the lungs? A) Aorta B) Vena cava C) Pulmonary artery D) Pulmonary vein Worksheet—p. 1 of 3 8) To which chamber of the heart does the aorta attach? A) Right atrium B) Right ventricle C) Left atrium D) Left ventricle 9) Which blood type has both anti-A and anti-B antibodies? A) Type A B) Type B C) Type AB D) Type O Fill in the Blank 10) The upper chambers of the heart are called _____. 11) _____ is the phase of the cardiac cycle when the heart contracts. 12) A person with type A blood will have anti-_____ antibodies in their plasma. Matching 25
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Please match each term with the appropriate description. 13) _____ Plasma
A.
A red blood cell
14) _____ Erythrocyte
B.
The liquid portion of blood
15) _____ Leukocyte
C.
A platelet
16) _____ Thrombocyte
D.
A white blood cell
Please match each type of cell with the appropriate function. 17) _____ Erythrocyte
A.
Performs phagocytosis.
18) _____ Thrombocyte
B.
Produces antibodies.
19) _____ Neutrophil
C.
Helps with blood clotting.
20) _____ Lymphocyte
D.
Secretes heparin.
21) _____ Eosinophil
E.
Involved in parasitic infections
22) _____ Basophil
F.
Carries oxygen.
Worksheet—p. 2 of 3 Short Answer 23. Please list three substances that the blood transports. 24. Please list two possible causes of anemia.
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Worksheet—p. 3 of 3 ANSWER KEY Chapter 13—Worksheet 1) C 2) A 3) A 4) A 5) B 6) A 7) C 8) D 9) D 10) atria 11) Systole 12) A 13) B 14) A 15) D 16) C 17) F 18) C 19) A 20) B 21) E 22) D 23) Answers will vary, but may include: oxygen, carbon dioxide, nutrients, antibodies, hormones, and waste products. 27
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24) Answers will vary, but may include: iron deficiency, vitamin deficiency, inherited traits (as in sickle cell), bone marrow dysfunction, improper formation of blood cells, and haemorrhage.
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Name ______________________ LABELING ACTIVITY INSTRUCTIONS: Please label the following diagram.
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LABELING ACTIVITY ANSWER KEY
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Chapter 14 THE RESPIRATORY SYSTEM: IT’S A GAS LEARNING OUTCOMES List the basic functions of the respiratory system. Differentiate between respiration and ventilation Name and explain the functions of the structures of the upper and lower respiratory tracts. State the purpose and function of the mucociliary escalator. Discuss the process of gas exchange at the alveolar level. Describe the various skeletal structures related to the respiratory system. Explain the actual process and regulation of ventilation. Discuss several common respiratory system diseases.
MULTIMEDIA FOUND ON THE POWERPOINT LECTURE OUTLINE 1. Gas Exchange in the Lungs Animation (slide 22) 2. Oxygen-Delivery Devices Video (slide 101) 3. Lungs Animation (slide 110) 4. Pulmonary Function Test Video (slide 150) 5. Spirometry Video (slide 151) 6. Oximeters Video (slide 152) 7. Pneumonia Animation (slide 158) 8. COPD Video (slide 161) 9. Asthma Video (slide 165) 10. Asthma Animation (slide 166) 11. Pneumothorax Animation (slide 176) 12. Tuberculosis Video (slide 181) 1
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13. Apnea Video (slide 184) 14. ARDS Animation (slide 186) 15. Allergic Rhinitis Video (slide 187) 16. Airway Burns Animation (slide 188) 17. Perfusionists Video (slide 189) 18. Respiratory Therapy Video (slide 190)
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Lecture Outline I. System Overview A. The respiratory system’s primary function is to transport oxygen from the environment and get it into the bloodstream to be used by cells, tissues, and organs to sustain life. 1. The respiratory system moves 12,000 quarts of air per day into and out of the lungs. 2. The respiratory system also removes waste gas—carbon dioxide—from the body to the environment so it doesn’t build up in the bloodstream. 3. Cellular respiration depends on a continuous supply of oxygen, found in abundance in the air we breathe. 4. Using oxygen produces the by-product carbon dioxide, which would become toxic if allowed to build up in the bloodstream. 5. The respiratory system is closely related to the cardiovascular system, and these two systems are sometimes together called the cardiopulmonary system. 6. Major components of the respiratory system: a. A thoracic cage that houses, protects, and facilitates function for the system b. Upper and lower airways that conduct, or move, gas throughout the system c. Two lungs that serve as the vital organs d. Terminal air sacs called alveoli surrounded by a network of capillaries that allow gas exchange e. Muscles of breathing (diaphragm, and accessory muscles) B. Ventilation versus Respiration 1. The air we breathe is a mixture of gases. a. Nitrogen is predominant; it's an inert gas, which means it leaves the body unchanged. b. Oxygen c. Carbon dioxide d. Argon 2. Ventilation is the bulk movement of air down to the terminal air sacs, or alveoli, of the lungs. 3. Respiration is the process of gas exchange; oxygen is added to the blood, and carbon dioxide is removed. a. External respiration: movement of oxygen from the alveoli to the blood 3
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b. Internal respiration: movement of oxygen from the blood to the cells 4. The respiratory system is responsible for providing all the body’s oxygen needs and removing carbon dioxide. a. System is a series of branching tubules (bronchi, bronchioles) that transport the atmospheric gas deep within our lungs to the alveoli, the terminal end of the respiratory system. (Think broccoli.) b. Each alveolus is surrounded by a network of capillaries. i. Forms alveolar–capillary membrane. ii. Interface between the respiratory and cardiovascular systems II. The Upper Respiratory Tract A. The upper airways begin at the nares, or nostrils, and end at the vocal cords. B. The functions of the upper airways include: 1. Heating or cooling air to body temperature 2. Filtering 3. Humidifying 4. Sense of smell, or olfaction 5. Producing sounds, or phonation 6. Ventilation, or conducting gas to lower airways C. The Nose 1. Opening of respiratory system 2. Rigid structure comprised of cartilage and bone 3. Three main regions within the space behind the nose, called the nasal cavity, including: a. Vestibular region i. Located inside the nostrils ii. Nose hairs, called vibrissae, covered with sebum iii. Sebum helps trap particles and keeps the hairs soft and pliable. b. Olfactory region i. Responsible for the sense of smell ii. Roof of the nasal cavity 4
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c. Respiratory region i. Lined with mucous membranes and richly supplied with blood ii. Air is warmed to body temperature and moistened. iii. Three scroll-like bones, also called conchae or turbinates a. Split incoming air into three channels, providing more surface area. b. Make incoming air current more turbulent, bringing more air in contact with the mucous membranes for warming and humidifying. 4. The nose is responsible for one-half to two-thirds of the total airway resistance in breathing. 5. There would be less resistance and less work if the tube were larger. 6. Therefore, mouth breathing predominates during stress, exercise, or nasal congestion because the oral cavity is larger and creates less resistance. D. Going to Ride the Mucociliary Escalator 1. Airways lined with respiratory mucosa-pseudostratified ciliated columnar epithelium with goblet cells 2. Goblet cells and submucosal glands are interspersed and produce about 100 mL of mucus per day. 3. The mucus resides as two layers. a. A watery layer called the sol layer houses the cilia so they stay flexible and can move the layers. b. The top layer is the gel layer that is more viscous and sticky, trapping small particles. 4. Cilia function a. Cilia act as tiny oars resting in the watery sol layer. b. They propel the gel layer and its trapped debris to be expelled. c. In the nose, the debris is propelled toward the nasal cavity; if located in the lungs, debris is propelled toward the oral cavity to be coughed or swallowed. d. Smoking paralyzes this escalator. E. The Sinuses 1. Air-filled cavities in facial bones 2. Drain into nasal cavity (called paranasal sinuses). 5
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a. Named for specific facial bones in which they are located (ethmoid, sphenoid, maxilla, frontal) 3. These cavities help prolong and intensify sound produced by the voice and help to lighten the weight of the head. 4. Not all sinuses exist at birth, but rather develop as we do, accounting for the change in facial features as we age. 5. Sinuses also help to warm and moisten air. F. The Pharynx 1. Hollow muscular structure lined with epithelial tissue starting posterior to the nasal cavities. 2. Divided into three sections: a. Nasopharynx i. Uppermost section beginning behind nasal cavities ii. Lined with respiratory mucosa; passage for air only iii. Contains lymphatic tissue called the adenoids and passageways into the middle ear called the eustachian tubes (auditory tubes). b. Oropharynx i. Center section of the pharynx located behind the oral, or buccal, cavity ii. Lined with stratified squamous epithelium; food, liquid, and air pass here. iii. Air breathed through the mouth and nose passes through this section. iv. Uvula and soft palate v. During swallowing, the uvula and soft palate move in a posterior and superior position to protect the nasopharynx from the entry of food or liquid. vi. Tonsils a. Part of the lymph system b. Palatine tonsils are located in the oropharynx, as are the lingual tonsils at the back of the tongue. c. Pharyngeal tonsils (adenoids) in nasopharynx c. Laryngopharynx i. Lowermost portion of the pharynx 6
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ii. Opens into both the esophagus (digestive system) and the larynx (respiratory system). G. The Larynx (voice box) 1. Semirigid structure composed of cartilage connected by muscles and ligaments that provide movement of the vocal cords to control speech 2. Thyroid cartilage: The Adam’s apple is the largest of the cartilages found in the larynx. 3. The cricoid cartilage: inferior border, provides structure and support in an exposed area of the airway. 4. Epiglottis a. A leaf-shaped fibrocartilage, flaplike structure over the glottis (opening that leads into the larynx and eventually the lungs); the space between the vocal cords is called the rima glottidis. b. Closes during swallowing to prevent food from entering the lungs; food that is swallowed travels into the esophagus, while air travels into the larynx. c. This is called the glottic or swallowing mechanism and closes the glottis tightly, forcing food and fluid to enter the esophagus. d. When we breathe, air can enter the larynx or the esophagus but prefers the larynx because of pressure differences. 5. Vocal cords a. Act as the dividing line between the upper and lower airways. b. Upper airway ends at the vocal cords. c. Lower airway starts below the vocal cords. IV. The Lower Respiratory Tract A. Trachea and Bronchi 1. The lower respiratory tract resembles an upside-down tree, often called the tracheobronchial tree. 2. From the vocal cords, air enters the trachea, or windpipe, extending to the 6th thoracic vertebrae. 3. C-shaped cartilage is found in the anterior portion of the trachea to provide rigidity and protection for the exposed airway in the neck. 4. The esophagus sits in the opening of the C-shaped cartilage in the posterior part 7
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of the neck, allowing the esophagus to expand when swallowing larger chunks of food. 5. The trachea is the largest bronchus and can be thought of as the trunk of the tree. B. Mainstem bronchi 1. The trachea begins branching, or bifurcating, at the center of the chest into the left and right mainstem bronchi (bronchus is the singular form), sometimes called the primary bronchi. 2. The site of bifurcation is called the carina. 3. The right mainstem branches off at a 20–30-degree angle from the midline of the chest. 4. The left mainstem branches off at a more pronounced 40–60-degree angle. 5. This is important because the lesser angle of the right mainstem branching allows foreign bodies that are accidentally breathed in to more often lodge in the right lung. 6. An endotracheal, or breathing, tube placed too far in may be placed in the right mainstem, and only the right lung will expand, which is why an x-ray must be done following tube placement. C. Branching of the bronchi 1. Bronchi must branch into the five lobular bronchi that correspond to the five lobes of the lung. 2. Each lung lobe is further divided into specific segments, and the next branching of bronchi is called the segmental bronchi. 3. From the trachea to the segmental bronchi, the tissue layer is the same. a. Inner epithelial layer contains the mucociliary escalator. b. Middle layer is the lamina propria layer, which contains smooth muscle, lymph, and nerve tracts. c. Third layer is the protective and supportive cartilaginous layer. 4. The branching becomes more numerous and smaller, extending deep into the lung segment. 5. Cartilaginous rings become more irregular and eventually fade away. 6. Near gas exchange regions, the airways simplify to make it easier for gas molecules to pass through. D. Bronchioles 8
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1. Bronchioles average only 1 mm in diameter. 2. There is no cartilage layer, and the epithelial layer becomes pseudostratified ciliated cuboidal—short, squat cells as opposed to columns. 3. The cilia, goblet cells, and submucosal glands are almost all gone. 4. There is no gas exchange yet. E. Terminal bronchioles 1. Terminal bronchioles (generation 16) have an average diameter of 0.5 mm. 2. There are no goblet cells, cartilage, cilia, or submucosal glands at this point. 3. This is the end of the conducting areas. F. Respiratory bronchioles 1. The next airway beyond the terminal bronchioles; gas exchange can occur here. 2. The epithelial lining is simple cuboidal cells interspersed with pancake-like cells called simple squamous pneumocytes. G. Alveolar duct 1. Alveolar ducts originate from the respiratory bronchioles. 2. Walls of the alveolar ducts are completely made up of squamous cells, arranged in a tubular configuration. 3. These give rise to alveolar sacs. H. Alveoli 1. The alveoli are the terminal air sacs. 2. Surrounded by numerous pulmonary capillaries; together make up the functional unit of the lung known as the alveolar capillary membrane. 3. Adults have 300–600 million alveoli, with a total of 80 m2 surface area for oxygen molecules to diffuse across into the capillaries. 4. Blood from the right heart enters the pulmonary capillaries, high in carbon dioxide and low in oxygen. 5. Conversely, the concentration of carbon dioxide is low in the alveoli, and there is a large amount of oxygen. 6. Gas exchange takes place, and the pulmonary capillary blood increases in oxygen concentration, travels to the left heart to be circulated to the body. I. Alveolar Capillary Membrane 9
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1. Four distinct components a. First layer is liquid surfactant layer that lines the alveoli. i. Surfactant lowers surface tension, preventing the alveoli from collapsing. ii. Lack of surfactant can cause stiff lungs that resist expansion. iii. Surfactant develops late in fetal development, thus premature babies may have inadequate surfactant levels. iv. Artificial surfactant replacement therapy can instill surfactant into the lungs of premature babies to prevent collapse or rupture of alveoli. 2. Second layer is tissue layer or alveolar epithelium. a. Composed of simple squamous cells of two types 3. Third layer is the interstitial space a. Separates the basement membrane of alveolar epithelium from the basement membrane of the capillary endothelium and contains interstitial fluid. b. Space is so small that the membranes of the alveoli and capillary appear fused. c. If too much fluid gets into this space (interstitial edema), it separates, making it harder for gas exchange to occur. 4. The fourth component is the capillary endothelium. 5. Cells include the following: a. Type I cells, thin pancakelike cells, squamous pneumocytes, allowing easy gas molecule movement b. Type II cells, or plump granular pneumocytes, produce surfactant and aid in cellular repair. c. Type III cells, or wandering macrophages, ingest foreign particles as they wander through the alveoli. d. Pores of Kohn are small holes between alveoli to allow movement of macrophages from one alveolus to another. IV. The Housing of the Lungs and Related Structures A. The lungs reside in the thoracic cavity and are separated by a region called the mediastinum, which contains the esophagus, heart, great vessels, and trachea. 1. Breathing in and out causes the lungs to move within the thoracic cavity. 10
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2. To prevent irritation of the lungs moving against the thorax, each lung is wrapped in a sac, or serous membrane, called the visceral pleura. 3. The thoracic cavity and the upper side of the diaphragm are also lined with a similar membrane called the parietal pleura. 4. Between the two pleura is a pleural space (intrapleural space) that contains a slippery liquid called pleural fluid, reducing friction of breathing. B. The Lungs 1. Conical shaped with rounded peaks (apex) extending 1–2 inches above the clavicle 2. The bases of the lungs rest on the right and left hemidiaphragm; the right lung base is a bit higher to accommodate the liver. 3. The medial surface of the lung has a deep, concave cavity that holds the heart, called the cardiac impression, which is deeper on the left. 4. The hilum is the area where the root of each lung is attached, containing the main bronchus, pulmonary artery and vein, nerve tracts, and lymph vessels. 5. The right lung has three lobes—upper, middle, and lower—divided by the horizontal and oblique fissures. 6. The left lung has only one fissure, the oblique fissure, and therefore has only two lobes—upper and lower. 7. The lingula is an area of the left lung that corresponds with the right middle lobe. 8. The left lung has only two lobes because the largest part of the heart is located in the left lung area. a. Lingula: an area of the left lung that corresponds with the right middle lobe I. The right lung is larger, with 66% of gas exchange occurring here. C. The Protective Bony Thorax 1. Bone and cartilaginous frame providing freedom of movement 2. Thoracic cage, sternum, and thoracic vertebrae to which each rib attaches a. Consists of 12 pairs of ribs attached by cartilage to allow for their movement while breathing. b. True ribs are pairs 1 through 7; called vertebrosternal because they connect anteriorly to the sternum and posteriorly to the thoracic vertebrae of the spinal column. c. Pairs 8, 9, and 10 are called the false ribs, or vertebrocostal, because they connect to the costal cartilage of the superior rib and again posterior to the thoracic vertebrae. 11
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d. Rib pairs 11 and 12 are called the floating ribs because they have no anterior attachment.
VI. How We Breathe A. The respiratory control center is the medulla oblongata. B. Inspiration is an active process in which the diaphragm is sent a signal via the phrenic nerve, causing it to contract and flatten and increasing thoracic cavity space. C. The increase in thoracic cavity volume decreases pressure, creating a lower pressure in the lungs than in the atmosphere, and air rushes into the lungs. D. The external intercostal muscles also assist by moving the ribs up and outward to increase total volume in the thoracic cavity. E. Exhalation is a passive act caused by a return of the diaphragm to a resting state, decreasing the space in the thoracic cavity, pushing air out. F. Respiratory rate 1. Carbon dioxide levels in blood normally control respiratory rate. 2. If carbon dioxide levels rise in the blood, it means you are not ventilating, or “blowing off” enough CO2, and your medulla oblongata will send signals to the respiratory muscles to increase the rate and depth of breathing. G. Accessory muscles 1. During increased activity, we need more oxygen and must move more air. 2. Accessory muscles are used to help pull up the rib cage to make an even larger space in the thoracic cavity. 3. Accessory muscles a. Scalene muscles in the neck b. Sternocleidomastoid c. Pectoralis major d. Pectoralis minor muscles H. Assisted exhalation 1. Although exhalation is usually passive, there are times when exhalation may need to be assisted, such as in certain diseases. 2. Accessory muscles of exhalation assist in more forceful and active exhalation by increasing abdominal pressure. 12
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3. The main accessory muscles of exhalation are the abdominal muscles that push up the diaphragm and the back muscles that pull down and compress the thoracic cage. I. Pulmonary Function Testing (PFT) 1. Measures lung function in terms of volumes and capacities. a. Volumes actually measured b. Capacities calculated from volumes 2. Measuring lung volumes a. Patient is instructed to: i. First, breathe normally. ii. Then, take a maximum deep breath followed by a maximum exhalation. iii. Various volumes are recorded while the patient is doing this. b. Lung volumes and capacities i. Tidal volume (VT)—the amount of air that moves into or out of the lungs in a normal breath ii. Functional residual capacity (FRC)—the volume of air remaining in the lungs at the end of a normal expiration iii. Inspiratory reserve volume (IRV)—the amount of air that can be forcefully inhaled after a normal inspiration iv. Expiratory reserve volume (ERV)—the amount of air that can be forcefully exhaled after a normal expiration v. Residual volume—the volume of air remaining in the lungs after a maximum expiration vi. Vital capacity (VC)—the maximum amount of air that can be moved into and out of the respiratory system in a single respiratory cycle C. Measuring flows 1. Important indicator of obstructive diseases 2. Total flows are measured, as are: a. Peak flows b. Flows at various points of the exhalation X. Common Disorders of the Respiratory System 13
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A. Atelectasis 1. Atelectasis is a condition in which the air sacs of the lungs are either partially or totally collapsed. 2. The cause may be a patient who can’t or won’t take deep breaths to fully expand the lungs and keep the passageways open. 3. This can be due to surgery or thoracic cage injury. 4. Deep breathing is essential to the expansion of the airways and to the production of surfactant, which helps keep the small alveolar sacs open between breaths. 5. Patients who can’t cough up secretions are also at risk for atelectasis, and the build-up of secretions can lead to pneumonia within 72 hours. B. Pneumonia 1. Pneumonia is a lung infection that is usually caused by bacteria, virus, or fungi. 2. Pneumonia results in inflammation of the infected area with an accumulation of cell debris and fluid. 3. Some pneumonias actually destroy lung tissue. 4. Severe pneumonia can result in death. C. Chronic obstructive pulmonary disease (COPD) 1. COPD is a general disease resulting in difficulty evacuating air from the lungs, large amount of secretions, and lung damage. 2. COPD refers to one or a combination of the following: a. Emphysema i. An irreversible condition in which the alveolar air sacs are destroyed ii. Damaged alveoli make gas diffusion difficult, if not impossible. iii. The lung itself becomes fragile and can easily rupture, like a worn tire. iv. Escaped air flows through the rupture into the thoracic cavity, further inhibiting gas exchange. v. Most common cause of emphysema is smoking. b. Chronic bronchitis i. A potentially reversible lung disease ii. Disease process includes inflamed airways and large amounts of sputum production. 14
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iii. As inflammation progresses, airways swell, and the inner diameter gets smaller, making air exchange difficult and increasing the work of breathing. iv. This causes increased oxygen use and increased carbon dioxide production. D. Asthma 1. A potentially life-threatening lung condition resulting in constriction of the airways, called bronchospasm 2. Difficult to get air in and even more difficult to get air out of the lungs, called gas trapping, resulting in an inability to get fresh, oxygenated air in; the patient breathes the same air repeatedly. 3. Lower oxygen levels and increased carbon dioxide levels occur in the blood. 4. Inflammatory process causes increased secretions, blocking the airways (mucus plugging) and further reducing the passage of air to the alveoli. 5. It can be reversed and managed with medications such as bronchodilators and steroids. E. Pneumothorax 1. A pneumothorax is a condition in which there is air outside the lungs, in the thoracic cavity. 2. Air can enter the thoracic cavity through a hole in the lung or in the thorax. 3. Causes include stab or gunshot wounds or disease processes that damage the lungs. 4. The air from the external environment fills the space meant for the lungs and prevents lung expansion required for breathing. 5. This can be a life-threatening condition and must be treated immediately with a chest tube, sucking the air from the thoracic cavity like a vacuum. F. Pleural effusion 1. A pleural effusion is the buildup of fluid in the pleural space between the parietal and visceral pleura. 2. The fluid may be pus (empyema), serum from blood (hydrothorax), or blood (hemothorax). 3. Gravity tends to push fluids to the bases of the pleural space and can have the same effect as a pneumothorax, restricting lung expansion. 4. Pleural effusions can be treated with antibiotics or by inserting a needle into the collection of fluid and aspirating it. 15
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G. Tuberculosis 1. Tuberculosis, or TB, is an infectious disease, thriving in high-oxygen areas such as the lung. 2. TB bacteria can lay dormant for years before multiplying. 3. Unchecked, TB can cause massive lung damage. 4. TB is treated with medication, but there is concern about a new form of TB that is resistant to traditional medications. H. Symptoms of lung disease 1. There are many symptoms of lung disease, but the most common include: a. Dyspnea (difficulty breathing) b. Tachypnea (rapid respiratory rate) c. Cyanosis (a blue coloring to lips and nail beds) d. Retractions (use of accessory muscles of breathing) e. Tachycardia (rapid heart rate) f. Polycythemia (increased RBC count) I. Smoking 1. The major, preventable cause of respiratory disease is smoking. 2. The annual number of smoking-related deaths in the United States is equal to a jumbo jet filled with passengers crashing with no survivors every day—450,000 people per year. CLASSROOM ACTIVITIES 1. In pairs, have students count one another’s respiratory rate while sitting in class. Next, have students exercise—jumping jacks, or running a flight of stairs, for example. Have them count one another’s respiratory rate after exercising. Have each pair share the respiratory rates before and after exercise. Why did the rates change, and what was going on in the lungs after exercising? 2. Play round robin. Have all the students stand up. Call on one student at a time to name a respiratory structure, in order, starting with the nose and ending with the alveolar-capillary membrane. Any student who cannot name the next structure must sit down. The last student, or students, standing are the winners. TEACHING STRATEGIES 1. Name various respiratory disorders and ask students to state whether they are respiration 16
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or ventilatory problems. Students must be able to defend their selections. 2. Have students put together the entire picture of the respiratory and cardiovascular systems. Have them trace the movement of oxygen through the respiratory system, into the cardiovascular system, to the tissues where oxygen is dispensed and carbon dioxide is collected, and then trace the path of the carbon dioxide until it is blown off by the respiratory system. FACTOIDS 1. For us to speak, we must first expel air from the lungs using all the structures found in the lower airway. As air moves over the vocal cords, the vocal cords cut the air into a series of rapid puffs (ranging from 32 cycles per second for a low bass to 3,136 cycles per second for a high-pitched sound). Normal speaking range is 98–262 cycles per second. It is these puffs of air that make sound, not the vibration of the vocal cords—much like clapping your hands makes a noise. The columns of air created vibrate at a natural frequency. The shorter the pipe, the higher-pitched the sound; in this case, the pipe is the passage from the larynx to the lips and works on much the same principle as blowing across the top of an open bottle—the shorter the bottle, the higher the pitch. The length of the passage from larynx to lips creates tone of the voice. Finally, to form intelligible sounds, the tongue, lips, and mouth must move to turn the sound into recognizable words. 2. The lungs contain almost 1,500 miles of airways and 300 million alveoli. Every minute, you breathe in 13 pints of air. Humans breathe in air and breathe out carbon dioxide; plants take in carbon dioxide and release oxygen. 3.
The reason people yawn is a mystery. While the long-held belief persists that yawning provides the body with more oxygen, some researchers consider that a misconception. One hypothesis suggests that yawning helps keep the brain at its cool, optimal working temperature of 98.6ºF. This is why a person who is under stress, such as someone about to parachute from a plane, yawns before jumping. The link between yawning and tiredness may also be related to brain temperature, which is usually highest at night. Following this theory, contagious yawning, especially among animals, may be a social function as a way of keeping the entire group alert and functioning at its optimal level in case of predators.
ETHICAL DILEMMA 1. When I worked in the neonatal intensive care unit, we had a baby born to a mother who had been smothered with a pillow by the baby’s father. The mother was brain dead but kept alive long enough to deliver her baby. If the mother’s brain was destroyed by lack of oxygen, what do you think happened to the baby, who also suffered from oxygen deprivation? Should the mother have been kept alive to deliver her baby, or should they both have been allowed to die together? As it turns out, the baby had almost continuous seizures because of brain damage, and it died within 24 hours of birth. 2.
Many states are legalizing marijuana for medicinal use. However, according to the American Lung Association, marijuana smoke contains 33 cancer-causing chemicals and marijuana deposits four times as much tar into the lungs when compared with an equal number of 17
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cigarettes. Should marijuana be legalized? Do the medicinal benefits to patients with chronic or terminal conditions smoking marijuana outweigh its risks? ANSWERS TO TEST YOUR KNOWLEDGE Test Your Knowledge 14–1 Answers, p. 292 1. d 2. a 3. c 4. c 5. d 6. olfaction; phonation
Test Your Knowledge 14–2 Answers, p. 296 1. d 2. d 3. c 4. d 5. b 6. b 7. c Test Your Knowledge 14–3 Answers, p. 301 1. d 2. b 3. a 4. d 5. a 6. a 7. haemoglobin 18
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Test Your Knowledge 14–4 Answers, p. 308 1. b 2. d 3. d 4. d 5. c 6. hemopoiesis or hematopoiesis ANSWERS TO THE CASE STUDY, P. 311 a. This could be an asthma flare-up, given his history, and also pneumonia because he has had a bad cold for several days. b. Medication to bronchodilate (open) the airways and fluids and oxygen for the cyanosis are indicated. If this is a bacterial pneumonia, antibiotics could also be indicated. c. Decrease in heart rate and breathing toward normal, decreased use of accessory muscles, improvement in skin color (less cyanosis), and less or a clearing of secretion production would suggest treatment was working. ANSWERS TO REVIEW QUESTIONS, P. 311–312 Multiple Choice 1. d, 2. b, 3. b, 4. d, 5. c, 6. a 7. a Fill in the Blank 1. bronchioles 2. olfaction; phonation 3. cilia; sol; gel 4. sinuses 5. increase; in Short Answer 1. The inner layer of the bronchus is the epithelial layer (mucociliary escalator or pseudostratified ciliated columnar cells). A middle layer contains smooth muscle, lymph, and nerves. The outer layer is the cartilaginous layer. 2. The blood entering the pulmonary capillaries from the pulmonary arteries is oxygen-poor 19
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and carbon dioxide–rich. The air in the alveoli is oxygen-rich and carbon dioxide–poor. So there is net diffusion of oxygen from the alveoli into the capillaries and carbon dioxide from the capillaries into the alveoli down the concentration gradients for both chemicals. Thus oxygen enters the bloodstream, and carbon dioxide leaves the bloodstream in the lungs. 3. Surfactant is vitally important. It prevents collapse and adhesion of alveoli when air leaves the lungs. Without surfactant, alveoli would quickly become damaged. Surfactant also prevents overexpansion of the alveoli during inspiration. 4. A nerve impulse is sent from the medulla oblongata down the spinal cord to the phrenic nerve to the diaphragm. The diaphragm contracts. When the diaphragm contracts, it flattens, increasing thoracic and lung volume. When the volume increases, the pressure in the lungs decreases to lower than atmospheric pressure. Air flows down the pressure gradient into the lungs. This is the mechanism of inspiration. It is an active process, requiring contraction of the diaphragm. Expiration is a passive process. When the nerve impulse shuts off, the diaphragm contracts, decreasing the volume and increasing the pressure in the lungs. Air is pushed out of the lungs by this increased pressure. 5. The wall of the tracheobronchial tree has three major changes as you move from conducting to respiratory zone. The amount of cartilage decreases, the epithelium changes from respiratory mucosa to cuboidal epithelium to simple squamous epithelium, and the amount of smooth muscle decreases. There is no cartilage or smooth muscle in the respiratory zone. Matching Please match each term with the appropriate description. 1)
_____ Pharynx
A. The airway that extends from the larynx to the bronchi
2)
_____ Larynx
B. The membrane that surrounds the lungs, decreasing the friction of breathing
3)
_____ Epiglottis
C. Very small airways
4)
_____ Trachea
D. The air sacs at the terminal ends of the airways
5)
_____ Bronchi
E.
The throat
6)
_____ Bronchioles
F.
Warms and moistens inhaled air; region that detects smells.
7)
_____ Alveoli
G. The primary muscle of breathing
8)
_____ Turbinates
H. The voice box
9)
_____ Pleura
I.
The large airways that branch off of the trachea
10) _____ Nasal cavity
J.
A flap of cartilage that closes off the airways during 20
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swallowing 11) _____ Diaphragm
K. Three scroll-like bones that split inhaled air into several smaller channels, causing turbulent flow
Multiple Choice 12) This portion of the pharynx connects to the nasal cavity and contains the adenoids: A) Oropharynx B) Nasopharynx C) Laryngopharynx D) Hypopharynx 13) This portion of the pharynx connects to the mouth: A) Oropharynx B) Nasopharynx C) Laryngopharynx D) Hypopharynx 14) This portion of the nasal cavity is responsible for detecting smells: A) Respiratory region B) Olfactory region C) Vestibular region D) Palatine region 15) This portion of the nasal cavity contains coarse hairs that filter out particles: A) Respiratory region B) Olfactory region C) Vestibular region D) Palatine region 16) This process involves moving air in and out of the lungs: A) Respiration B) Ventilation 21
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C) Annihilation D) Gas exchange 17) The process involves exchanging oxygen and carbon dioxide with the bloodstream: A) Respiration B) Ventilation C) Annihilation D) Consumption Fill in the Blank 18) The process where oxygenated blood exchanges gases with the tissues is called _____. 19) The _____ is the point where the trachea bifurcates, forming the bronchi. 20) _____ is a phospholipid that lowers the surface tension of the alveoli, preventing them from collapsing. 21) Normally, breathing rate is determined by the level of _____ in the blood. Short Answer/Essay 22. Explain how the mucociliary escalator helps prevent foreign material from getting into the lungs. __________________________________________________________________________ __________________________________________________________________________ __________________________________________________________________________ 23. Which phase of breathing (inhalation or exhalation) is considered active? Which phase is considered passive? __________________________________________________________________________ __________________________________________________________________________ __________________________________________________________________________ 24. Describe the process of inhalation. (In other words, describe the changes in the body that result in inspiration.) __________________________________________________________________________ __________________________________________________________________________ __________________________________________________________________________ 22
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25. Describe the process of exhalation. (In other words, describe the changes in the body that result in exhalation.) __________________________________________________________________________ __________________________________________________________________________ __________________________________________________________________________ ANSWER KEY Chapter 14—Worksheet 1) E 2) H 3) J 4) A 5) I 6) C 7) D 8) K 9) B 10) F 11) G 12) B 13) A 14) B 15) C 16) B 17) A 18) internal respiration 19) carina 20) Surfactant 21) carbon dioxide 23
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22) Mucus is sticky and traps foreign particles. Then the cilia sweep the mucus out and away from the lungs. 23) Inhalation is active. Exhalation is passive. 24) Inhalation begins when signal is sent through the phrenic nerve, triggering the diaphragm to contract. As the diaphragm contracts, it flattens, increasing the volume of the chest cavity. This causes the pressure to drop inside the chest cavity, and air rushes in. 25) Exhalation begins when the diaphragm relaxes, resuming its resting dome shape. The elastic tissue of the lungs also recoils. Together, these actions make the chest cavity smaller. The pressure inside the chest cavity rises, and air is forced out.
24
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Name _______________________ LABELING ACTIVITY INSTRUCTIONS: Please label the following diagram.
25
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LABELING ACTIVITY ANSWER KEY
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Chapter 15 THE LYMPHATIC AND IMMUNE SYSTEMS: YOUR DEFENSE SYSTEMS LEARNING OUTCOMES List and describe the major components of the lymphatic system and their functions. List and describe the major components of the immune system and their functions. Explain the antigen–antibody relationship. Discuss the different barriers that help prevent infection. Name and describe the functions of the white blood cells responsible for protecting the body from invasion. Describe the chemicals that assist in the immune response. Discuss how inflammatory responses and fevers relate to infection. Compare innate immunity with adaptive immunity. Describe the function of lymphocytes in the immune response. Discuss the ways in which the lymphatic system, innate immunity, and adaptive immunity work together to fight infection. List and describe several common diseases of the immune system.
MULTIMEDIA FOUND ON THE POWERPOINT LECTURE OUTLINE 1. Lymphatic Drainage Massage Video (slide 24) 2. Lymphatic System Animation (slide 31) 3. Proper Handwashing and Gloving Techniques Video (slide 53) 4. Fever Animation (slide 92) 5. Leukemia Video (slide 146) 6. Allergic Rhinitis Video (slide 152) 7. EpiPen Video (slide 153) 1
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8. Anaphylaxis Animation (slide 154) 9. Nuclear Medicine Video (slide 155)
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LECTURE OUTLINE I. The Defense Zone A. The immune and lymphatic systems work to protect the body from pathogens that can produce disease. B. Without these systems, the body cannot survive for long. C. If pathogens try to enter the body, they must first get past the barriers, such as intact skin and the secretions of mucous membranes. D. If the pathogen does get into the body, the body recognizes it as not belonging. E. This stimulates a series of responses to neutralize the pathogen. F. Weapons include special cells and powerful chemicals of the immune and lymph systems. G. Chemicals stimulate inflammatory and cleanup responses. II. The Lymphatic System A. Transport system and barracks of the immune system B. Works closely with the cardiovascular system. C. Four functions 1. Recycling fluids lost from the cardiovascular system 2. Transporting pathogens to the lymph nodes, where they can be destroyed 3. Storage and maturation of some types of white blood cells 4. Absorption of glycerol and fatty acids from food D. Structures of the lymphatic system 1. Lymph capillaries: smallest pipes in system a. Parallel to blood capillaries b. Lymph capillaries form a network between cells of connective tissues. c. Filled with lymphatic fluid, or simply lymph d. Empty into lymphatic vessels. 2. Lymphatic Vessels 3
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a. Similar to veins, have valves to direct flow; located in almost all tissues and organs that have blood vessels. b. Body movement and contraction of smooth muscles propel lymph through the system. c. Large lymphatic vessels empty into lymph nodes. 3. Lymph nodes a. Are small—encapsulated bodies divided into sections. b. Range in size from as small as a pinhead to as large as an olive. c. Many lymph vessels empty into each node. d. Consist of sections of lymphatic tissue containing WBCs known as lymphocytes. e. Lymphatic tissue is surrounded by lymphatic sinuses filled with lymph fluid. f. Filter and destroy pathogens using the WBCs. g. Concentrated in the cervical, axillary, inguinal, pelvic, abdominal, thoracic, and supratrochlear areas; adenoids and tonsils, the spleen, and the thymus also contain lymph tissue. 4. Lymphatic trunks a. Lymphatic vessels exiting lymph nodes empty into one of several lymphatic trunks. b. Named for their location, they include the lumbar, intestinal, intercostal, bronchomediastinal, subclavian, and jugular trunks. c. Empty into one of two collecting ducts. 5. Collecting ducts a. Lumbar, intestinal, and intercostal trunks empty into the thoracic duct, a large duct that runs from the abdomen up through the diaphragm and into the left subclavian vein; more than two-thirds of the lymphatic system drains into this duct. b. Bronchomediastinal, subclavian, and jugular trunks empty into the right lymphatic duct, a smaller duct within the right thorax, which empties into the right subclavian vein. 6. The circulation of lymphatic fluid follows this pattern, beginning and ending in the bloodstream: 4
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a. Blood to tissue b. Tissue to lymphatic capillaries c. Lymphatic capillaries to lymphatic vessels d. Lymphatic vessels to lymph nodes e. Lymph nodes to lymphatic vessels f. Lymphatic vessels to lymphatic trunks g. Lymphatic trunks to collecting ducts h. Collecting ducts to subclavian veins, reentering the bloodstream E. Lymphatic Organs 1. Spleen a. A spongy organ in the upper left quadrant of the abdomen b. Blood sinuses surround islands of white pulp containing lymphocytes and islands of red pulp containing both RBCs and WBCs. c. Spleen functions to remove and destroy old, damaged, or fragile RBCs. d. Also filters pathogens from bloodstream and destroys them. e. Not an essential organ and can be surgically removed; removal in children can severely compromise immunity but has far less effect on adults. 2. Thymus a. Soft organ located between the aortic arch and sternum b. Very large in children because of all the new infections it must handle c. Gets smaller or even disappears in adults as the immune system fully matures in its ability to fight infection. d. Packed with lymphocytes, which mature into a type of WBC called a T lymphocyte e. Also secretes a hormone that stimulates maturation of the T lymphocytes in lymph nodes. 4. Cancer a. Cancer cells spread around the body via the lymphatic system. b. Stages 5
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i. No spread from origin ii. Spread to local tissues iii. Spread to lymph nodes and/or blood iv. Spread to distant organs II. The Immune System A. The immune system provides the weapons and the troops to protect the body from invasion. 1. It consists of cells, chemicals, and barriers that protect against pathogens. 2. Some processes are active, some passive, some inborn, and others change with experience. B. Antigens and Antibodies 1. Antigens a. Cell surface identification molecules b. Each living thing has unique cell surface antigens. c. Self- and non-self-recognition are the heart of how the immune system functions. d. A well-functioning immune system ignores self-antigens and attacks non-self antigens. 2.
Antibodies
a. Proteins that bind to antigens, eventually destroying them b. One of the most potent weapons of the immune system c. Antibodies are called into action when a foreign antigen invades the body. C. Innate versus Adaptive Immunity 1. Innate Immunity a. Front line of defense against invasion b. Body’s inborn ability to fight infection c. Prevents invasion, or if the invasion occurs, it takes steps to prevent the spread of infection. d. Can recognize non-self but cannot specifically identify invaders. 6 .
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e. Collection of crude mechanisms, like weapons of mass destruction, killing pathogens and healthy tissue alike 2. Adaptive (Acquired) Immunity a. Targets specific invaders and spares healthy tissue as much as possible. b. Remembers invaders from previous encounters and prepares for future invasion, improving the response with experience by learning and changing (vaccinations). c. Works together with innate immunity. D. Components of the Immune System 1. Physical barriers exist to act as first-line defense. a. Anything that prevents invaders from getting inside the body prevents infection. b. Physical barriers are located in areas most likely to be invaded. c. Skin and the mucous membranes of the eyes, digestive, respiratory, and reproductive systems d. These surfaces are difficult to penetrate and are packed with WBCs and lymph capillaries to trap invaders. e. Fluids associated with physical barriers, including tears, saliva, urine, mucous secretions, and sweat, contain chemicals that act as barriers. f. Barriers are part of innate immunity. 2. White blood cells (WBCs, leukocytes) a. Responsible for defending against invaders b. Originate in the bone marrow; move to other parts of the body. c. Not released into the bloodstream until they are needed d. Types of WBCs i. Neutrophils a. Phagocytosis b. Born in the bone marrow and are the most common leukocyte in the bloodstream. c. First responders at the site of invasion, cleaning up the area by ingesting pathogens and releasing chemicals that increase tissue damage and inflammation, stimulating immune response 7
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d. Neutrophils are part of innate immunity. ii. Macrophages a. Modified monocytes, a type of agranulocyte, which leave the bloodstream and enter tissues b. Phagocytic, active in the later stages of an infection c. Macrophages release chemicals that stimulate the immune system. d. Display antigens. e. Part of innate immunity; trigger adaptive immunity. f. Part of the mononuclear phagocyte system (or reticuloendothelial system) iii. Basophils and Mast Cells a. Both release chemicals to promote inflammation. b. Basophils are granulocytes that enter infected tissue from the bloodstream. c. Basophil numbers are low unless an active infection is present. d. Mast cells are not mobile and are stationed throughout the body, always found in connective tissue, and when stimulated they release chemicals. e. Basophils and mast cells are part of innate immunity. iv. Eosinophils a. Granulocytes that break down the chemicals released by basophils and mast cells, reducing inflammation b. Numbers are generally low unless an infection or allergy is present. c. Play a part in fighting infection from parasitic worms. d. Eosinophils are part of innate immunity. v. Dendritic cells a. Modified monocytes b. Weakly phagocytic c. Most important role of dendritic cell is as antigen-presenting cell (APC). 8
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i. Ingest foreign cells, placing the foreign antigens into their cell membrane, then cruise the lymph nodes displaying the foreign antigen, looking for lymphocytes that match the antigen. ii. This is an important trigger of adaptive immunity. iii. ADCs are the red flags that alert adaptive immunity to respond. vi. Natural killer (NK) cells i. Part of innate immunity ii. Release chemicals to kill any cells displaying foreign antigens— pathogenic or your own cells. iii. NK cells wipe out any infected cell in the body. vii. T lymphocytes i. Type of adaptive immunity called cell-mediated immunity ii. Cytotoxic T cells kill infected cells and release immune-stimulating chemicals. iii. Helper T cells activate parts of adaptive immunity. iv. Regulatory T cells regulate immune response. v. Memory T cells remember pathogens after exposure. c. B Lymphocytes i. Responsible for the part of adaptive immunity; antibody-mediated immunity ii. Plasma cells produce antibodies to non-self antigens. iii. Memory B cells remember pathogens. 3. Chemicals a. Cytokines i. Proteins produced by damaged tissues and WBCs ii. Stimulate immune response; increasing inflammation, stimulating lymphocytes, and enhancing phagocytosis. iii. Involved in both innate and adaptive immunity b. Interferon 9
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a. A cytokine produced by cells that have been infected by a virus b. Binds to neighboring, uninfected cells and stimulates them to produce chemicals that may protect these cells from viruses. c. Has also had some success as an anticancer drug, but is still experimental. c. Tumor necrosis factor (TNF) i. A cytokine produced by WBCs that stimulates macrophages ii. Causes cell death in cancer cells. iii. New classes of drugs that inhibit TNF have been successful in treating rheumatoid arthritis. d. Interleukins i. Many cytokines are types of molecules called interleukins. ii. At least 10 interleukins are involved in nearly every aspect of innate and adaptive immunity. iii. Have been used with moderate success to treat some forms of cancer. e. Complement cascade i. A complex series of reactions that activates 20 proteins that are usually inactive unless activated by a pathogen invasion ii. Cause lysis of bacterial cell membranes, stimulation of phagocytosis, attraction of WBCs to site of infection, clumping of cells with foreign antigens, and alteration of the structure of viruses. c. Complement cascade is part of both innate and adaptive immunity. 4. Inflammation a. The inflammatory response is a familiar weapon. b. Symptoms include pain, swelling, heat, and redness. c. Deliberate action of the body in response to any tissue damage d. Response helps to wall off the damaged area to prevent further spread and allow the battle to focus at this site—called margination. e. When tissue is damaged, cells release histamine, a cytokine that attracts WBCs to the site, increases the permeability of capillaries, and causes local vasodilation; extra fluid causes swelling. 10
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f. More blood comes to the site, causing heat. g. WBCs destroy pathogens and clean away dead cells. h. Increase in fluid and cells in the area increases pressure and creates pain. i. Inflammation is an innate immune mechanism but plays an important part in adaptive immunity. j. Inflammation is a two-edged sword; too much inflammation, particularly in closed spaces, can cause more tissue damage than the original injury or infection. k. Widespread inflammation, called anaphylaxis, can be fatal. 5. Fever a. Immune system releases cytokines that promote inflammation and immune response. b. One of the cytokine targets in the brain is the hypothalamus, responsible for setting and maintaining body temperature. c. Effect of cytokine is elevated temperature set point, or a fever. d. Rise in body temperature is a deliberate attempt by immune system to destroy pathogens by “baking” them out. III. How the Immune System Works A. Innate Immunity 1. First, the pathogen must get past physical and chemical barriers; most pathogens are kept out. 2. The presence of a foreign antigen is detected by neutrophils, which ingest the foreign antigen, destroying it and releasing chemicals that attract other WBCs to the site of infection, stimulating inflammation. 3. The release of cytokines and stimulation of inflammation attract macrophages and natural killer cells to the infection site. 4. Macrophages phagocytize infected cells, and NK cells use chemicals to destroy infected cells; both cells release chemicals to further stimulate inflammation, activate more immune cells, and trigger the complement cascade. 5. Pathogens are under attack from phagocytosis, noxious chemicals, membrane rupture, clumping, and even alteration of molecular structure. 6. Chemicals signal the hypothalamus to raise body temperature. 7. This is crude warfare, with innate immunity destroying anything non-self without sur11 .
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gical strikes or specific weapons, just a desperate attempt to defeat the invaders. 8. In some cases, this is enough, but often innate immunity is buying time for adaptive immunity. 9. Innate immunity stimulates adaptive immunity. 10. When phagocytic cells ingest pathogens, they display the foreign antigen on their cell membrane, essential to activate B and T cells. IV. Adaptive Immunity A. Adaptive immunity fights pathogens specifically. 1. This part of the system has memory, learns from experience, and recognizes specific pathogens. 2. B and T lymphocytes remember pathogens and mount specific responses to those pathogens if they meet again. 3. Because of adaptive immunity, immunizations are able to prevent illness. 4. Innate and adaptive immunity work hand in hand, each needing the other to function effectively. 5. To function, lymphocytes must be able to recognize pathogens and to ignore the body’s own tissues. B. Lymphocytes must be selected through positive or negative selection. 1. Positive selection a. Lymphocytes that recognize and bind to antigens are allowed to survive. b. Lymphocytes that don’t do this do not survive. 2. Negative selection a. Some lymphocytes recognize and bind to the body’s own antigens and must be destroyed before they can destroy healthy cells. b. Negative selection is the destruction of self-recognizing lymphocytes. 3. Lymphocytes develop, mature, and are selected when you are young; they begin as undifferentiated cells with the potential to become anything. a. During the maturation process, they become differentiated, growing to be specialized cells with a special function. b. Undifferentiated lymphocytes are produced in the bone marrow, and some migrate to the thymus, destined to become T cells. 12
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c. Other lymphocytes develop and mature in the bone marrow to become B cells. d. Lymphocytes, once specialized, wait in the lymph node for a pathogen they recognize. e. They can remain in suspended animation for a long time. C. Lymphocyte activation, wake-up call for lymphocytes 1. When the innate immune system phagocytizes infected cells, the pathogen’s antigens are displayed on the outside of the cell, making them visible to specialized lymphocytes that then become activated and destroy them. 2. This is the beginning of adaptive immunity. D. Lymphocyte proliferation, production of lymphocytes 1. Only a few lymphocytes recognize each pathogen, but hundreds of thousands are needed to attack an infection. 2. There are two types of proliferation. a. Proliferation of helper T cells i. Helper T cells help other lymphocytes, so there must be many of these cells before other lymphocytes are activated. ii. Helper T cells are stimulated to divide by binding to antigen-presenting cells and by stimulation by cytokines. b. Helper T cells continue to divide, then help the proliferation of B cells and other types of T cells. c. AIDS i. Caused by HIV infection of helper T cells ii. Causes a failure of activation and proliferation of both B and T cells. E. B and T Cell Action 1. B cells a. Antigen-displaying cells send out a signal calling for the weapons of adaptive immunity. b. B cells are responsible for humoral or antibody-mediated immunity, fighting pathogens by making and releasing antibodies to attack a specific pathogen. c. B cells develop into plasma cells and memory B cells; antibodies are made by plasma cells and released into the bloodstream. 13
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i. Primary response a. Antibodies bind to antigens of infecting cells, destroying the pathogen by inactivating the antigen, causing clumping of antigens, activating complement cascade, and releasing chemicals to stimulate the immune system and enhance phagocytosis. b. Antibody-mediated mechanisms destroy pathogens and further stimulate both adaptive and innate immunity, continually increasing response to pathogens until they are all destroyed. ii. Secondary response a. Memory B cells are stored in lymph nodes until they are needed. b. Memory cells mount a faster response if exposed to a pathogen seen before. c. Responsible for the immune system’s ability to improve with experience 2. T cells (four types) a. Helper T cells b. Cytotoxic T cells i. Activity of cytotoxic T cells is known as cell-mediated immunity because the cytotoxic T cells are responsible for the death of pathogens or pathogen-infected cells directly. ii. Cytotoxic T cells release a cytokine called perforin, which causes infected cells to develop holes in their membranes and die. iii. Cytotoxic T cells also release other cytokines that stimulate both innate and adaptive immunity, especially attracting macrophages to the site of infection to dispose of cellular debris. iv. Response of cytotoxic T cells is the primary response of cell-mediated immunity. v. Some T cells give rise to memory T cells. c. Regulatory T cells i. Immunity is controlled largely by positive feedback, so something must act to turn off the response when the threat is over. ii. Regulatory T cells are the off switch for the immune system. 14
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iii. Regulatory T cells are not fully understood and were discovered only recently. iv. Evidence suggests they directly inhibit B cells and cytotoxic T cells, releasing cytokines that decrease immune and inflammatory response. v. Malfunction of regulatory T cells is implicated in some types of allergy, asthma, and autoimmune diseases. d. Memory T cells i. Help to recognize the infection upon reexposure. K. Acquiring immunity 1. Natural active immunity: creation of memory cells resulting from actual infection 2. Artificial active immunity: creation of memory cells resulting from vaccination (deliberate exposure to weakened pathogen) 3. Natural passive immunity: immunity transferred across the placenta during fetal development 4. Artificial passive immunity: A patient is injected with antibodies for a pathogen. V. The Big Picture A. An army of pathogens wants to invade your body. B. First, they must get past the body’s barriers. C. If they enter the body, immune cells (neutrophils, macrophages, basophils, etc.) are stimulated and chemicals (cytokines) are released that stimulate inflammation and phagocytosis. D. Macrophages and other cells that have ingested some of the invaders are now wearing foreign antigens, move to the lymphatic system, and search the lymph nodes for T and B cells that will recognize the intruder. E. Helper T cells are activated and cause the proliferation of B cells and cytotoxic T cells, as well as releasing chemicals to further stimulate phagocytosis and inflammation. F. B cells produce antibodies that destroy invaders and further stimulate immune response. G. Cytotoxic T cells destroy invaders directly and release chemicals that further stimulate immune response. H. Immune response, both innate and adaptive, will continue to be stimulated until the feedback loop is stopped, at least in part, by regulatory T cells. 15
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I. Memory B cells and T cells will be stored in lymph nodes for later use if another army of these same types of pathogens invades. J. Macrophages and other phagocytic cells will clean up the debris left by the warfare waged by the immune system, and the body will return to normal. VI. Common Disorders of the Immune System A. Immunodeficiency disorders 1. Patients with any of several different types of immunodeficiency disorders have underactive immune systems. 2. The immune system doesn’t respond properly to invasion and doesn’t protect patients from infection. 3. Minor infections can be fatal; clients get ill very easily and recover slowly. 4. Causes of immunodeficiency can be chemicals, viruses, genetics, radiation exposure, or even medications. 5. Immune-compromised clients include those with AIDS, SCID, leukemia, and some anemias; chemotherapy patients; and those taking immune-suppressing medications after organ transplants. B. Autoimmune disorders 1. Autoimmune disorders are the opposite of immunodeficiency disorders, occurring when the immune system attacks some part of the body. 2. The body fails to ignore self and destroys its own tissues. 3. There are hundreds of different disorders, each affecting a different system. 4. Treatment is frequently with immunosuppressant drugs, but they may not be successful, and side effects can be severe. 5. Examples of autoimmune disorders a. Rheumatoid arthritis (joint linings) b. Multiple sclerosis (myelin sheath in CNS) c. Lupus erythematosus (every tissue, perhaps DNA) d. Type 1 diabetes (beta cells in pancreas) e. Myasthenia gravis (acetylcholine receptors in skeletal muscle) f. Graves’ disease (thyroid gland) 16
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g. Addison’s disease (adrenal gland) C. Allergies 1. Hypersensitivity reactions, or allergies, occur when the immune system mounts an overactive response to a foreign antigen, often treating a harmless antigen like an invading pathogen. 2. Local hypersensitivity reactions, such as hay fever, hives, or rashes, are generally mild and not life-threatening. (Asthma is a local reaction but is more serious.) 3. Systemic hypersensitivity reactions, or anaphylaxis, are life-threatening because mast cells and basophils release immune-stimulating chemicals throughout the body, causing vasodilation and leading to dangerously low blood pressure and heart failure. 4. Hives and asthma may also accompany anaphylactic reactions. CLASSROOM ACTIVITIES 1. Assign each student a part of the immune system. For instance, one person could be a B lymphocyte, one person could be a T lymphocyte, and so on. Select a few students to play the role of a pathogen. Have students act out the events that occur within the immune system when a pathogen attempts to invade. One student could play the skin, trying to keep a pathogen from getting by. When the pathogen manages to get past the barrier, other students could demonstrate attempts to neutralize the pathogen. 2. Have students trace the flow of lymph from the time fluid leaks from the blood vessels until it is returned to the bloodstream. TEACHING STRATEGIES 1. The immune system is so complex, it can be difficult to help students understand how all the components function together. To understand how the system works together, it is vital they first understand each individual component then understand that one component does not function alone; rather, immunity occurs because all the components work to complement one another. 2. Once the lymph and immune systems are understood, revisit the lymph system to help students see how it contributes to the immune system. FACTOIDS 1. The lymphatic system is not a closed system, has no central pump, and functions as a lowpressure system. As a result, lymph fluid circulates very slowly and is somewhat dependent on muscle contraction and gravity to move it through the system. Rhythmic contractions of the lymph vessel walls also help draw fluid into the lymphatic capillaries. 2. Scientists at the Salk Institute have discovered a molecule named “survivin,” which pre17
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sents in a lot of cancer cells. It is believed responsible for turning normal cells into cancer cells without invoking the immune system. It will likely be a focus of future pharmacology because survivin seems to be responsible for allowing cancer cells to survive and multiply. ETHICAL DILEMMAS 1. If a patient with HIV develops cancer of an organ, should the patient receive an organ transplant? Some people believe that organs for transplantation should be reserved for those people with the longest life expectancy; others feel that HIV patients cannot survive the immunosuppression that is required for transplant recipients, while still others feel that organ transplantation should be an option for HIV patients. 2. You are caring for a 29-year-old woman who is diagnosed with Hodgkin’s lymphoma. It is an early-stage diagnosis, and the doctor states the chance of recovery is greater than 90%. The doctor outlines the treatment plan so the client fully understands the procedures and risks. She says she does not wish to undergo treatment and prefers to let God heal her. The doctor explains there is almost a certain prognosis of death if she doesn’t receive treatment. The client says she will take her chances. What are your ethical obligations to this patient? 3.
Organizations in some occupational fields, such as healthcare, can mandate that their employees receive immunizations, while others in other fields do not. Should private employers be legally allowed to require workers to obtain vaccinations? How about government employers? How about schools? Why or why not?
ANSWERS TO TEST YOUR KNOWLEDGE Test Your Knowledge 15–1 Answers, p. 319 1. d 2. d 3. c 4. b 5. b 6. d 7. b Test Your Knowledge 15–2 Answers, p. 320 1. b 2. d 18
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3. c 4. c Test Your Knowledge 15–3 Answers, p. 325 1. d 2. c 3. d 4. d 5. c 6. d Test Your Knowledge 15–4 Answers, p. 330 1. a 2. b 3. c 4. b Test Your Knowledge 15–5 Answers, p. 335 1. c 2. c 3. a 4. c 5. a ANSWERS TO THE CASE STUDY, P. 338 The doctor might initially suspect that John has AIDS because John has a mysterious illness and is a former IV drug user. AIDS is ruled out because John’s T-cell count is normal. However, increased neutrophil, basophil, and eosinophil concentrations suggest an infection or allergy. Given John’s symptoms, the doctor should expect a sinus infection secondary to allergic rhinitis (hay fever). ANSWERS TO REVIEW QUESTIONS, P. 338–339 19
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Multiple Choice 1. d, 2. b, 3. a, 4. b, 5. b, 6. d, 7. b 8. f. release chemicals to promote inflammation __b. cell-mediated immunity __a. antibody-mediated immunity __c. act as antigen-presenting cells __e. participate in allergic reaction/kill parasites __d. releases chemicals to kill infected cells Fill in the Blank 1. adaptive or acquired 2. NK cells 3. helper T cells 4. mast cells 5. Positive 6. allergies (hay fever) Short Answer 1. The regions of the body containing lymph nodes are cervical, axillary, inguinal, pelvic, abdominal, thoracic, and supratrochlear areas. Adenoids and tonsils, the spleen, and the thymus also contain lymph tissue. 2. The circulation of lymphatic fluid follows this pattern: blood to tissue, tissue to lymphatic capillaries, lymphatic capillaries to lymphatic vessels, lymphatic vessels to lymph nodes, lymph nodes to lymphatic vessels, lymphatic vessels to lymphatic trunks, lymphatic trunks to collecting ducts, and collecting ducts to subclavian veins, reentering the bloodstream. Thus, lymph fluid starts in the bloodstream and ends in the bloodstream after being filtered. 3. Neutrophils: Perform phagocytosis, ingest pathogens and cellular debris, and release chemicals that increase tissue damage and inflammation, stimulating immune response. Basophils: Release chemicals to promote inflammation. Eosinophils: Counteract the activities of basophils and mast cells, breaking down the chemicals released by basophils and mast cells, thereby reducing inflammation. Macrophages: phagocytic, active in the later stages of an infection; release chemicals that stimulate the immune system. Dendritic cells: weakly phagocytic, antigen-displaying cells (ADC); ingest foreign cells, placing the foreign antigens into their cell membrane, then cruise the lymph nodes displaying the foreign antigen, looking for lymphocytes that match the antigen. Natural killer cells: Release chemicals to kill any cells displaying foreign antigens, pathogenic or the body’s own. T 20
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lymphocytes: cell-mediated immunity. Cytotoxic T cells: Kill infected cells and release immune-stimulating chemicals. Helper T cells: Activate parts of adaptive immunity. Regulatory T cells: Regulate immune response. Memory T cells: Remember pathogens after exposure. B lymphocytes: antibody-mediated immunity. Plasma cells: Produce antibodies to non-self antigens. Memory B cells: Remember pathogens. 4. Innate immunity is inborn. It cannot recognize specific pathogens or remember pathogens it has encountered before. Adaptive immunity recognizes specific pathogens and remembers pathogens once exposed. The ability to remember specific pathogens allows adaptive immunity to improve with experience. Adaptive immunity mounts a stronger, faster response the second time it meets a pathogen. 5. Anti-inflammatory medications decrease inflammation. Inflammation is an important part of innate immunity, and chemicals released during inflammation stimulate adaptive immunity as well. Without inflammation, then, immune response is decreased. 6. Leukemia and lymphoma often result in large numbers of immature, ineffective white blood cells. These ineffective WBCs crowd out mature WBCs, decreasing immune response. Chemotherapy drugs often target rapidly dividing cells. WBCs are rapidly dividing cells. Thus, some forms of chemotherapy decrease the numbers of WBCs available to fight infection. Multiple Choice 1) The smallest lymphatic vessels are called: A) lymph trunks. B) lymph capillaries. C) lymph ducts. D) microlymphatics. 2) This lymphatic vessel empties directly into the left subclavian vein: A) Thoracic duct B) Right lymphatic duct C) Lymph capillary D) Lymph trunk 3) This is a spongy organ located in the left upper quadrant of the abdomen: A) Thymus B) Tonsils 21
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C) Spleen D) Adenoids 4) This organ gets smaller with age and may even disappear in adults: A) Thymus B) Tonsils C) Spleen D) Adenoids 5) Imagine that you are a drop of lymph moving through the lymphatic system. Which of the following correctly traces your path from the tissues to the bloodstream? A) Thoracic duct, lymph node, lymph capillary, subclavian vein, lymphatic vessel B) Lymph capillary, lymphatic vessel, lymph node, lymphatic vessel, lymph trunk, thoracic duct, subclavian vein C) Lymph trunk, lymph capillary, subclavian vein, lymphatic vessel, lymph node, thoracic duct, subclavian vein D) Lymph capillary, subclavian vein, lymph node, lymphatic vessel, lymph trunk, thoracic duct 6) _____________ are chemicals produced by damaged tissues and WBCs that stimulate the immune response. A) Cytokines B) Antigens C) Adenoids D) Lymphatics 7) Symptoms of _____________ include pain, swelling, redness, and heat. A) HIV B) inflammation C) lymphoma D) leukemia Fill in the Blank 8) _____________ are molecules on the outer surface of a cell that identify it as being “friend 22
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or foe.” 9) _____________ are proteins produced by the body that bind to foreign cells/substances. 10) _____________ immunity is the body’s inborn ability to fight infection. 11) _____________ immunity targets specific invaders and is able to remember them in case of future invasion. 12) The _____________ cascade is a complex series of reactions that activates several different pathogen-fighting proteins in the blood. Matching Please match each of the following organs with the appropriate description. 13)_____ Lymph node
A. Structures in the throat that contain lymphatic tissue
14)_____ Spleen
B. Secrete(s) a hormone that helps T lymphocytes mature.
15)_____ Tonsils
C. Filters pathogens out of lymph.
16)_____ Thymus
D. Remove(s) old, damaged RBCs and filters pathogens from bloodstream.
Match each type of cell with the appropriate function. 17)_____ Neutrophils A. Release chemicals like histamine that promote inflammation. 18)_____ Basophils and mast cells
B. Directly kill infected cells and remember past infections.
19)_____ Macrophages
C. Release antibodies and remember past infections.
20)_____ T lymphocytes
D. Perform phagocytosis early in infection.
21)_____ B lymphocytes
E. Perform phagocytosis later in infection; display foreign antigens to stimulate other cells in the immune system.
Short Answer/Essay 22. List four functions of the lymphatic system. __________________________________________________________________________ __________________________________________________________________________ __________________________________________________________________________ 23. List three chemicals that are types of cytokines. __________________________________________________________________________ 23
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__________________________________________________________________________ __________________________________________________________________________ 24. List three ways the complement cascade is helpful in fighting infection. __________________________________________________________________________ __________________________________________________________________________ __________________________________________________________________________ 25. Describe the four different stages of cancer. __________________________________________________________________________ __________________________________________________________________________ __________________________________________________________________________ ANSWER KEY Chapter 15—Worksheet 1) B 2) A 3) C 4) A 5) B 6) A 7) B 8) Antigens 9) Antibodies 10) Innate 11) Adaptive 12) complement 13) C 14) D 15) A 24
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16) B 17) D 18) A 19) E 20) B 21) C 22) Recycling fluids lost by the cardiovascular system; transporting pathogens to lymph nodes for destruction; storage and maturation of some WBCs; absorption of glycerol and fatty acids from food 23) Interferon, tumor necrosis factor (TNF), interleukins 24) Answer may include: lysis of bacterial membranes; attracting WBCs to the site of infection; stimulating phagocytosis; clumping of cells with foreign antigens; alteration of virus structure. 25) Stage 1—no spread; stage 2—spread to local tissues; stage 3—spread to lymph nodes; stage 4—spread to distant organs
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Name __________________________ LABELING ACTIVITY INSTRUCTIONS: Please label the following diagram.
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LABELING ACTIVITY ANSWER KEY
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Chapter 16 THE GASTROINTESTINAL SYSTEM: FUEL FOR THE TRIP LEARNING OUTCOMES Locate and describe the functions of the main organs of the digestive system. Differentiate between ingestion and digestion and between mechanical and chemical processing of food. Trace the journey of a bolus of food from the mouth to the anus. Discuss the structure of teeth. Identify the layers that make up the walls of the alimentary tract. Describe the various enzymes and chemicals needed for digestion. Locate and describe the function of the accessory organs for digestion. Describe common disorders of the gastrointestinal system. MULTIMEDIA FOUND ON THE POWERPOINT LECTURE OUTLINE 1. Swallowing and Digestion Animation (slide 21) 2. GERD Video (slide 54) 3. Appendicitis Animation (slide 111) 4. Eating Disorders Video (slide 169) 5. Anorexia Nervosa Video (slide 170) 6. Bulimia Video (slide 171) 7. Dieticians Video (slide 172) 8. Dental Assisting and Dental Hygiene Video (slide 173)
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LECTURE OUTLINE I. System Overview A. The digestive tract, often called the alimentary tract or canal, is a muscular tube that contains the organs of digestion. 1. The tube begins with the mouth and ends at the anus. 2. In between these two points are the pharynx, esophagus, stomach, small intestine, and large intestine. 3. Accessory organs of digestion include the teeth, salivary glands, liver, pancreas, and gallbladder. B. Functions of the Gastrointestinal Tract A. Ingestion (Food enters the mouth.) B. Mastication (mechanically grinding food with the teeth and tongue, beginning the process of physically breaking it down) C. Digestion (the chemical act of breaking down food into small molecules) D. Secretion (Acids, buffers, enzymes, and water aid in the breakdown of food.) E. Absorption (Once food is broken down physically and chemically, it can be absorbed through the lining of the digestive tract.) F. Excretion or defecation (elimination of waste products) II. The Oral Cavity A. Mouth and oral cavity 1. Mouth leads to the oral or buccal cavity. 2. Lips, or labia, act as the door to this cavity. 3. Hard and soft palates create the roof. 4. Tongue acts as the floor. a. The tongue is a muscular structure that provides taste stimuli to the brain, determines temperature, manipulates food, and aids in swallowing. b. As the tongue moves food around in the oral cavity, saliva is added to moisten and soften food, while teeth crush the food. c. The tongue pushes the food into a ball-like mass, called a bolus, so it may be swallowed or passed to the pharynx. d. The lingual frenulum, a membrane under the tongue, keeps you from swallow2 .
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ing your tongue and aids in speaking. e. The tongue’s base (area of attachment) and the uvula are barriers to the next part of the system, the pharynx. 5. The uvula aids in swallowing, directing food toward the pharynx, and blocking food from entering your nasal cavity. 6. The cheeks form the walls of the buccal cavity. 7. This area receives, tastes, mechanically breaks down, and begins the process of chemical breakdown of food, adding liquid or saliva. 8. Salivary glands a. Controlled by the autonomic nervous system b. Large parotid salivary gland is found slightly inferior and anterior to each ear; swell when you get mumps. c. Ducts from these glands empty into upper portion of oral cavity. d. Smallest salivary glands, the sublingual salivary glands, are under the tongue. e. Submandibular salivary glands are located along both sides of the inner surface of the mandible, or lower jaw. 9. Saliva a. Salivary glands produce 1–1.5 liters of saliva daily. b. Small amounts of saliva keep the mouth moist, but the idea or presence of food increases production significantly. c. Saliva is 99.4% water and contains antibodies, buffers, ions, waste products, and enzymes. d. Enzymes act as organic catalysts to speed up chemical reactions. e. One enzyme, salivary amylase (ptyalin), speeds chemical activity of carbohydrate breakdown. f. After eating, saliva cleans the oral surfaces, reducing the amount of bacteria that grows in the mouth. 10. Teeth a. A baby’s first teeth are the deciduous teeth, falling out in time. b. First tooth erupts around 6 months of age; lower central incisors grow first; all 20 are in place by 21/2 years. 3
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c. Between 6 and 12 years, deciduous teeth fall out and are replaced by 32 permanent teeth. d. Wisdom teeth appear by age 21. e. Types of teeth i. Incisors, located at the front of the mouth; blade-shaped; used to cut food ii. Canine teeth for holding, tearing, or slashing food; also known as eyeteeth or cuspids; located next to incisors iii. Bicuspids, or premolars; transitional teeth iv. Molars have flattened tops; bicuspid and molars crush and grind food. f. Structure of teeth i. Teeth have a crown, neck, and root. ii. Crown is visible and covered by the hardest biologically manufactured substance, enamel. iii. Neck is the transitional section that leads to the root. iv. Most teeth are made up of dentin, mineralized bonelike substance. v. Next layer is connective tissue, pulp, located in the pulp cavity. vi. Pulp cavity contains blood vessels and nerves providing nutrients and sensation; nerves and blood vessels get to the pulp cavity via the root canal. vii. Root is nestled in a bony socket and is held in place by fibers of the periodontal ligament. viii. Cementum covers dentin of root; helps secure periodontal ligament. ix. Cementum is a soft version of bone. x. Healthy gums, or gingiva, help hold teeth in place. xi. Epithelial cells form a tight seal around the tooth to prevent bacteria from coming into contact with the tooth’s cementum. III. Pharynx A. Three parts to the pharynx 1. Nasopharynx is primarily part of the respiratory system, blocked by the soft palate. 2. Oropharynx is located at the back of the tongue. 4 .
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3. Laryngopharynx is a passageway for food, water, and air. B. The epiglottis covers the trachea to prevent food from entering the lungs, forcing food into the opening for the esophagus. IV. Esophagus A. Esophagus is approximately 10 inches long and is connected to the stomach. B. It extends from the pharynx, through the thoracic cavity, through the diaphragm, connecting to the stomach in the peritoneal cavity. C. Esophagus is a collapsed tube until a bolus of food is swallowed. D. Rhythmic contractions, called peristalsis, push food down the esophagus. E. Esophageal walls are lined with stratified squamous epithelium that secretes mucus to make the walls slippery and resistant to abrasion, temperature extremes, and irritation. F. A muscular ring at the top of the esophagus, called the pharyngoesophageal sphincter, relaxes to open the esophagus so food can enter. 1. The muscles of the esophagus begin rhythmic contractions (peristalsis) that work the food down to the stomach. G. At the entrance to the stomach is the lower esophageal sphincter, or cardiac sphincter, opening the door to the stomach and closing to prevent acidic gastric juices from splashing into the esophagus and causing heartburn. H. The whole process of swallowing food takes about 9 seconds on average; fluid takes less time. V. The Walls of the Alimentary Canal A. Walls of the alimentary canal from the esophagus onward 1. Innermost layer, the mucosa, lines the lumen of the canal. a. Composed mostly of surface epithelium with some connective tissue and a thin, smooth muscle layer surrounding it b. Possesses cells that secrete digestive enzymes to break down food and goblet cells that secrete mucus for lubrication. 2. Submucosa a. Next layer, composed of soft connective tissue b. This layer contains blood vessels, lymph vessels, lymph nodes (called Peyer patches, similar to tonsils), and nerve endings. 5
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3. Muscularis externa a. Composed of two layers of smooth muscle b. Innermost layer of muscle encircles canal; outer layer is longitudinal in nature, so it lies in the direction of the canal. c. Stomach is surrounded by a third layer of oblique smooth muscle. 4. Serosa a. Outermost layer, composed of a single thin layer of flat, serous fluid producing cells supported by connective tissue b. Called the visceral peritoneum in most of the canal c. Fluid secreted keeps outer surface of intestine moist and allows friction-free movement of digestive organs against the abdominopelvic cavity. d. Esophagus differs in that it has only a loose layer of connective tissue called the adventitia. 5. Peritoneum serous membrane in abdominal cavity a. Visceral—covers organs. b. Parietal—lines abdominal cavity. c. Peritoneal cavity—potential space between layers d. Retroperitoneal—organs not covered with visceral peritoneum but in abdominal cavity e. Mesentery—drapes of peritoneum that anchor and protect organs VI. Stomach A. The stomach is located in the left side of the abdominal cavity, under the diaphragm, and is covered completely by the liver. B. It is approximately 10 inches long with a diameter that depends on amount of food ingested. C. It can hold up to 4 liters when filled. D. Rugae, or folds, help the stomach expand and contract. E. The stomach has four functions. 1. Temporary holding area for received food 2. Secretes gastric acids and enzymes that mix with food, performing chemical 6 .
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digestion. 3. Regulates the rate at which partially digested food (a thick, heavy, creamlike liquid called chyme) enters the intestine. 4. Absorbs small amounts of water and substances on a very limited basis. (The stomach does absorb alcohol.) F. It takes about 4 hours for the stomach to empty following a meal. 1. Liquids pass through fairly quickly. 2. Carbohydrates move through quickly. 3. Proteins take more time to pass through. 4. Fats take the longest, usually between 4 and 6 hours. G. The stomach is divided into four regions. 1. Cardiac region surrounds lower esophageal sphincter. 2. Fundus, laterally and slightly superior to the cardiac region, temporarily holds food as it enters the stomach. 3. Body is the midportion of the stomach. 4. The two curved parts of the body are the lesser curvature (concave) and the greater curvature (larger convex curve). 5. Funnel-shaped, terminal end is called the pylorus, where most of the work of the stomach is performed; food passes through the pyloric sphincter into the small intestine. H. The muscular action of the stomach works like a cement mixer, achieved by three layers of muscles: longitudinal, circular, and oblique. 1. Stomach churns food as it mixes with gastric juices excreted by gastric glands in the gastric pits of the columnar epithelial lining of the stomach. 2. Stomach works food toward the pyloric sphincter through peristaltic activity of the muscles. 3. Chemical and physical digestion occur here. I. Gastric juice is comprised of hydrochloric acid (HCl), pepsinogen, and mucus. 1. About 1500 mL are produced daily by gastric glands. 2. Pepsinogen is secreted by the chief cells; HCl is secreted by parietal cells combining to produce pepsin, the chief digestive enzyme. 7
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3. Pepsin breaks down protein; HCl breaks down connective tissue. 4. HCl has a pH of 1.5–2; effective at killing pathogens. 5. Mucous cells generate a thick layer of mucus to shield from effects of stomach acids. 6 Stomach also secretes intrinsic factor, allowing vitamin B12 to be absorbed. 7. Three phases of gastric juice production: a. Cephalic phase: Sensory stimulation (sight or smell of food) stimulates parasympathetic nerves via the medulla oblongata, stimulating release of gastrin; gastrin travels through bloodstream and reaches stomach, stimulating gastric gland activity. b. Gastric phase: Two-thirds of gastric juices secreted as food enters the stomach and distends the walls, signaling the brain to secrete more gastric fluid. c. Intestinal phase: Food enters duodenum, which distends and senses the acidity, causing intestinal hormones to be released and slowing gastric gland secretions; brain is signaled to help the slow down; this lasts until the bolus leaves the duodenum. 8. Stomach activity is controlled by parasympathetic nervous system, particularly the vagus nerve. 9. Vagus nerve stimulation increases motility and secretory rates of gastric glands. 10. Rate of chyme movement is important. a. If chyme moves too quickly, food particles may not be sufficiently mixed with gastric juices, leading to insufficient digestion; unneutralized chyme can cause erosion of the intestinal lining. VI. Small intestine A. Overview 1. Small intestine is located in the central and lower abdominal cavity. 2. It functions as the major organ of digestion because it is where most food is digested. 3. Small intestine is small in diameter, not length. 4. Small intestine is the longest section of the alimentary canal, with an average length of 6–20 feet and a diameter ranging from 4 cm where it connects to the stomach to 2.5 cm where it meets the large intestine. 8
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B. Small intestine function a. Walls of small intestine secrete digestive enzymes, important for final stages of chemical digestion, and two hormones that stimulate the pancreas and gallbladder and control stomach activity. b. Eighty percent of the absorption of usable nutrients occurs when chyme meets the mucosal walls. c. Amino acids, fatty acids, simple sugars, vitamins, and water are all absorbed here. d. Remaining 20% is absorbed in the stomach. e. Residual chyme not utilized in small intestine is sent to the large intestine for removal from the body. C. Three regions of the small intestine 1. Duodenum a. Approximately 25 cm long, located near the head of the pancreas b. Derives name from duo (two) and denum (ten), which equals 12—the number of finger widths long that this organ is (10 inches). c. Duodenal function i. Pyloric valve is important, allowing small portions of chyme to enter the duodenum; small intestine can process only small amounts of food at a time. ii. Pancreas and gallbladder add secretions—bile from the gallbladder and pancreatic juice from the pancreas; cholecystokinin, CCK, secreted by small intestine, stimulates gallbladder activity. iii. Bile emulsifies fat, dispersing it in water. iv. Pancreatic juice contains sodium bicarbonate, which neutralizes the acidic chyme. v. Muscular action occurs in two ways: Segmentation causes the mixing of chyme and digestive juices like a cement mixer; peristalsis moves food toward large intestine. 2. Jejunum is the middle section, approximately 2.5 m long. 3. Terminal end is the ileum, 2 m long; it attaches to the large intestine at the ileocecal valve. 9
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D. Wall of the small intestine 1. Has circular folds called plicae circulares and fingerlike protrusions into the lumen called villi. 2. Villi also have outer layers of columnar epithelial cells that possess microscopic extensions known as microvilli. 3. Villi are tightly packed together, giving a velvety texture and appearance. 4. Purpose of the microvilli, villi, and circular folds is to provide an incredible increase in the surface area of the small intestine to almost the size of a tennis court, increasing the efficiency of the absorption of nutrients. a. Each villus contains a network of capillaries and a lymphatic capillary called a lacteal. b. Intestinal glands are located between villi. c. Capillaries absorb and transport sugars (the result of carbohydrate digestion) and amino acids (the result of protein digestion) to the liver for further processing before being sent throughout the body. d. Glycerol and fatty acids (obtained from fat digestion) are absorbed by the villi and are converted into a lipoprotein, which travels on to the lacteal, where it becomes a white, milky substance called chyle. e. Chyle goes directly into the lymphatic system for distribution throughout the body. E. Digestive enzymes 1. Necessary to complete chemical digestion; produced by exocrine cells 2. Walls of small intestine secrete several digestive enzymes important for the final stages of chemical digestion and two hormones that control the activity of the pancreas, gallbladder, and stomach. a. The pancreas is stimulated to secrete as a result of the hormone secretin that is produced by the small intestine. b. Gallbladder activity is stimulated by the hormone cholecystokinin (CCK), which is also produced by the small intestine. c. Lactase, maltase, and sucrase are needed to digest double sugars, called disaccharides. d. Internal lipase is needed for certain types of fats. 3. Mechanical and chemical irritation of acidic chyme, plus distention of the intes10
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tinal walls, cause localized reflex action that releases the enzymes and the two hormones. VIII. Large Intestine A. Overview 1. Beginning at the junction of the small intestine, the ileocecal orifice, and extending to the anus is the large intestine. 2. Large intestine borders the small intestine. 3. Functions a. Water absorption b. Absorption of vitamins produced by the healthy bacteria in large intestine c. Compaction of waste products for elimination 4. No villi; little nutrient absorption occurs here. 5. Approximately 5 feet long and 2.5 inches in diameter, the large intestine has three main regions. a. Cecum i. Pouch-shaped structure that receives any undigested food and water from the ileum ii. Appendix is attached to the cecum. a. A 3-inch-long, slender, hollow, dead-ended tube lined with lymphatic tissue b. Evidence suggests that because it possesses lymphatic tissue, it somehow fights infection or may replenish the beneficial bacteria in the digestive tract when they are destroyed by disease. c. Blocked or inflamed appendix causes appendicitis and must be treated with either antibiotics or surgical removal. iii. Some water used in digestion and electrolytes are reabsorbed in the cecum and ascending colon; water absorbed in a small amount but is essential to maintaining normal fluid balance. b. Colon i. Four sections of the colon a. Ascending colon travels up the right side to the level of the liver. 11
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b. Transverse colon travels across the abdomen just below the liver and the stomach. c. Descending colon bends downward near the spleen and travels to the left side, becoming the sigmoid colon. d. Sigmoid colon extends to the rectum. ii. Rectum opens to the anal canal that leads to the anus. iii. Anal sphincter opens and closes to allow the passage of solid waste (feces) from the colon to the outside world. 6. Peristalsis a. Continues in large intestine but at a slower rate. b. As these slower intermittent waves move fecal matter toward the rectum, water is removed, turning it from a watery soup to a semisolid mass. c. As rectum fills with feces, a defecation reflex occurs, which causes rectal muscles to contract and the anal sphincter to relax. d. If fecal matter moves through too rapidly, not enough water is removed, and diarrhea occurs. e. If fecal matter remains too long in the large intestine, too much water is removed, and constipation occurs. 7. Bacteria a. Bacteria in the bowel help break down indigestible materials. b. Produce B complex vitamins and most of the vitamin K needed for proper blood clotting. IX. Accessory Organs A. Liver 1. The liver weighs 1.5 kg, is located inferior to the diaphragm, and is the largest glandular organ in the body and the largest organ in the abdominopelvic cavity. 2. This organ performs many functions vital to life. 3. It is divided into a large right lobe and a smaller left lobe; the right lobe has two smaller inferior lobes. 4. It receives about 11/2 quarts of blood every minute from the hepatic portal vein (carrying blood full of the end-products of digestion) and hepatic artery (providing oxygen-rich blood). 12 .
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5. Functions of the liver a. Detoxifies the body of harmful substances such as certain drugs and alcohols. b. Creates body heat. c. Destroys old blood cells and recycles their usable parts while eliminating unneeded parts such as the pigment bilirubin, eliminated in bile, and giving feces its distinctive color. d. Forms blood plasma proteins, such as albumin and globulin. e. Produces the clotting proteins fibrinogen and prothrombin. f. Creates the anticoagulant heparin. g. Manufactures bile, needed for the digestion of fats. h. Stores and modifies fats for more efficient use by the body’s cells. i. Synthesizes urea, a by-product of protein metabolism, so it can be eliminated by the body. j. Stores the simple sugar, glucose, as glycogen; when the blood sugar level falls below normal, the liver reconverts glycogen to glucose and releases enough of it into the bloodstream to bring blood sugar levels back to an acceptable concentration. k. Stores ions and vitamins A, B12, D, E, and K. l. Makes cholesterol. 6. Bile a. Secretion of the hormone secretin stimulates bile production, a critical liver digestive function. b. Salts found in bile act like a detergent, breaking fat up into tiny droplets, called emulsification, making the work of digestive enzymes easier. c. Bile helps absorb fat from the small intestine and transports bilirubin and excess cholesterol to the intestine for elimination. d. Bile leaves the liver via the hepatic duct, travels through the cystic duct to the gallbladder, and is stored there until needed by the small intestine. B. Gallbladder 1. The gallbladder is a sac-shaped organ, 3–4 inches long, located under the liver’s right lobe. 13
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2. While storing bile, it absorbs much of its water content, making bile 6–10 times more concentrated; if overconcentrated, bile salts may solidify, forming gallstones. 3. Fatty foods in the duodenum cause the release of CCK. 4. This release causes the smooth muscle walls of the gallbladder to contract, squeezing bile into the cystic duct, through the common bile duct, and into the duodenum. C. Pancreas 1. The pancreas plays a role in digestion and is an endocrine gland. 2. The pancreas is 6–9 inches long, located posterior to the stomach, extending laterally from the duodenum to the spleen. 3. Exocrine portion secretes buffers and digestive enzymes through the pancreatic duct to the duodenum. 4. Buffers are needed to neutralize the acidity of the chyme, with a pH ranging from 7.5 to 8.8, saving the intestinal walls from damage. 5. Secretory action is activated by the release of hormones from the duodenum. 6. Digestive enzymes of the pancreas: a. Carbohydrase: Works on sugars and starches. b. Lipase: Works on lipids. c. Proteinase: Breaks down proteins. d. Nuclease: Breaks down nucleic acids. X. Common Disorders of the Digestive System A. Symptoms of digestive disorders usually include some or all of the following: 1. Vomiting a. Vomiting is a protective mechanism that rids the digestive tract of an irritant or overload of food that stimulates sensory fibers, sending a signal to the vomiting center in the brain. b. Motor impulses are sent to the diaphragm and abdominal muscles to contract, squeezing the stomach muscles and cardiac sphincter at the esophageal opening, and contents are regurgitated. 2. Diarrhea a. Results when the fluid contents in the small intestine are rushed through the 14
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large intestine without reabsorbing enough water. b. Rapid movement reduces nutrient and electrolyte absorption and can cause serious problems. 3. Constipation a. Opposite of diarrhea b. Feces pass too slowly through the colon, and too much water is absorbed. c. Stool becomes hard, dry, and difficult to pass. d. Constipation does not refer to the frequency of defecation but to the hard consistency of the stool. 4. Abdominal pain B. Peptic ulcer disease (PUD) 1. Peptic ulcer disease can affect the lining of the esophagus, stomach, or duodenum. 2. Most common region is the upper part of the small intestine, or duodenum. 3. Caused by an imbalance in the juices of the stomach that produce more acid than normal and erode the mucosal lining of the digestive tract 4. Helicobacter pylori is a bacterium implicated in many ulcers; it causes an open wound in the stomach lining, which is exacerbated by exposure to digestive juices and stomach acids. C. See Table 16-3 on pages 363–364 for additional diseases. CLASSROOM ACTIVITIES 1. Call on students to describe the sequential components of the GI tract. The first student will discuss the teeth, the next will discuss the tongue, the next will discuss the cheeks or saliva, and so on. 2. Assign each student to do a written or oral presentation on an anatomical component of the digestive tract (esophagus, small intestine, etc.) or a physiological component (peristalsis, gastric secretions, etc.). TEACHING STRATEGIES 1. Help students understand the functions of the digestive tract by making each part “come alive” through active descriptions of the various components. This will make the anatomy and physiology of the GI tract more memorable. 15
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2. Use anatomical models or diagrams to demonstrate the various components of the GI tract. Whenever possible, discuss pathophysiology in relation to the various components. 3. Discuss the problems associated with obesity. Introduce MyPlate and talk about the requirements for a healthy diet. FACTOIDS 1. When diagnosing cholecystitis, doctors know to look for the 4Fs: female, fat, forty, and fair-skinned. Overweight white women in their 40s are the most likely group to develop gallbladder problems. 2. The surgical procedure known as stomach stapling can be accomplished in several different ways. One procedure involves placing a “lap band” around the stomach to slow the emptying of the stomach; the client feels full for longer periods than prior to surgery, and appetite is reduced. In another procedure, the surgeon removes a small section of the stomach and bypasses a large part of the bowel to reduce the number of calories absorbed and minimize the size of the stomach, so the client feels full longer. These are just two of the different procedures that can be performed. 3.
More than one-third of U.S. adults, or 78.6 million, are obese. The highest prevalence of obesity in the United States occurs in the South (30.2%), followed by the Midwest (30.1%), the Northeast (26.5%), and the West (24.9%). Visit the Centers for Disease Control and Prevention (CDC) website to see maps and other obesity statistics.
ETHICAL DILEMMAS 1. A variety of disease processes involving the GI tract require removal of large parts of the bowel. This results in malabsorption syndromes. Clients with malabsorption syndrome require the administration of IV nutrients, such as hyperalimentation and interlipids, to keep them alive. However, a serious side effect of these concentrated IV nutrients is often liver damage. Should these clients be given IV nutrients, or should they be allowed to die from the disease that required the removal of the bowel? What is the ethical requirement for discussing these surgeries with the client prior to removal of the bowel? 2. Obesity has become a serious problem for many Americans. With the rise in obesity and the focus our society places on appearance, a lot of Americans are choosing to undergo stomach-stapling procedures. What requirements are we ethically expected to enforce prior to agreeing to perform these types of surgeries? Should there be an age limit on who can have this surgery, or is it permissible to perform surgery on young children? What age limit would be appropriate? ANSWERS TO TEST YOUR KNOWLEDGE Test Your Knowledge 16–1 Answers, p. 346 1. c 16
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2. a 3. b 4. d 5. crown; neck; root Test Your Knowledge 16–2 Answers, p. 352 1. c 2. b 3. c 4. c 5. parasympathetic/autonomic Test Your Knowledge 16–3 Answers, p. 357 1. b 2. c 3. d 4. a 5. c Test Your Knowledge 16–4 Answers, p. 360 1. b 2. c 3. b 4. d 5. b ANSWERS TO THE CASE STUDY, P. 365 a. No. Symptoms of heart attack for males often include centrally located chest pain, chest heaviness, or vague discomfort; pain in the left shoulder or shoulder blade, neck, and jaw (where it mimics a toothache), radiating down the left arm; nausea, heartburn, weakness, or a clammy, sweaty feeling, shortness of breath and/or dizziness. b. heartburn (acid reflux) 17
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c. digestion or control of acid d. The opening from the stomach to the esophagus is on the right, so lying on the right side would promote reflux, making it worse. e. He should not eat so much; make sure he eats earlier in the evening and lies on his back with his head elevated. ANSWERS TO REVIEW QUESTIONS, P. 366–367 Multiple Choice 1. c; 2. a; 3. C; 4. a; 5. d
Fill in the Blank 1. Segmentation; peristalsis 2. appendix 3. pancreas 4. Emulsification 5. constipation Short Answer 1. Chyme is partially digested acidic food that moves from the stomach into the small intestine. Chyle is lipoprotein absorbed into the lymph system in the lacteals of the small intestine. 2. The bacteria in the large intestine help digest undigestible material and produce B vitamins and vitamin K. If these bacteria escape the alimentary canal, they cause serious infections. 3. The liver performs many roles in the digestive process. Because all the nutrients from digestion end up in the liver, the liver is involved in lipid, protein, and carbohydrate metabolism, making and storing molecules. The liver also produces bile, which is necessary for digestion of fats in the small intestine. 4. You can live without a gallbladder. Many people have their gallbladders removed because of gallstones and live for years afterward. The gallbladder is only a storage organ for bile. The liver actually makes bile and will continue to do so even after the gallbladder is removed. 5. There are four basic tissue types in the canal. The innermost layer is the mucosa, the next layer is the submucosa, the third layer is the muscularis externa, and the outermost layer is the serosa. The esophagus differs in that it contains only a loose layer of connective tissues 18
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called the adventitia. Each part of the digestive system has differences in the anatomy of the mucosa depending on the function. The stomach has an extra layer of muscles. Some organs are also retroperitoneal and are not surrounded by serosa.
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Name _____________________ CHAPTER 16—WORKSHEET Multiple Choice 1) The gastrointestinal tract is also known as the _____ canal. A) accessory B) alimentary C) anoesophageal D) absorptodigestive 2) Which of the following is an enzyme found in the saliva? A) Peptidase B) Lipase C) Amylase D) Lactase 3) Teeth are made of a bonelike substance called: A) cartilage. B) dentin. C) duodenum. D) ostium. 4) The innermost layer of the GI tract wall is called the: A) mucosa. B) submucosa. C) muscularis externa. D) serosa. 5) The funnel-shaped end of the stomach that connects to the duodenum is called the: A) fundus. B) body. C) pylorus. 20
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D) cardiac region. Fill in the Blank 6) The _____ glands include the parotid, sublingual, and submandibular glands. 7) A baby’s first teeth are called _____ teeth. 8) The muscular “door” between the esophagus and stomach is called the_____. 9) The_____ is a serous membrane in the abdominopelvic cavity. Multiple Choice 10) Which of the following is not a portion of the small intestines? A) Duodenum B) Jejunum C) Ileum D) Cecum 11) Infection with _____ is a risk factor for developing peptic ulcers. A) Salmonella B) H. pylori C) E. coli D) Gonorrhea 12) The _____ are protrusions into the lumen in the small intestine that create an increased surface area for nutrient absorption. A) villi B) rugae C) sphincters D) uvula 13) Reflux esophagitis is a disease characterized by: A) gastric acid washing backward up into the esophagus. B) malabsorption of wheat gluten. C) autoimmune attack on the bowel. 21
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D) the formation of stones in the gallbladder. 14) Inflammation of the gums is called: A) gingivitis. B) cholecystitis. C) ulcerative colitis. D) gastroenteritis. Matching Please match each structure with the appropriate function. 15) _____ Oral cavity
A. Begins mechanical breakdown of food through mastication.
16) _____ Esophagus
B. The valve that prevents stomach contents from washing back up into the esophagus
17) _____ Stomach
C. Prevents food from entering the trachea during swallowing.
18) _____ Small intestine
D. Produces sodium bicarbonate (which neutralizes acid) and several digestive enzymes.
19) _____ Large intestine
E. Produces hydrochloric acid and pepsinogen to begin digestion of food.
20) _____ Liver
F. Produces bile, detoxifies the body, forms plasma proteins, stores nutrients, makes cholesterol.
21) _____ Gallbladder
G. Opens and closes to control the passage of feces to the outside world.
22) _____ Pancreas
H. Carries food from the throat to the stomach.
23) _____ LES
I. Where the majority of digestion and absorption take place
24) _____ Anus
J. Stores bile.
25) _____ Epiglottis
K. Absorbs water from fecal matter before defecation.
ANSWER KEY Chapter 16—Worksheet 1) B 2) C 22
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3) B 4) A 5) C 6) salivary 7) deciduous 8) lower esophageal sphincter (cardiac sphincter) 9) peritoneum 10) D 11) B 12) A 13) A 14) A 15) A 16) H 17) E 18) I 19) K 20) F 21) J 22) D 23) B 24) G 25) C
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Name LABELING ACTIVITY INSTRUCTIONS: Please label the following diagram.
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LABELING ACTIVITY ANSWER KEY
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Chapter 17 THE URINARY SYSTEM: FILTRATION AND FLUID BALANCE LEARNING OUTCOMES Present an overview of the organs and functions of the urinary system. Describe the external and internal anatomy and physiology of the kidneys. Discuss the microscopic anatomy of the kidney and the importance of renal blood flow. Describe the process of urine formation. Trace the pathway of tubular reabsorption or secretion of electrolytes and other chemicals. List and discuss the importance of hormones for proper kidney function. Describe the anatomy and physiology of the bladder and the process of urine removal from the body. Discuss several common disorders of the urinary system. MULTIMEDIA FOUND ON THE POWERPOINT LECTURE OUTLINE 1. Urinary System Animation (slide 17) 2. Renal Blood Flow Animation (slide 33) 3. Hypovolemic Shock Animation (slide 51) 4. Blood Loss and Blood Pressure Regulation Animation (slide 58) 5. Renin–Angiotension System Animation (slide 59) 6. Urinalysis Video (slide 62) 7. Renal Failure Video (slide 116) 8. Kidney Stones Video (slide 127) 9. Ultrasound Video (slide 128)
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Lecture Outline I. Introduction A. Purification plant, cleaning the blood of waste materials B. Controls electrolyte and fluid balances. C. The kidneys filter blood, reabsorb and secrete ions, and produce urine. D. Without these important functions, death occurs within a few days. II. System Overview A. Anatomical 1. Two kidneys: bean-shaped organs located in the superior dorsal abdominal cavity that filter blood and make urine 2. Ureter: tube that carries urine from each kidney to the urinary bladder 3. Urinary bladder: expandable sac that holds urine; located in the inferior ventral pelvic cavity 4. Urethra: tube that transports urine from the bladder to the outside of the body B. Physiological 1. The job of the urinary system is to make urine, thus controlling the body’s fluid and electrolyte balance and eliminating waste products. 2. Three processes in urine production: a. Filtration b. Reabsorption c. Secretion III. Kidney A. External Anatomy 1. Renal capsule: fibrous layer of connective tissue covering 2. Renal hilum: indentation that gives the kidney its bean shape a. Renal arteries bring blood. b. Renal veins take the filtered blood away. c. The ureter is also attached at the hilum. 2
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B. Internal Anatomy 1. The kidney can be divided into three layers: a. Renal cortex, outer layer i. Grainy in appearance and has little obvious structure to the naked eye. ii. Where blood filtration occurs b. Renal medulla, middle layer i. Contains a number of triangular, striped areas called renal pyramids. ii. Renal pyramids are composed of collecting tubules for the urine that is formed in the kidney. iii. Adjacent pyramids are separated by narrow renal columns—extensions of cortical tissue. c. Renal pelvis, inner layer i. A funnel, divided into two or three large collecting cups called major calyces ii. Each major calyx is divided into several minor calyces, forming cup-shaped areas around the tips of the renal pyramids to collect the urine that continually drains through the pyramids. iii. Kidney is essentially a combination of a filtration and collection system. iv. Blood is filtered by millions of tiny filters in the cortex, and the filtrate flows through tiny tubules in the medulla and collects in renal pelvis. v. Renal pelvis is essentially an enlarged proximal portion of the ureter that empties into the ureter tube, where urine is carried to the bladder. 2. Blood Vessels a. Good blood supply to the kidney is essential for proper function. b. A network of blood vessels traverses kidney tissue. c. A single renal artery enters each kidney at the hilum, branching into five segmental arteries. d. Segmental arteries branch into lobar arteries. e. Lobar arteries branch into interlobar arteries, which pass through the renal columns. f. Arcuate arteries originate from the interlobar arteries and arch around the pyramids in the renal medulla. 3
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g. Cortical radiate (interlobular) arteries branch off arcuate arteries and give rise to afferent arterioles. h. Afferent and efferent arterioles i. Each afferent arteriole leads to a ball of capillaries called a glomerulus. ii. Efferent arterioles leave from the glomerulus and travel to a specialized series of capillaries called the peritubular capillaries and vasa recta. iii. Peritubular capillaries wrap around the tubules of the nephron. i. Blood flow out of the kidney i. From each set of peritubular capillaries, blood flows out from the cortical radiate veins. ii. From there, the blood flows out from a series of veins that are the direct reverse of the arteries with the exception that there are no segmental veins. iii. The blood finally leaves the kidney via the renal vein. C. Microscopic Anatomy of the Kidney: The Nephron 1. The functional unit of the kidney; consisting of millions of microscopic filters and tubules 2. The nephron can be divided into two distinct parts: a. The renal corpuscle, a filter i. Blood enters the renal corpuscle via the glomerulus, a ball of capillaries. ii. Surrounding the glomerulus is a double-layered membrane called the glomerular capsule, or Bowman’s capsule. iii. Layers of the glomerular capsule are similar to layers of a serous membrane. Visceral layer: Inner layer surrounds the glomerular capillaries and is made of specialized squamous epithelial cells called podocytes; combined with the capillary walls, this makes for a very efficient filter. Parietal layer: outer layer, simple squamous epithelium, and completes the container of the filter. iv. Blood flows into the glomerulus and everything but blood cells and a few large molecules, mainly proteins, are pushed from the capillaries across the filter and into the glomerular capsule. v. Material filtered from the blood into the glomerular capsule is called glomerular filtrate. vi. If blood or protein leaks into urine, it can indicate a kidney filtration problem. 4
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b. The renal tubule i. The rest of the nephron is a series of tubes known as renal tubules. ii. Glomerular filtrate travels from the glomerular capsule into the first part of the renal tubule, the proximal tubule. iii. Wall of the proximal tubule is made of cuboidal epithelium with microvilli. iv. From the proximal tubule, glomerular filtrate flows into the nephron loop (or the loop of Henle). v. Nephron loop consists of the descending loop (similar in structure to the proximal tubule) and the ascending loop (simple cuboidal epithelium). vi. Glomerular filtrate travels from the nephron loop to the distal tubule. vii. Wall of the distal tubule is like that of the ascending branch of the nephron loop. viii. From the distal tubule, glomerular filtrate flows into one of several collecting ducts, made of cuboidal epithelium. ix. Collecting ducts lead to minor calyces, then to major calyces, the renal pelvis, and the ureter. x. At this point, the glomerular filtrate is urine. D. Renal blood vessels associated with the nephron 1. Blood vessels are in close proximity to the nephrons because certain substances within the filtrate must be brought back into the bloodstream. 2. Blood approaches the nephron via the afferent arteriole. 3. Blood flows from the afferent arteriole into the glomerulus. 4. Blood flows from the glomerulus via the efferent arteriole into the peritubular capillaries and vasa recta, a series of blood vessels surrounding the renal tubule. 5. These surrounding blood vessels allow for reabsorption back into the bloodstream from the filtrate that is within the tubular system. 6. Blood leaves the nephron via the cortical radiate veins. IV. Urine Formation A. The kidney controls fluid and electrolyte balance by controlling urine volume and composition. B. To form urine, the nephron must perform three processes: 1. Glomerular filtration 5
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a. Fluid and molecules are filtered from the glomerular capillaries into the glomerular capsule. b. The filtrate flows into the renal tubule. c. Moves fluid and chemicals into the nephron from blood. 2. Tubular reabsorption and tubular secretion a. Reabsorption: Substances pass from the renal tubule into the peritubular capillaries and return to the bloodstream. b. Secretion: Substances pass through the peritubular capillaries into the renal tubule and leave the body as urine. c. Control the concentration of chemicals and volume of urine. C. Glomerular filtrate is chemically similar to blood, whereas urine is chemically different. D. Some substances, like glucose, are completely reabsorbed, whereas substances like metabolic waste products (urea and creatinine) are almost completely secreted in urine. E. Control of Filtration 1. The podocytes and capillary walls of the renal corpuscle create a filter with fixed openings. 2. Plasma and many of the substances dissolved in plasma pass through the filter. 3. Blood cells, platelets, and large molecules can’t get through filter, remaining in the bloodstream. F. Filtration rate—higher pressure on one side of the filter than on the other allows chemicals to be pushed though the filter. 1. Autoregulation keeps filtration rate constant over minor changes in blood pressure. 2. Autoregulation can be overridden. a. Because the kidney regulates fluid volume, it works with the cardiovascular system to regulate blood pressure. b. Glomerular filtration can decrease to conserve fluid when blood pressure falls or increase if blood pressure rises. c. Sympathetic nervous system can control urine production through the adrenal medulla, and the secretion of epinephrine or norepinephrine, by vasoconstriction of the afferent arteriole, decreasing glomerular filtration; thus, urine output decreases during fight-or-flight responses. G. Control of Tubular Reabsorption and Secretion 6
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1. Tubular reabsorption and secretion control the chemistry and volume of urine. 2. Tubular reabsorption and secretion are affected by tubule permeability. a. Each section of the tubule can reabsorb and secrete different substances. b. Molecules move across membranes through several different methods. c. Results in dramatic differences in which molecules are reabsorbed or secreted in each part of the tubule. 3. Tubular reabsorption and secretion uses countercurrent circulation. a. Ions move across cell membranes from higher to lower areas of concentration. b. Countercurrent circulation in the nephron is possible because of the concentration gradient, with low ion concentration at the beginning of the descending loop and high concentration at the tip of the loop, as well as the differences in permeability between the descending loop (water) and ascending loop (ions). c. Filtrate flows into the descending loop, reabsorbing water and increasing the concentration of ions; as the filtrate enters the ascending loop, fluid is concentrated because of water loss, the membrane is permeable only to ions, and ions move across the membrane. 4. Reabsorption and secretion are also affected by several hormones that regulate blood pressure. a. Antidiuretic hormone (ADH) i. Made by the hypothalamus ii. Secreted from the posterior pituitary when BP decreases or ionic concentration increases iii. ADH increases permeability of distal tubules and the collecting duct. iv. More water is reabsorbed. v. Less urine is produced. vi. Blood volume increases, osmotic concentration decreases, and blood pressure rises. vii. Alcohol and caffeine inhibit ADH production, increasing urine production. b. Aldosterone i. An adrenocorticosteroid secreted by the adrenal cortex ii. Secreted when plasma sodium decreases or plasma potassium increases iii. Increases the reabsorption of sodium ions and secretion of potassium ions— 7
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increasing serum sodium levels, decreasing serum potassium levels—by the distal tubule and ascending limb of the nephron loop. iv. As sodium is reabsorbed, water is also reabsorbed, decreasing urine volume. c. Atrial natriuretic hormone (ANH) i. Secreted by the atria of the heart when blood volume increases ii. Decreases sodium reabsorption and thus increases urination. d. Renin–angiotensin–aldosterone i. Series of chemical reactions that regulate blood pressure ii. Decrease in blood flow to the kidney causes a special group of cells near the glomerulus, the juxtaglomerular apparatus, to secrete renin into the bloodstream. iii. Renin converts angiotensinogen (made by liver) into angiotensin I. iv. Another enzyme made by the lungs, angiotensin-converting enzyme (ACE), converts angiotensin I to angiotensin II. v. Increases thirst, increases ADH secretion, increases aldosterone secretion, and causes vasoconstriction. vi. Blood pressure is increased by higher fluid volume. vii. Kidneys, lungs, and liver work together to regulate blood pressure. V. The Urinary Bladder and Urination Reflex A. Glomerular filtrate flows out the collecting duct, into the minor calyces, and then into the major calyces forming the pelvis. B. Once in pelvis, the filtrate is urine; no further change in chemistry. C. Urine collects in the renal pelvis and flows down the ureters to the urinary bladder, where it is stored. D. Urinary Bladder 1. Small, hollow organ posterior to the pubic symphysis and retroperitoneal 2. Lined with transitional epithelium, the only epithelium stretchy enough to expand as the bladder fills 3. The ability to stretch is enhanced by a series of pleats called rugae. 4. The bladder has a muscular wall consisting of several layers of circular and longitudinal smooth muscles covered by connective tissue and parietal peritoneum. 8
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E. Urination reflex 1. As urine accumulates, the bladder fills and stretches. 2. This stretch triggers the urinary reflex and the need to void to empty the bladder. 3. Urination was thought to be a spinal reflex, but new research indicates it is controlled by the brain. 4. When the bladder is full, signals are sent from the bladder to the spinal cord to the pons that send parasympathetic signals down the spinal cord, causing contraction of the muscular walls of the bladder, and the bladder empties. F. Urination 1. Urine leaves the bladder via the urethra, a thin, muscular tube lined with several different types of epithelium along its length. 2. Part of the brain can inhibit urination by controlling the internal urethral sphincter, a valve at the junction of the bladder and the urethra, and the external urethral sphincter, a valve that is part of the muscles of the pelvic floor. 3. Sympathetic stimulation of these sphincters prevents urine from leaving the body. 4. Although you have little control over bladder contraction, you have good control over the sphincters starting from age 2 (slightly later in boys). VI. Common Disorders of the Urinary System A. Analgesic nephropathy 1. Overuse or abuse of drugs can severely affect renal function because the kidney excretes most medications after the liver breaks them down. 2. Analgesic nephropathy is caused by long-term use of pain relievers, particularly nonsteroidal anti-inflammatory drugs (NSAIDs) like ibuprofen or naproxen, and especially if combined with caffeine, codeine, or acetaminophen. 3. OTCs can cause chronic kidney damage, leading to kidney failure. B. Chronic renal failure (CRF) 1. CRF is an ongoing, progressive disease of the kidney. 2. Progression may be controlled by treating the underlying cause of the damage or controlling BP and cholesterol. 3. CRF can lead to end-stage renal failure, the final stage of renal failure. 4. Treatment is dialysis or transplantation. C. Diabetes insipidus 9
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1. Diabetes insipidus (DI) is an endocrine disorder characterized by too little ADH or insensitivity of the kidney to ADH. 2. The result is copious amounts of urine being produced, dehydration, and rising sodium levels as the body tries unsuccessfully to conserve water; if not treated, it can be fatal. 3. The opposite of this disorder is water intoxication: Clients have uncontrollable thirst and drink so much water they create dangerously low sodium because of the volume of water diluting it; can lead to brain damage or death. D. Diabetic nephropathy 1. Diabetes mellitus (DM) is characterized by high glucose levels from inadequate, or lack of, insulin. 2. The high glucose levels disrupt the osmotic balance of blood. 3. The kidneys work hard to remove excess glucose, and urine output is high. 4. Over time, the kidney is damaged, known as diabetic nephropathy, beginning with a thickening of the filter surface of the glomerular capsule, eventually leading to breakdown of kidney tissue, destroying the filtering ability. 5. Substances that would normally not pass through, like protein and blood, begin to appear in urine. 6. Kidney function deteriorates. 7. Diabetics can prevent the onset of kidney damage by controlling their blood sugar levels, preventing high blood pressure, and reducing blood cholesterol levels. 8. This is the leading cause of kidney disease in the United States. E. Glomerulonephritis 1. Glomerulonephritis is inflammation of the glomerulus. 2. Glomerulosclerosis is scarring of the glomerulus. 3. Both cause damage to the delicate filter apparatus. 4. When the filter is damaged, blood cells and blood proteins enter the filtrate and eventually appear in urine. 5. Removal of waste products is decreased, and electrolyte balance is usually abnormal because of the change in urine chemistry. 6. There are many causes, including bacterial infection, diabetic nephropathy, systemic lupus erythematous (SLE), and genetic disorders such as Alport syndrome and Goodpasture’s syndrome. 10
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F. Urinary tract infection (UTI) 1. UTI is caused by the movement of fecal bacteria into the urinary tract. 2. Symptoms may include frequent, painful urination; bloody or cloudy urine with an unusual odor; and low abdominal/pelvic pain caused by bladder spasm. 3. Treatment should begin promptly to avoid kidney damage from infection traveling from the bladder to the kidney. 4. UTIs are more common in women because their urethra is shorter. 5. Drinking plenty of water may help. 6. Once diagnosed, UTI is treated with antibiotics and increased fluid intake. G. Kidney stones 1. Kidney stones result when substances in the urine crystallize in the renal tubule, often because the concentration of the molecule is higher than normal. 2. The cause of stones is frequently a mystery. 3. Stones can result from excess calcium or uric acid, or from kidney infections. 4. Some people are more susceptible than others. 5. Some stones pass unnoticed; larger or irregularly shaped stones may lodge in the tubule, obstructing flow and irritating nearby tissues. 6. Symptoms include blood in the urine and severe flank pain. 7. Stones may move on their own or may be treated with increased fluid intake, lithotripsy (shock waves to break the stone), or surgery. 8. Clients are asked to filter their urine to look for the passage of stones, some as small as sand. H. Polycystic kidney disease (PKD) 1. PKD is a genetic disorder. 2. Large cysts form in the kidneys. 3. One form of PKD is so serious that patients die in infancy. 4. The more common form is an adult-onset disorder characterized by decreasing kidney function as normal nephrons are destroyed by cysts. 5. As more cysts develop, the kidneys get very large—one is recorded to have weighed 22 pounds. 11
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6. There is no cure except kidney transplant. I. Hemolytic uremic syndrome 1. Hemolytic uremic syndrome is a disorder caused by an infection with the bacteria E. coli, typically from eating undercooked meat. 2. The bacterium infects the digestive tract and releases toxins, which destroy RBCs. 3. The damaged RBCs lodge in blood vessels in the kidney, blocking them and preventing blood flow to the nephron. 4. Without treatment, permanent kidney damage may result. 5. An incorrect blood transfusion of the wrong type of blood can have much the same effect. CLASSROOM ACTIVITIES 1. Using models and diagrams, have students trace the progress of urine creation, starting with blood entering the kidney and finishing with the urination reflex and micturition. 2. Assign each student a portion of the kidney and have the student create a presentation for the class. Encourage the use of visual aids. TEACHING STRATEGIES 1. Explaining the anatomy and physiology of the urinary system can be challenging. Describe the anatomy first, and then start with introductory physiology, gradually increasing the complexity of the introduction as students grasp each concept. 2. If you have access to a microscope and urine dip sticks, have students collect their own urine specimens. Take a small amount of urine and spin it in the centrifuge. Remove the cells that fall to the bottom of the test tube and examine them under the microscope. Next, using the remaining urine, dip the urine to test for blood or other abnormal components. Finally, have students examine the specific gravity of urine and discuss what makes urine more or less concentrated. FACTOIDS 1. Every parent faces the challenges of potty-training their children. One mistake parents can make that complicates the process is beginning the training too young. Children do not gain control of their urinary sphincter until they reach the age of 2. Boys develop control later than do girls, and it is not uncommon for boys to wet the bed until the age of 7 or 8. 2. Urinary incontinence is a common problem for middle-aged women, especially those who have delivered several children vaginally. The process of pushing the baby out can weaken the vaginal wall, causing prolapse of the bladder into the vagina and weakening the bladder muscle. Incontinence is commonly seen as stress incontinence, with leakage when the woman coughs, laughs forcefully, or sneezes. 12
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3. Some ancient Romans used urine to clean and whiten their teeth. The ammonia in urine helped remove stains. 4. Parauresis, or shy bladder syndrome, is a social anxiety disorder that prevents sufferers from urinating in the presence of others. According to the International Parauresis Association, about 21 million Americans suffer from this condition. ETHICAL DILEMMAS 1. There are many stories of kidneys and other organs being sold on the black market. A donor may claim to be voluntarily donating a kidney when in fact the donor has been compensated by the recipient. Sometimes a “broker” becomes involved, locating people who are willing to donate an organ in return for cash payment. In such cases, the broker usually pays the donor only a small fraction of the total fee. Why is this considered unethical behavior? 2. Should wealthy people be given available organs ahead of average people? Why or why not? ANSWERS TO TEST YOUR KNOWLEDGE Test Your Knowledge 17–1 Answers, p. 375 1. b 2. d 3. b 4. c 5. c Test Your Knowledge 17–2 Answers, p. 380 1. a 2. b 3. a 4. d 5. b Test Your Knowledge 17–3 Answers, p. 385 1. c 2. a 3. b 13
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4. c 5. b ANSWERS TO THE CASE STUDY, P. 387 Jane’s diagnosis is overactive bladder. The other possibilities can be ruled out for the following reasons: No glucose rules out diabetes; no bacteria, blood, or leukocytes rules out urinary tract infection. The results of students' research on suggested lifestyle changes for Jane will vary, but may include training techniques aimed at re-establishing normal voiding intervals and continence, such as bladder training and pelvic floor muscle (PFM) exercises. Other suggestions might include avoiding dietary bladder irritants (e.g., alcohol, caffeine, tomatoes, citrus), moderating fluid intake, improving mobility, and increasing fiber intake. ANSWERS TO REVIEW QUESTIONS, P. 388–389 Multiple Choice 1. b, 2. d, 3. d, 4. b, 5. c, 6. a, 7. b, 8. b Fill in the Blank 1. proximal tubule 2. nephron loop 3. atrial natriuretic peptide 4. pons 5. aldosterone 6. renal pelvis Short Answer 6.There are several regulators of kidney function: Autoregulation keeps filtration relatively constant even as blood pressure changes, protecting the filter from moment-to-moment changes in blood pressure. The sympathetic nervous system controls filtration by release of epinephrine and norepinephrine from the renal medulla. Increased sympathetic response causes constriction of the afferent arteriole, decreasing glomerular filtration. Antidiuretic hormone (ADH) is made by the hypothalamus and secreted from the posterior pituitary when BP decreases or ionic concentration increases. ADH increases permeability of distal tubules and the collecting duct, causing more water to be 14 .
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reabsorbed and increasing blood pressure. Aldosterone increases the reabsorption of sodium ions and secretion of potassium ions by the distal tubule and ascending limb of the nephron loop in response to decreased blood sodium. Urine volume also decreases. Atrial natriuretic hormone is secreted by the atria of the heart when blood volume increases. ANH causes increased urination and decreased sodium reabsorption. The renin–angiotensin–aldosterone system kicks in when blood flow to the kidney decreases. The kidney secretes renin. Renin converts angiotensinogen (from the liver) into angiotensin I. Angiotensin I is converted to angiotensin II by angiotensin-converting enzymes in the lungs. Angiotensin II causes vasoconstriction, increased thirst, ADH secretion, and aldosterone secretion. All these mechanisms increase blood pressure. 2. The three processes necessary for urine formation are filtration, reabsorption, and secretion. Filtration is the movement of substances from plasma into the renal corpuscle. Most substances, except cells and large molecules, are filtered from blood. Reabsorption is the movement of substances from the renal tubules into the blood vessels surrounding the nephron. Substances that are reabsorbed are retained by the body. Tubular secretion is the movement of substances into the renal tubule from the bloodstream. Substances that are secreted leave the body in urine. 3. The bladder is lined with transitional epithelium with rugae. It has a muscular wall consisting of several layers of circular and longitudinal smooth muscle and is covered by connective tissue and parietal peritoneum. 4. Urination is controlled by neurons in the pons. As the bladder fills, stretch receptors signal neurons in the pons, which cause increased contraction of the smooth muscle in the bladder walls. This portion of urination is involuntary. Actual urination is controlled by sympathetic control of a pair of sphincters. You have some voluntary control of the sphincters. 5. A single renal artery enters each kidney at the hilum, branching into five segmental arteries that branch into lobar arteries, which branch into interlobar arteries, which pass through the renal columns. Arcuate arteries branch from the interlobar arteries and arch around the pyramids in the renal medulla. Cortical radiate (interlobular) arteries branch off arcuate arteries and give rise to afferent arterioles. Each afferent arteriole leads to a ball of capillaries called a glomerulus. Efferent arterioles leave from the glomerulus and travel to a specialized series of capillaries called the peritubular capillaries and vasa recta. From each set of peritubular capillaries, blood flows out the cortical radiate veins. From there, the blood flows out from a series of veins that are the direct reverse of the arteries with the exception that there are no segmental veins. The blood finally leaves the kidney via the renal vein. 6. Most kidney disorders are characterized by too much or too little urine production or abnormalities in urine chemistry. Damage to the filtering apparatus, from diabetic nephropathy or glomeronephritis, causes blood and proteins to show up in the urine. Diabetes mellitus and insipidus both cause increase in urine volume. In DM, it’s because the body is making more urine trying to get rid of excess glucose. In DI, it’s because of the body’s inability to control output because of ADH abnormalities. Disorders that cause damage to the filter will cause chemistry 15
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changes. Disorders that damage the tubule or the kidney in general will cause changes in volume. In end-stage renal disease, urine output may cease altogether as kidneys fail to function at all.
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Name _______________ CHAPTER 17—WORKSHEET Matching Match each structure with the appropriate description: 1) _____ Kidney 2) _____ Ureters 3) _____ Urethra 4) _____ Bladder 5) _____ Nephron 6) _____ Glomerulus 7) _____ Bowman’s capsule 8) _____ Hilum 9) _____ Renal pelvis 10) _____ Renal medulla 11) _____ Renal cortex A. The place where urine is stored until urination B. The “notch” in each kidney where the renal artery, renal vein, and ureter attach C. A “ball of capillaries” within each nephron D. The bean-shaped organs that produce urine E. Funnels urine from the kidney into the ureter. F. The tubes that connect the kidneys to the bladder G. The microscopic kidney structure that filters the blood H. Collects fluid filtered through glomerulus. I. The middle layer of the kidney J. The outer layer of the kidney K. The tube that drains the bladder Multiple Choice 17
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12) Fluid passing from the glomerulus into the glomerular capsule is undergoing: A) filtration. B) reabsorption. C) secretion. D) anticipation. 13) Fluid normally found inside the glomerular capsule is called: A) blood. B) plasma. C) urine. D) filtrate. 14) When substances are removed from renal tubules and returned to the blood stream, this is called: A) filtration. B) reabsorption. C) secretion. D) precipitation. 15) This hormone is secreted by the hypothalamus when blood pressure decreases or ionic concentration increases; it results in increased reabsorption of water in the nephron: A) Aldosterone B) Atrial natriuretic hormone C) Antidiuretic hormone D) Adrenaline 16) This hormone is secreted by the adrenal cortex and affects sodium and potassium processing by the nephron: A) Aldosterone B) Atrial natriuretic hormone C) Antidiuretic hormone D) Adrenaline 17) Tubular reabsorption and secretion is dependent on a special type of circulation around the neph18
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ron loop called _____ circulation. A) osmotic B) countercurrent C) active D) reverse 18) The descending nephron loop is permeable to: A) water. B) ions. C) proteins. D) sugar. 19) The ascending nephron loop is permeable to: A) water. B) ions. C) proteins. D) sugar. 20) The process of urine formation involves: A) glomerular filtration. B) tubular reabsorption. C) tubular secretion. D) all of the above. 21) In producing urine, the kidney is able to: A) control the body’s fluid and electrolyte balance. B) eliminate waste products. C) control blood pressure. D) All of the above 22) The _____ bring blood directly to the glomerulus. A) afferent arterioles 19
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B) efferent arterioles C) lobar arteries D) peritubular capillaries Fill in the Blank 23) The _____ –angiotensin–aldosterone system helps to regulate blood pressure. 24) The nephron loop is also known as the loop of _____. 25) The process of _____ ensures that minor changes in blood pressure do not affect the kidneys’ filtration rate.
ANSWER KEY Chapter 17—Worksheet 1) D 2) F 3) K 4) A 5) G 6) C 7) H 8) B 9) E 10) I 11) J 12) A 13) D 14) B 15) C 16) A 17) B 20
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18) A 19) B 20) D 21) D 22) A 23) renin 24) Henle 25) autoregulation
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Name _______________ LABELING ACTIVITY INSTRUCTIONS: Please label the following diagram.
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LABELING ACTIVITY ANSWER KEY
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Chapter 18 THE REPRODUCTIVE SYSTEM: REPLACEMENT AND REPAIR
LEARNING OUTCOMES Differentiate mitosis from meiosis and the role of each in the human life cycle. Locate and describe the functions of the female reproductive organs. Locate and describe the functions of the female reproductive organs. Discuss female reproductive physiology, including the phases of the menstrual cycle, oogenesis, follicle development, and ovulation. Discuss the effects of hormonal control on the female reproductive system. Locate and describe the functions of the male reproductive organs. Discuss male reproductive physiology, including spermatogenesis. Discuss the effects of hormonal control on the male reproductive system. Describe pregnancy and the stages of labor and delivery. Explain common disorders of the female and male reproductive systems.
MULTIMEDIA FOUND ON THE POWERPOINT LECTURE OUTLINE 1. Down Syndrome Video (slide 31) 2. Fertilization of the Sperm and Egg Video (slide 35) 3. Oogenesis Animation (slide 99) 4. Female Reproductive System Animation (slide 100) 5. Spermatogenesis Animation (slide 143) 6. Male Reproductive System Animation (slide 135) 7. Fetal Lie Video (slide 171) 8. First Stage of Labor Video (slide 172) 1
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9. Transition Stage of Labor Video (slide 173) 10. Second Stage of Labor Video (slide 174) 11. Vacuum Extractions Video (slide 175) 12. Infant APGAR Scoring Video (slide 176) 13. Infant Delivery Video (slide 177) 14. Infant Delivery by C-section Video (slide 178) 15. Placenta Video (slide 179) 16. Postpartum Assessment Video (slide 180) 17. Vasectomy Video (slide 184) 18. PMS Video (slide 186) 19. Pre-eclampsia Video (slide 192) 20. Breast Cancer Video (slide 197) 21. Erectile Dysfunction Video (slide 199) 22. Nurse Midwives Video (slide 203)
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LECTURE OUTLINE I. Introduction A. Cells and tissues may be damaged or may simply wear out. B. Asexual reproduction or mitosis: process by which cells make exact copies of themselves C. Sexual reproduction: reproduction that produces new individuals D. Without this ability, the human species would die out, and the journey for the human race would end. II. Tissue Growth and Replacement A. Mitosis 1. Cellular reproduction is the process of making a new cell. a.
Also called cell division, because one cell divides into two cells when it reproduces.
b.
Cells can only come from other cells.
c. Asexual reproduction: Cells make identical copies of themselves without the involvement of another cell. d. Most cells can reproduce themselves, whether they are animal, plant, or bacterial cells. 2. Eukaryotic Cells a. The cells that make up the human body b. Have a nucleus, cellular organelles, and usually several chromosomes in the nucleus. c. Genetic material of the cell is DNA, bundled into “packages” of chromatin known as chromosomes. d. Because chromosomes carry all the instructions for the cells, all cells must have a complete set after reproduction. e. These instructions include how the cell is to function within the body and blueprints for reproduction. f. Some cells, like plants cells, have one chromosome, whereas humans have 46 chromosomes. B. Mitosis in the Body 1. Eukaryotic cells must go through a complicated process to reproduce. 2. Human cells must duplicate all 46 chromosomes, make sure each cell gets all the chromosomes, and duplicate all of the organelles. 3
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3. Mitosis: the process of sorting chromosomes so that each new cell gets the right number of copies of all genetic material 4. Only way eukaryotic cells can reproduce asexually 5. Mitosis, asexual cellular reproduction, serves many purposes: a. Cell replacement: both routine and repair b. Growth: bone, muscle mass, and organ II. Sexual Reproduction A. Reduction Division: Meiosis 1. Offspring are not identical to parents. 2. Involves the union of a cell from one organism with a cell from another organism of the same species to form a unique new organism. 3. In animals, females produce eggs, males produce sperm, and these special cells are gametes. a. Gametes are produced by meiosis, also called reduction division because the daughter cells produced at the end of meiosis have half as many chromosomes as the original. b. The daughter cell fuses with the gamete from another organism, which also has half as many chromosomes, forming a cell that has the total number of chromosomes needed. 4. In humans, the total number of chromosomes needed is 46. a. The 46 chromosomes are paired, so there are 23 pairs of chromosomes. b. Each pair consists of one from the father and one from the mother. c. Chromosomes are matched according to size, shape, and the genes they carry. d. The chromosome pairs are numbered. e. The 23rd pair is the sex chromosome, so named because it determines the sex of the baby. i. XX is female. ii. XY is male. iii. The father determines the sex of the baby because the mother can only contribute X chromosomes. 5. Down syndrome a. Common birth defect that causes short stature, heart defects, increased risk of leu4
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kemia, Alzheimer’s disease, and mental retardation b. Caused by the presence of an extra chromosome 21 in a patient’s cells c. Sometime during meiosis, usually in the mother, chromosomes fail to separate, leaving some daughter cells without a chromosome 21 and others with two chromosomes 21. d. If the egg with the extra chromosome is fertilized, the resulting fetus will have three chromosomes 21 instead of two. e. The probability of a baby with Down syndrome increases in women over 35, although new research shows that men over 50 are also at increased risk for the birth of a child with Down syndrome. III. The Human Life Cycle A. Mitosis and meiosis are absolutely necessary parts of the human life cycle, needed for cell replacement, repair, and production of new organisms. B. Eggs and sperm, with only half as many chromosomes as other cells, are produced by meiosis in specialized organs known as gonads (testes and ovaries). C. Fertilization: During sexual reproduction, the gametes unite and combine their genetic material. D. The fertilized egg, a zygote, has 46 chromosomes. E. The zygote reproduces millions of times via mitosis and develops within the female to change from an embryo to a fetus. IV. The Human Reproductive System A. Reproductive organs are called genitalia. 1. Genitalia are divided into: a. Primary genitalia (gonads that produce gametes) b. Secondary genitalia (other structures that aid in the reproductive process) B. Female Reproductive System 1. The primary genitalia are the ovaries. a. Ovaries are paired structures, about 3 cm long, in the peritoneal cavity. b. There is one ovary on each side of the uterus. c. Ovary is covered by a fibrous capsule called the tunica albuginea, made of cuboidal epithelium. d. Interior of the ovary is divided into the cortex, which contains the eggs, and the me5
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dulla, which contains blood vessels, nerves, and lymphatic tissue surrounded by loose connective tissue. e. Anatomy of the cortex is relatively complicated and is described during the discussion of physiology. f. Several ligaments suspend or anchor each ovary: i. Mesovarium suspends the ovary. ii. Suspensory ligament attaches the ovary to the lateral pelvic wall. iii. Ovarian ligament anchors the ovary to the uterine wall. g. Blood vessels, the ovarian artery, and the ovarian branch of the uterine artery travel through the mesovarium and suspensory ligament, supplying the ovary with oxygenated blood. 2. The Uterine Tubes a. The secondary genitalia are the fallopian tubes, the uterus, the vagina, and the external genitalia called the vulva. i. The passageway for the egg to get to the uterus ii. Begin as a large funnel, the infundibulum, surrounded by ciliated projections called fimbria; the infundibulum leads to a widened area, the ampulla, followed by a longer, narrower portion known as the isthmus; uterine tubes are connected to the superior portion of the uterus. iii. The tube is constructed of sheets of smooth muscle lined with highly folded ciliated simple columnar epithelium; the outside of the tube is covered by visceral peritoneum and suspended by a mesentery known as the mesosalpinx. 3. The Uterus a. In the pelvic cavity posterior and superior to the urinary bladder and anterior to the rectum b. Major portion of the uterus is called the body; rounded superior portion between the uterine tubes is the fundus, and narrow inferior portion is the isthmus. c. Cervix is a valvelike portion of the uterus that protrudes into the vagina; the cervical canal communicates with the vagina. d. Uterine ligaments i. The mesometrium attaches the uterus to the lateral pelvic walls. ii. The combination of the mesometrium and mesovarium is called the broad ligament. 6
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iii. The lateral cervical ligaments attach the cervix and vagina to the lateral pelvic walls. iv. The uterus is anchored to the anterior wall of the pelvic cavity by the round ligaments. 4. Layers of the uterine wall i. Perimetrium, outermost layer, the visceral peritoneum ii. Myometrium, middle layer, smooth muscle iii. Endometrium, inner lining, mucosa layer of columnar epithelium and secretory cells with two divisions: Basal layer, responsible for regenerating the uterine lining each month Functional layer sheds about every 28 days during menstruation. 5. Uterine blood supply i. Endometrium is highly vascular. ii. Blood is supplied by the uterine artery, which branches from the internal iliac arteries on each side. iii. Uterine arteries split into arcuate arteries, supplying the myometrium, and radial arteries, which supply blood to the endometrium. Straight, radial arteries supply the basal layer. Spiral radial arteries supply the functional layer, decaying and regenerating every month as part of the menstrual cycle and undergoing spasms that contribute to the shedding of the endometrium each month. iv. Blood returns to circulation via a network of venous sinuses. 6. Endometriosis i. Endometrial tissue escapes uterus. ii. Implants in abdominal cavity. iii. Builds up and decays each month with hormonal changes. iv. Causes scar tissue, reproductive problems, digestive problems. v. Most common cause of infertility 7. The Vagina a. A tube, approximately 10 cm long, running from the uterus to the outside of the body 7
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b. Receives penis during intercourse and allows for passage of menstrual fluid out of the uterus. c. Vagina is also known as the birth canal because its primary function is to allow the movement of a baby out of the uterus during childbirth. d. External opening of the vagina may be covered by a perforated membrane, the hymen. 8. The External Genitalia a. Collectively known as the vulva b. Labia majora i. Rounded fat deposits that meet and protect the rest of the vulva ii. Labia majora meet anteriorly to form the mons pubis, both covered by pubic hair. c. Pudendal cleft i. Opening between the two labia majora ii. Vestibule located within contains the urethra and vagina iii. Several glands surround the vestibule to keep it moist. iv. Lateral border of the vestibule is formed by the thin labia minora, which meet anteriorly to form the prepuce. d. Clitoris i. Posterior to the prepuce is the clitoris, a small erectile structure, 2 cm in diameter. ii. Like the penis, the clitoris engorges with blood during sexual arousal; increases in diameter, not length. iii. The clitoris has a shaft, a body, and a glans (tip). 8. Mammary Glands a. Milk production glands housed in the breasts b. At puberty, estrogen and progesterone stimulate breast development in girls. c. In adult females, the breast consists of 15–20 glandular lobes and lots of adipose tissue. d. Each lobe is divided into smaller lobules, which house milk-secreting sacs called alveoli when a woman is lactating. 8
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e. Milk made in the alveoli travels through a series of ducts and sinuses, eventually reaching the nipple. f. Milk production is controlled by the hormone prolactin when a woman is lactating. g. The areola is the darkened area that surrounds the nipple. V. Reproductive Physiology: Female A. The Menstrual Cycle 1. The female reproductive physiology is closely tied to a regulated cycle. 2. This cycle is normally regulated by hormones. 3. The menstrual cycle: a. Approximately 28 days, involving the ovaries and uterus b. Ovarian cycle involves the monthly maturation and release of eggs from the ovary. c. Uterine cycle consists of the monthly build-up, decaying, and shedding of the uterine lining. d. Cycles begin during puberty (menarche) and end in menopause in a woman’s 40s or 50s. e. Goal is to release an egg for fertilization and preparation of the uterus to receive the fertilized egg, nourishing the fertilized egg should pregnancy result. f. If pregnancy doesn’t result, the uterine lining sheds and the cycle begins again. g. Menses i. Menstrual cycle begins with the first day of menses. ii. Menstruation is the actual shedding of the endometrium, the “period” itself. iii. Menses refers to the time during which a woman is menstruating. iv. Menses usually lasts 4–5 days but can be longer or shorter in different women and can vary month to month in the same woman. v. Menstrual cycle occurs in four stages, usually over 28 days. h. Follicular stage (10 days) i. Follicle-stimulating hormone (FSH) is released by the pituitary gland. During this time, the endometrium is proliferating and the follicles are maturing in the ovary. i. Ovulation stage i. Pituitary stops producing FSH and starts producing luteinizing hormone 9
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(LH). ii. At day 14, the follicle ruptures and the ovum is released. j. Corpus luteum stage i. Corpus luteum secretes progesterone and continues to do so if the egg is fertilized, preventing further ovulation and maintaining the uterine lining. ii. This stage lasts about 14 days. k. Menstruation (menses) i. Occurs if the egg is not fertilized. ii. The corpus luteum diminishes progesterone production and the uterine lining is broken down and discharged over the course of 3–6 days. iii. Once menses is over, the endometrium begins to proliferate, readying itself for the egg that has been released from the ovary (ovulation). iv. From days 1–14, the oocyte, or egg cell, undergoes a number of developmental changes, getting ready for ovulation on day 14. i. Luteal or secretory phase i. If the oocyte is fertilized by sperm, it implants in the thickened endometrium. ii. If it doesn’t implant within a few days, the endometrium begins to decay, and menstruation occurs within 2 weeks. iii. The time between ovulation and menses is called the luteal, or secretory, phase because of the development of a structure called the corpus luteum in the ovary and the beginning of secretion in the uterus. B. Oogenesis, Follicle Development, and Ovulation 1. The process of egg production is called oogenesis. a. Oogenesis begins with the birth of oogonia, or egg stem cells, in the ovary. b. Oogonia undergo mitosis, producing millions of primary oocytes. c. Women have all the eggs they will ever have 5 months before they are born. 2. Primary oocytes a. Primary oocytes, because they are born via mitosis, still have 46 chromosomes. b. They must undergo meiosis to become gametes. c. Primary oocytes stay in a kind of suspended animation until puberty, when they finish developing. 3. Primordial follicles a. Primary oocytes surrounded by helper cells, called granulosa cells 10
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b. Hormonal signals during puberty cause some primordial follicles to enlarge and increase the number of granulosa cells. c. These enlarged cells are called primary follicles. 3. Secondary follicles a. At puberty, one primary follicle will become a secondary follicle. b. Secondary follicle will not complete its development unless it is ovulated and fertilized. c. Just before ovulation, the secondary follicle fills with fluid and moves toward the surface of the ovary; also called a graafian follicle. d. The fimbria of the uterine tubes brushes the surface of the ovary, causing the follicle to rupture. e. When the follicle ruptures, the egg (actually an oocyte) is released into the peritoneal cavity, and the fimbriae pull it toward the funnel, drawing it into the uterine tube (also called the oviduct or fallopian tube). 4. Fertilization a. As the egg travels down the uterine tube, it will either be fertilized or not be. b. If there are sperm present in the uterine tube and all the conditions are right, the sperm will penetrate the egg, fertilizing it and triggering the rest of the egg development. c. The successfully fertilized egg has 46 chromosomes and is now called a zygote. d. The zygote enters the uterus and implants into the proliferated endometrium, stopping the woman from menstruating. e. The ruptured follicle left behind in the ovary will become the corpus luteum and secrete hormones to help maintain the thickened endometrium to nourish the embryo. 5. Unfertilized eggs a. If zygote is not fertilized, it will not implant in the uterus. b. The uterine lining will begin to degenerate, and the women will have her period. c. The corpus luteum will become a corpus albicans and eventually disappear. C. Hormonal Control of Female Reproduction 1. Hormones from the hypothalamus, pituitary, and ovary control the female cycle. 2. Hierarchical control with negative feedback 11
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3. Four hormones control the menstrual cycle: estrogen and progesterone from the ovary, and luteinizing hormone (LH) and follicle-stimulating hormone (FSH) from the pituitary. 4. Puberty a. Estrogen and progesterone levels increase at puberty. b. The release of gonadotropin-releasing hormone (GnRH) from the hypothalamus causes an increase in the secretion of LH and FSH from the pituitary. c. FSH initiates the development of primary follicles each month, whereas LH triggers ovulation. 5. Follicular (proliferative) phase a. During the follicular phase, estrogen levels continue to rise as more and more is secreted by the developing follicle, stimulating proliferation of uterine lining. b. Estrogen exerts a positive influence on the hypothalamus, increasing the secretion of GnRH, thus increasing LH and FSH. c. This positive feedback loop continues, raising hormone levels until ovulation occurs. 6. Luteal (secretory) phase a. Once ovulation occurs, the feedback loop reverses itself. b. The corpus luteum begins to secrete progesterone as well as a little estrogen. c. Estrogen, under the influence of progesterone, exerts negative feedback on the hypothalamus and pituitary, decreasing GnRH, LH, and FSH secretion. d. Progesterone also exerts negative feedback on the hypothalamus and pituitary. e. Thus, during the luteal or secretory phase, LH, FSH, and estrogen levels drop while progesterone levels rise. f. These hormonal changes prevent another egg from maturing. g. For about 10 days after ovulation, progesterone levels remain high as the corpus luteum continues to secrete the hormone. h. Progesterone’s effect on the uterus is to maintain the build-up of the endometrium and to decrease uterine contractions. i. If no pregnancy results, the corpus luteum degenerates, and progesterone is no longer produced. j. Decreasing progesterone levels cause degeneration of the endometrium, followed by menstruation. k. Decreased progesterone levels release the hypothalamus and pituitary from their in12
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hibitory effects, FSH and LH levels begin to rise, and the cycle begins again. 7. Pregnancy a. If pregnancy does result, the implanted fertilized egg secretes a hormone called human chorionic gonadotropin (HCG). b. HCG stimulates the corpus luteum to keep secreting progesterone and a little estrogen to maintain the uterine lining. c. At about 3 months’ gestation, the placenta begins to secrete its own progesterone and estrogen, thus becoming an endocrine organ. A. Male Anatomy 1. Overview a. The primary genitalia, producing the male gamete, sperm b. Unlike female genitalia, the primary male genitalia are external. c. Secondary genitalia include the penis (sperm delivery organ), epididymis, vas deferens, urethra (sperm ducts), and several accessory glands, including the prostate gland, the seminal vesicles, and the bulbourethral glands. 2. Testes or testicles a. Paired organs suspended in a sac called the scrotum, hanging on both sides of the penis b. Each testis is surrounded by a serous membrane, called the tunica vaginalis, originating from the peritoneum. c. Deep in the tunica vaginalis is the tunica albuginea. d. The inside of the testes is divided into 250–300 wedges called lobules, each of which contain 1–4 seminiferous tubules. e. Seminiferous tubules are made of epithelium and areolar tissue, and contain sperm stem cells and sperm helper cells called Sertoli cells or nurse cells. 3. The Penis a. The penis is a sperm-delivery organ. b. The attached portion of the penis is called the root; the freely moving part is called the shaft or body. c. The tip of the penis, the glans penis, is covered by a loose section of skin called the foreskin unless a male has been circumcised. d. Internally, the penis contains the urethra, which is a transport passage for both sperm and urine, and three erectile bodies, tubes with a spongelike network of 13
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blood sinuses. 4. The Epididymis a. The epididymis is a comma-shaped duct on the posterior and lateral part of the testes. b. The tube is highly coiled and, if unravelled, would measure 6 meters long. c. It is made of pseudostratified ciliated epithelium and smooth muscle. d. Sperm mature here. 5. The Vas Deferens a. The vas deferens is a short tube, only 30 cm long. b. It is lined with ciliated pseudostratified epithelium, like the epididymis, but has a thick smooth muscle layer and is surrounded by a connective tissue layer called the adventitia. c. Runs from the scrotum to the penis via a relatively complicated pathway. i. From the anterior part of the scrotum as a pair of tubes, one on each side, into the abdominal wall (through the inguinal canal) and pelvic cavity, medially over the urethra and along the posterior bladder wall ii. Posterior to the bladder, the vas deferens joins the seminal vesicle to form the ejaculatory duct, which then passes through the prostate gland and empties into the urethra. iii. Between the scrotum and the inguinal canal, the vas deferens runs through a tube, with blood vessels and nerves, collectively called the spermatic cord. 6. Accessory glands a. Seminal vesicles, highly coiled posterior to the bladder, made of pseudostratified epithelium, smooth muscle, and connective tissue b. Prostate gland, a chestnut-sized gland surrounding the urethra just inferior to the bladder made up of a dense mass of connective tissue and smooth muscle with embedded glands c. Bulbourethral glands, pea-sized glands inferior to the prostate VI. Reproductive Physiology: Male A. Spermatogenesis 1. Sperm production, called spermatogenesis, is much less complicated than ovulation. a. Spermatogonia, sperm stem cells, undergo mitosis to form primary spermatocytes. 14
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b. Primary spermatocytes form two secondary spermatocytes. c. Spermatocytes complete meiosis to form spermatids. d. Spermatids go through a period of development to form immature spermatozoa (sperm). 2. Takes place in the testes in the seminiferous tubules. a. Spermatogonia line up against the walls of the tubules. b. Mature sperm cluster near the lumen of the tubules. 3. Sperm then travel from the seminiferous tubules to the epididymis, where the sperm spend about 2 weeks maturing and gaining the ability to swim. B. Hormonal Control of Male Reproduction a. Testosterone is the most important male sex hormone. i. In utero, HCG secreted by the placenta stimulates embryonic secretion of testosterone, masculinizing the fetus; those not exposed to testosterone become female. ii. After birth, there is little testosterone secreted until puberty. iii. At puberty, two hormonal changes occur that signal the beginning of maturity: a. Testosterone secretion by the testes increases. b. Testosterone enhances GnRH, and therefore FSH and LH, further enhancing testosterone production, creating a major positive feedback loop. (Prior to puberty, testosterone inhibits GnRH, but at puberty, the feedback loop reverses.) iv. Testosterone secretion at puberty brings about the male secondary sexual characteristic development, including: a. Body, facial, pubic hair growth b. Deepening of the voice c. Increased muscle and bone mass b. LH and FSH in males i. LH and FSH in males stimulate gamete development. ii. Regulated in the same way in males as in females iii. GnRH is released from the hypothalamus, which stimulates LH and FSH secretion from the pituitary. 15
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c. Estrogen i. Just as women have some testosterone, men have some estrogen. ii. The balance between the two hormones is important. C. Erection and Ejaculation 1. Erection: The erectile bodies in the penis (sponge like tissue with blood spaces) become engorged with blood, stiffening and expanding the penis. 2. Ejaculation: the expulsion of semen—sperm and assorted chemicals a. Smooth muscle contracts throughout the ducts and glands of the male reproductive system and propels the sperm from the epididymis into the vas deferens, and into the pelvic cavity; as the sperm passes the seminal vesicles, sugar and chemicals are added to the sperm. b. Sperm and chemicals enter the ejaculatory duct, passing though the prostate gland, where fluid is added, liquefying the semen and protecting the sperm from the acid environment of the vagina by secreting an alkaline substance. c. The semen passes by the bulbourethral gland, adding mucus to the semen. d. Finally, the semen enters the urethra and is carried outside the body. e. If a man is having sexual intercourse (coitus) with a woman and ejaculates, the sperm enter the vagina and make their way into the uterine tubes. f. The female reproductive system is not hospitable to sperm, and many sperm will not survive the journey. g. If there is an egg waiting to be fertilized, sperm will find the egg and attempt to penetrate it for fertilization. h. New research suggests that the egg is not a passive participant in fertilization but may actually engulf the sperm and even choose which sperm to allow inside. i. One sperm, and only one sperm, will fertilize the egg. VII. Pregnancy A. Pregnancy occurs when an egg is fertilized by the sperm and implants in the uterus. B. The development period is called the gestation period, approximately 40 weeks. C. A baby born before 36–37 weeks’ gestation is called a premature baby. D. The first 8 weeks of gestation, the developing infant is called an embryo, when the organs and systems are fundamentally formed. E. After 8 weeks, the infant is called a fetus. 16
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F. The growing fetus is nourished by a spongy structure called a placenta, attached to the fetus and the mother by the umbilical cord. G. The fetus is encased in a membranous sac called the amnion, containing amniotic fluid. H. Labor is the process by which the fetus is delivered through from the uterus the vagina. 1. Labor consists of three stages: a. Dilation stage; uterine smooth muscles begin to contract, moving the fetus down the uterus, causing the cervix to begin to dilate. b. Second stage-delivery i. Cervix is fully dilated to 10 cm, and the fetus is actually delivered. ii. Generally, the head presents first, called crowning, and the baby’s mouth is suctioned before it takes its first breath to prevent mucus from entering the respiratory tract. iii. A breech presentation: Buttocks appear first instead of the head. c. Last stage of labor, the placental stage, is the delivery of the placenta from final uterine contractions. I.
Contraception 1. The prevention of pregnancy is termed contraception and can be accomplished by a number of means, including an intrauterine device (IUD), spermicidal agents, birth control pills, or shields such as condoms or diaphragms.
2. Sterilization of the male can be accomplished by a procedure called a vasectomy in which the vas deferens are tied off to prevent sperm from traveling out of the penis during sexual intercourse. 3. Females may be sterilized via tubal ligation: The fallopian tube is cut or tied shut, preventing the sperm from getting to the egg and the egg from traveling to the uterus. VIII. Common Disorders of the Reproductive System A. Disorders of the Female Reproductive System 1. Amenorrhea: absence of menstruation 2. Dysmenorrhea: painful or difficult menstruation 3. Premenstrual syndrome (PMS): a variety of symptoms affecting many systems of the body 4. Vaginitis: inflammation of the vagina usually caused by a microorganism such as bacteria or yeast; many infections are caused by sexually transmitted diseases (STDs) that can be bacterial, viral, or fungal 17
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5. Cervical cancer: cancer of the cervix, diagnosed by a Pap test (named after George Papanicolaou), a smear of scrapings of the cervical cells to detect the presence of cancer cells 6. Ectopic pregnancy: implantation of a growing embryo in the uterine tubes 7. Abruptio placentae: premature separation of the placenta from the uterine wall; can result in fetal death if the baby isn’t quickly delivered. 8. Postpartum depression: a psychological state occurring after the delivery of the baby; may result in the mother harming herself or the baby in serious cases. 9. Mastitis: inflammation of the breast occurring at any age in males and females, but usually associated with lactating females 10. Breast cancer a. Breast cancer is the leading cause of death in women between the ages of 32 and 52, killing about 46,000 women a year. b. Men can also get breast cancer, but at a lower rate—estimated to be 1,000 cases in 2003 (compared to 182,000 female cases). c. Treatment may include any combination of complete mastectomy, lumpectomy, partial mastectomy, chemotherapy, or radiation therapy. d. Breast self-exam is the most important preventative measure, and all women should perform an exam monthly. B. Disorders of the Male Reproductive System 1. Erectile dysfunction disorder (EDD): The penis is unable to achieve a full erection; treatment includes medications to increase blood flow to the penis; inability to develop an erection is called impotency. 2. Cryptorchidism: failure of testes to descend into the scrotal sac; will result in infertility if uncorrected. 3. Hydrocele: an abnormal collection of fluid within the testes 4. Benign prostatic hypertrophy (BPH): enlargement of the prostate gland, commonly seen in males over age 50 5. Prostate cancer: a slow-growing cancer that also affects males in this age group and can be detected by a PSA test; early diagnosis increases survival rates. 6. Testicular cancer is a cancer that starts in the testes; most common in young or middle-aged men, and it is the most common cancer in men between 15 and 34. CLASSROOM ACTIVITIES 1. Have students trace the passage of sperm and ovum as they pass through the reproductive or18
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gans. 2. Have students write a paper and present it to the class. Suggested topics: teen pregnancy, HIV/AIDS, STDs, vasectomies, tubal ligations, various contraceptives, and infertility issues. TEACHING STRATEGIES 1. Many students are sexually active and some buy into silly myths they learned in their teen years. Use this opportunity to shine the light of reason onto these myths. Some myths include the idea that you can’t get pregnant the first time you have sex, that conception can’t occur if the man withdraws before ejaculation, and that contraceptives (especially condoms) protect them from all sexually transmitted diseases. 2. Some students may be uncomfortable talking about this topic in a mixed group of men and women. Keeping the language professional and tone of voice matter-of-fact and dealing with students’ questions honestly and openly can help make the situation more comfortable. FACTOIDS 1. Sexually transmitted diseases (STDs), once called venereal diseases, are among the most common infectious diseases in the United States today. More than 20 STDs affect more than 13 million men and women at a cost in excess of $10 billion dollars annually (www.niaid.nih.gov/factsheets/stdinfo.htm). 2. If you took all the DNA strands in your body and linked them together, they would measure 6– 8 feet. 3.
The FDA has replaced its previous drug-labelling categories that it used to classify the risks of using prescription drugs during pregnancy with three new subsections: Pregnancy, Lactation, and Females and Males of Reproductive Potential. The goal of the new labeling rule is to replace the previous overly simplistic and often misinterpreted grading system with explanations, based on available information, about the potential benefits and risks for the mother, the fetus, and the breastfeeding child (www.fad.gov).
ETHICAL DILEMMAS 1. Convicted pedophiles occasionally get the option of early release from prison if they agree to chemical castration, involving the injection of Depo Provera, which reduces the man’s ability to get an erection. Is this an ethically acceptable practice? What about the mother who is repeatedly convicted of child abuse—should she be forced to receive hormones to prevent pregnancy to keep her from abusing another child? 2. Pregnant women who abuse drugs negatively affect the health of their unborn fetus. Some localities arrest mothers when they come to the hospital to deliver their babies, or when they come in for prenatal care, if they have drugs in their system. Is this an ethical approach to the problem? Some say if mothers fear being arrested, they will fail to seek medical care prenatally or when it’s time to deliver. What do you think is right? How do we solve the problem and keep the fetus safe? What if the mother abuses alcohol and delivers a child with fetal alcohol syndrome—would you arrest her? What if the mother smokes? 19
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3. Some people believe it is cruel and unnecessary to circumcise baby boys. Others point to the high rate of penile cancer in uncircumcised men as a good reason to circumcise all baby boys. Those on the other side of the coin say we don’t do preventative mastectomies to pubescent girls; there shouldn’t be a need to circumcise boys. What do you think?
ANSWERS TO TEST YOUR KNOWLEDGE Test Your Knowledge 18–1 Answers, p. 394 1. c 2. b 3. d 4. c 5. b Test Your Knowledge 18–2 Answers, p. 398 1. d 2. b 3. c 4. b 5. b Test Your Knowledge 18–3 Answers, p. 402 1. b 2. c 3. b 4. c 5. b Test Your Knowledge 18–4 Answers, p. 405 1. c 2. c 3. b 4. b 20
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5. d Test Your Knowledge 18–5 Answers, p. 407 1. b 2. d 3. a 4. b Test Your Knowledge 18–6 Answers, p. 410 1. b 2. a 3. d 4. b ANSWERS TO THE CASE STUDY, P. 416–417 Maria’s rather vague symptoms could be caused by many different problems. The doctor could try ultrasound, CAT scan, MRI, or even x-ray to look for problems in Maria’s abdomen. Pain in her abdomen and back could be the result of a tumor or a herniated disk or many other problems. The doctor might suggest a colonoscopy to check for problems in her digestive system or a cystoscopy to check for abnormalities in the urinary bladder. The doctor should also do a Pap smear. However, Maria’s symptoms mainly point to endometriosis, the abnormal growth of endometrial tissue outside the uterus. Her pain and other symptoms are part of a group of often vague symptoms associated with endometriosis, the most common cause of infertility. Unfortunately, the only way to tell for sure whether Maria has endometriosis is with a laparoscopy, exploratory abdominal surgery. ANSWERS TO REVIEW QUESTIONS, P. 485 Multiple Choice 1. b, 2. a, 3. d, 4. c, 5. a, 6. d Fill in the Blank 1. erection; ejaculation 2. seminal vesicles; prostate 3. Meiosis (reduction/division) 4. negative 5. fertilization 6. Endometriosis 21
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Short Answer 1. Sperm are made in the seminiferous tubules of the testes. They mature in the epididymis. From the epididymis, sperm flow up the vas deferens and into the body. They pass the seminal vesicles and enter the urethra. Then sperm travel through the prostate and eventually out through the end of the penis during ejaculation. The sperm will travel up the vagina into the uterus, eventually reaching the fallopian tubes, where fertilization takes place if an egg is present. 2. Four hormones control the female reproductive cycle: estrogen, progesterone, luteinizing hormone (LH), and follicle-stimulating hormone (FSH). (The levels of LH and FSH are controlled further by GnRH from the hypothalamus.) At puberty, estrogen and progesterone are secreted by the ovary, increasing LH and FSH secretion from the pituitary. FSH stimulates follicles to mature, and LH stimulates ovulation. The follicular (proliferative) phase of the menstrual cycle is characterized by increased estrogen, which causes increased FSH and LH, which causes increased estrogen, in a massive positive feedback loop. This positive feedback loop causes ovulation and proliferation of the endometrium. Once ovulation occurs, the feedback loop reverses itself. This begins the luteal (secretory) phase. The leftover ruptured follicle secretes progesterone and a bit of estrogen. Progesterone causes the feedback loop to become negative. Thus, LH, FSH, and estrogen secretion decrease. Therefore, another follicle doesn’t mature; another egg doesn’t ovulate; and the lining of the uterus is maintained for about 10 days. After 10 days, the progesterone levels decrease and the endometrium is shed if fertilization has not occurred. The decrease in progesterone levels also allows estrogen, LH, and FSH to rise again, eventually stimulating ovulation, and the cycle begins again. 3. Labor consists of three stages. In the dilation stage, the uterine smooth muscle begins to contract, thereby moving the fetus down the uterus and causing the cervix to begin to dilate. When the cervix is completely dilated (10 centimeters), the second stage (expulsion) begins, during which the baby is actually delivered. The last stage of labor is the placental stage, in which the placenta or afterbirth is delivered because of final uterine contractions. 4. Eggs and sperm, with only half as many chromosomes as other cells, are produced by meiosis in the gonads, testes in males and ovaries in females. Fertilization occurs, resulting in a zygote. The zygote undergoes millions of rounds of mitosis and development within the female to change from an embryo to a fetus (the infant that is not born yet). Eventually, after years of mitotic growth, an adult is formed. That adult is capable of making eggs and sperm, and the cycle continues. 5. The process by which eggs are produced is called oogenesis. Oogenesis begins with the birth of oogonia, or egg stem cells, in the ovary. The oogonia undergo mitosis, producing millions of primary oocytes during fetal development. Primary oocytes undergo meiosis. The primary oocytes stay in a kind of suspended animation until puberty, when they finish developing. These primary oocytes eventually are surrounded by helper cells, called granulosa cells. Once surrounded by granulosa cells, the primary oocyte and surrounding cells are known as primordial follicles. These primordial follicles stay dormant until puberty. Hormonal signals during puber22
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ty cause some primordial follicles to enlarge and increase the number of granulosa cells. These enlarged cells are then called primary follicles. Once a girl reaches puberty, one primary follicle will become a secondary follicle. The secondary follicle will not complete its development unless it is ovulated and fertilized.
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Name _______________ CHAPTER 18—WORKSHEET Multiple Choice 1) The reproductive structures that produce gametes are called the: A) primary genitalia. B) secondary genitalia. C) tertiary genitalia. D) quaternary genitalia. 2) The _____ is the inner lining of the uterus, which proliferates each month and is shed if pregnancy does not occur. A) cervix. B) endometrium. C) myometrium. D) fundus. 3) The muscular layer of the uterus is called the: A) cervix. B) endometrium. C) myometrium. D) fundus. Matching Match each of the following female structures with the appropriate description. 4) _____ Uterus 5) _____ Ovaries 6) _____ Fallopian tubes 7) _____ Vagina 8) _____ Mammary glands 9) _____ Clitoris 10) _____ Perineum 24
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11) _____ Vulva 12) _____ Hymen 13) _____ Follicle 14) _____ Corpus luteum A. Produce female hormones and eggs. B. Serves as the birth canal during labor. C. A membrane that may surround the opening to the vagina D. The “womb”; the location where pregnancy develops E. Carry eggs from the ovaries to the uterus. F. The area between the vagina and the anus G. An egg and its associated helper cells H. Produce milk after a baby is born. I. The remnants of the follicle after ovulation; secretes progesterone. J. Erectile tissue that becomes engorged with sexual arousal K. A collective term for all the external female genitals Matching Match each phase of the female menstrual cycle with the appropriate description. 15) _____ Follicular 16) _____ Ovulation 17) _____ Luteal phase 18) _____ Menses A. When the endometrial lining is shed; a portion of the follicular phase B. Period of time from ovulation until menstruation; corpus luteum develops in the ovary, and the uterus begins secretion C. Period of time where follicles are maturing in the ovary and endometrium is proliferating D. When the ovary releases a mature egg (oocyte) Matching Match each structure with the appropriate description. 25
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19) _____ Testes 20) _____ Epididymis 21) _____ Scrotum 22) _____ Vas deferens 23) _____ Urethra 24) _____ Penis 25) _____ Prepuce 26) _____ Prostate gland 27) _____ Seminal vesicles 28) _____ Bulbourethral gland A. The sac of skin that contains the testes B. Produce sperm and testosterone. C. The tube that carries sperm from the scrotum up into the pelvic cavity D. The “foreskin” that covers the glans penis E. The donut-shaped gland that surrounds the urethra; produces seminal fluid. F. Two tiny, pea-sized glands located inferior to the prostate G. A dual-purpose tube that serves as the exit for seminal fluid and urine to leave the body H. The comma-shaped structure at the back of each testis where sperm mature I. Two highly coiled glands located posterior to the bladder; secrete seminal fluid. J. Composed of erectile tissue; engorges with blood during sexual arousal; facilitates delivery of sperm into the female reproductive tract. ANSWER KEY Chapter 18—Worksheet 1) A 2) B 3) C 4) D 5) A 26
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6) E 7) B 8) H 9) J 10) F 11) K 12) C 13) G 14) I 15) C 16) D 17) B 18) A 19) B 20) H 21) A 22) C 23) G 24) J 25) D 26) E 27) I 28) F
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Name _______________ LABELING ACTIVITY INSTRUCTIONS: Please label the following diagram.
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LABELING ACTIVITY ANSWER KEY
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Colbert A&P 3E IM Chapter 19
Chapter 19 THE JOURNEY’S END: NOW WHAT? LEARNING OUTCOMES Discuss the relationship between forensic science and anatomy and physiology. Relate the anatomy and physiology changes in the process of aging. Describe the concept of wellness and personal choices. List and describe wellness concepts for each body system. Discuss cancer prevention and treatment. Dazzle your friends with amazing anatomy and physiology facts.
MULTIMEDIA FOUND ON THE POWERPOINT LECTURE OUTLINE 1. Lead Poisoning Animation (slide 15) 2. Carpal Tunnel Syndrome Video (slide 70) 3. Skin Cancer Video (slide 78) 4. Eating Disorders Video (slide 92) 5. Audiology Video (slide 101) 6. AIDS Video (slide 123) 7. Gonorrhea Video (slide 124) 8. Herpes Video (slide 125) 9. Criminalists Video (slide 147) 10. Mental Health Professionals Video (slide 148) 11. Physician Assistants Video (slide 149)
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LECTURE OUTLINE I. Introduction A. The basics of anatomy and physiology you have learned will act as a foundation for life encounters, both personal and professional. B. This chapter looks at some small examples of how anatomy and physiology play important roles in many areas. II. Forensic Science A. Forensic science is the application of science to law. B. A forensic scientist often searches for and examines physical traces to establish or exclude a criminal suspect and the suspect’s association to a victim. C. Forensic scientist use both physical science (such as anatomy and physiology) and social sciences. D. Disease Detection 1. Ancient Egyptians were stricken with TB, which was discovered by examining (using bone scouring) the ends of long bones of skeletal remains of ancient Egyptians. E. Primitive Surgery 1. A 400-year-old drill hole in skull from Jamestown, Va. F. Remains Identification 1. Video skull–face superimposition allows experts to mark a skull with pins at 30 specific structural landmarks and generate a computer comparison of those 30 points to a picture of that person when alive. 2. Dental records can be compared with the teeth, if found, in a skull for identification purposes. G. Murder Most Foul! 1. Hair a. A person’s health and habits b. Can reveal the race of an individual. c. DNA and blood type can be discerned. d. Hair stores information about substances a person ingested or was exposed to; because hair grows slowly, it can act as a timeline. 2
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H. Fingerprints 1. No two fingerprints are exactly alike. 2. Even identical twins have different fingerprints. 3. Fingerprints were discovered in the 1600s and were first used in 1880 to solve crimes. I. DNA Fingerprinting 1. DNA can be used to identify individuals. 2. Sampled from blood, semen, bones, or even a very tiny soft tissue sample 3. DNA molecules are split into pieces and separated using electrical currents, and samples from known individuals of interest are compared with DNA found at the scene. 4. It is now standard to use this technology to solve rape and murder cases. 5. Helped determine that Thomas Jefferson or a male relative did father children with his slave, Sally Hemmings. 6. Used to identify many of the victims from the 9/11 terrorist attack III. Geriatrics A. Increase in elderly populations because of: 1. Safer workplaces 2. Healthier lifestyles 3. Effective vaccines and medications 4. Access to improved health care B. Geriatric patients differ in many ways from other populations. C. The term elderly can be misleading; classification system: 1. 65–75—younger old 2. 76–84—older old 3. Over age 85—elite old D. We do not age uniformly. E. General Body Changes 1. 1% decline in function of most body systems per year after age 30. 3
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2. Decrease in the ability to maintain homeostasis 3. Decrease in the ability to handle stressors 4. Disease processes may accelerate the loss of body reserves. 5. Declines in vision, hearing, and, possibly, mental abilities 6. Total body water declines, leading to faster dehydration and slower excretion rates of medications. 7. From age 20 to 70, there is a loss of lean body mass. 8. Increase in body fat 9. Bone density usually peaks at age 35. a. Women may experience a 1% to 2% loss of bone in the first 5 years following menopause. b. In general, we see a 1% decline in bone mass between the ages of 55 and 70. c. After age 70, bone loss is 0.5% per year. F. Gustatory changes 1. Changes in GI system are barriers to good nutrition, including: a. Loss of teeth, ill-fitting dentures b. Difficulties swallowing c. Decrease in salivary secretions d. Decreases in digestive juices and secretion e. Decreased nutrition absorption f. Decreased bowel function g. Decreased taste perception G. The Brain and Nervous System 1. The elderly have slower reaction time, increasing the likelihood of motor vehicle accidents, falls, burns, and other accidents. 2. Pain is often a problem in the elderly, leading to an overall decrease in the quality of life, including impaired sleep, decreases in socialization, confusion, depression, malnutrition, polypharmacy, and impaired ambulation. 3. This leads to increasing health care costs. 4.
Pain management 4
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a. Geriatric patients are often undermedicated for pain because they are debilitated, are cognitively impaired, have a history of substance abuse, or are unable to effectively relate how they feel. b. Sometimes poor pain management is the result of health care professionals who cannot recognize indicators of pain. c. Behavioral changes related to pain include: i. Changes in personality, such as becoming agitated, quiet, withdrawn, sad, confused, depressed, and/or grumpy ii. Loss of appetite iii. Screaming, swearing, name calling, grunting, and/or noisy breathing iv. Crying, rocking, fidgeting v. Splinting or rubbing a sore area, wincing vi. Cold, clammy, pale skin H. The Cardiovascular System 1. Changes in the aging cardiovascular system include: a. Calcification of the heart valves, decreasing their efficiency b. Lessening of flexibility of blood vessels, leading to clogging c. Inability to deal with blood pressure changes, resulting in elevated blood pressure d. Decrease in cardiac output e. A 25% decrease in maximum heart rate I. The Genitourinary System 1. Between ages 20 and 80, we lose about 50% of our renal function. 2. This becomes especially significant when you think of the number of medications this age group uses. 3. Reduced metabolism of medications can lead to an accumulation of the drug to harmful or toxic levels. 4. There is an increase in incontinence (loss of bladder control) in this age group. J. The Integumentary System 1. Changes in the integumentary system in the elderly include: a. Loss of skin elasticity 5
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b. Increased skin delicacy c. Multiple skin lesions d. Increased incidence of skin cancer 2. Sun exposure, smoking, and medications like corticosteroids can accelerate these changes. K. Polypharmacy 1. Polypharmacy, the administration of many drugs at the same time, is a major concern in this age group. 2. Contributing factors include the fact that they may see many specialists for a variety of diseases, and no one doctor oversees the process. 3. These multiple diseases have competing therapeutic needs, and the combinations of drugs can cause life-threatening situations. 4. Aging can also affect the rate of drug absorption, distribution, metabolism, and excretion from the body. IV. Wellness A. Personal choices affect health. B. Eating properly, exercising within reason, smoking, using drugs and alcohol, and living or working in a dangerous environment are all important decisions. C. Individual accountability and informed choices are key concepts in deciding your lifestyle. D. Peer pressure can be negative or positive. E. Read and critically analyze what you read: There is a lot of “junk” science available that is more opinion than fact. F. The Nervous System 1. Stress is a natural part of life—a good and necessary evil, a motivator, helping you to protect yourself. 2. When stress becomes chronic, and you can’t effectively deal with it, it can affect some or all of your body’s various systems. 3. Stress imbalance can cause eating disorders, digestive problems, decreased immune response, decreased memory and work capacity, sleep problems, joint and muscle aches, heart problems, and personality changes. 4. Some can be life-threatening. G. The whole patient 6
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1. When assessing a patient, we too often look at the disease instead of the whole picture. 2. The whole picture includes not only other systems of the body but also the mental and spiritual aspects of a person. 3. Mental illness carries a stigma, but it’s no different than other diseases requiring help to resolve. H. The Skeletal System 1. Diet is extremely important to the growth and protection of your bones. 2. A diet rich in calcium and vitamins helps maintain good bone growth and development. 3. Weight-bearing exercises are beneficial as well. 4. Even with a good diet and exercise plan, repetitive motion injury is a real possibility. a. Carpal tunnel syndrome I. The Muscular System 1. Proper exercise and diet will help develop and maintain properly functioning muscles. 2. There are many types of muscle training programs, and it is important to find what is best for your needs and outcome. 3. Muscle enhancement drugs are dangerous and have serious side effects. J. The Integumentary System 1. Proper diet and hydration are important for the functioning of the integumentary system. 2. Smoking causes premature aging of the skin. 3. Some sun exposure produces vitamin D, but limiting the amount of sun exposure is important to prevent skin cancer; minimize time in the sun between 10 a.m. and 4 p.m., when the sun is the most powerful; cover as much skin as possible; protect the eyes with sunglasses; and use a good SPF sunblock to reduce risk. 4. Some forms of skin cancer are treatable; others can be lethal. K. The Cardiovascular System 1. A heart-healthy diet low in saturated fats and high in fiber, rich in fruit and vegetables, will maintain an optimally healthy cardiovascular system. 2. The proper level of regular exercise helps tone the heart muscle for proper functioning; walking 30 minutes a day, three or four times a week, individualized to specific requirements, is all that’s required. 3. Tobacco, alcohol, and other drugs can have a negative effect on this and other systems. 7
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L. The Respiratory System 1. Smoking a. Number one preventable cause of respiratory disease b. Increases the occurrence of lung infections and colds as well as sinus infections. c. Associated with 80% of all lung cancers d. Affects the heart, reducing available oxygen to the heart muscle. e. With alcohol consumption, increases the occurrence of stomach and mouth cancers. 2. Outdoor and indoor pollution can lead to respiratory problems. 3. Respiratory damage can be caused by occupational hazards. 4. The lungs respond to irritants by narrowing the airways to minimize exposure, leading to breathing difficulties. M. The Gastrointestinal System 1. A proper diet is critical for growth, development, and general health. 2. Lack of nutrients, leading to malnourishment, can adversely affect health. 3. Vitamin and mineral supplements can be helpful, but it is best if the diet contains all essential ingredients. 4. Fat-soluble vitamins (A, D, E, and K) can build up in the body to toxic levels if taken in excess. N. The Endocrine System 1. Proper diet and exercise assist the endocrine system. 2. Performance-enhancement drugs, like anabolic steroids used to increase strength and endurance, can have serious side effects including kidney damage, liver damage, increased risk of heart disease, irritability, and aggressive behavior. 3. Women taking steroids can develop facial hair and deeper voices in addition to the other effects. 4. Some of these effects can be permanent. O. The Sensory System 1. Proper diet, hearing and sight protective devices, and periodic eye and ear exams are needed for sensory system wellness. 2. Wearing hearing protection during loud noise extends the functional life of your ears; damage to the ear is cumulative. 8
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3. Protective eyewear should be worn any time there is risk of eye injury, including polarized sunglasses when glare from the sun could damage the unprotected eyes. P. The Immune System 1. Proper diet and exercise are important to optimal functioning of the immune system. 2. The best way to protect yourself and your patients is with handwashing; for handwashing to be effective, it requires running warm water, soap, and friction lasting for at least 20–30 seconds; singing, “Row, Row, Row Your Boat” twice takes about 20 seconds and is a good timing device—especially for teaching children how to wash their hands. 3. Wash your hands before and after contact with patients, eating, and using the bathroom, and any time your hands become soiled. 4. Standard Precautions Guidelines a. Another way to protect yourself and others from the spread of pathogens is by following Standard Precautions Guidelines. b. These guidelines assume that everyone is potentially infectious. c. Follow standard guidelines, like wearing gloves whenever you are in contact with bodily secretions. 5. Current Immunizations a. Keeping immunizations current is another protective device for the immune system. b. Immunization schedules are recommended by the Centers for Disease Control and Prevention (CDC), the American Academy of Pediatrics (AAP), and the American Academy of Family Physicians (AAFP). c. Immunizations are not given only during childhood; influenza vaccinations should be received yearly, tetanus toxoid vaccinations every 5–10 years, and everyone working in health care should be immunized against hepatitis. d. Immunizations are particularly important to the very young and very old, who are most susceptible to disease. 6. Antibiotics a. Proper use of antibiotics is also important to maintaining immune system wellness. b. Overuse of antibiotics can lead to problems. c. Antibiotics are not effective against viruses and can harm normal bacteria such as those located in the intestines. d. Overuse of antibiotics in children can lead to improperly developed immune systems. 9
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e. Taking antibiotics improperly and not following the directions on the label can lead to the development of “superbugs” by allowing a few bacteria to survive and alter their DNA, making them resistant to that particular drug; this can lead to outbreaks of drug-resistant infections. Q. The Reproductive System 1. Pregnancy a. Mothers who smoke tend to have low-birth-weight infants, an increased risk for premature births, and a higher rate of SIDS (sudden infant death syndrome). b. Secondhand smoke is dangerous in the home, leading to slower lung development in children and increased incidence of bronchitis, asthma, and ear infections (otitis media). c. It is important to provide the pregnant mother with important vitamins, minerals, and nutrients for the developing fetus and to maintain the health of the mother. d. Calcium is particularly important because if the diet is lacking in calcium, the fetus will rob calcium from the mother’s teeth and bones, decreasing the integrity of her system. e. Spina bifida, a congenital condition of the fetus, can be prevented by adequate intake of folic acid (B complex). f. Alcohol must be avoided in pregnancy because of its effect on the fetus’s nervous system. 2. Sexually transmitted diseases (STDs) a. STDs are a growing problem and can have serious effects on the reproductive system and lethal effects on the body. b. Various diseases and organisms can be transmitted through unprotected sex (including oral sex). c. Although condoms are not foolproof, they are the best means for reducing the risk of transmitting STDs; the only foolproof method is abstinence. V. Cancer Prevention and Treatment A. All body systems can be invaded by cancer. B. Cancer is the runaway reproduction and spread of abnormal cells, a very complicated disorder. C. Each type of cancer is named for the type of cell running amok and has its own unique characteristics. D. Medical science continues to learn more about cancer every year and develop better treatments. 10
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E. However, early detection is the best predictor of outcome. F. Cancer triggers 1. Any number of triggers can make a cell cancerous, including genes, radiation, sunlight exposure, smoking, fatty foods, viruses, and chemical exposures. 2. Some, like genes and viruses, can’t be avoided; others can be reduced by changing lifestyle; melanoma risk is greatest for those living closest to the equator; melanoma can be prevented by decreasing exposure to UV light. 3. Many types of cancers can be prevented or managed with a healthy diet and exercise. VI. More Amazing Facts 1. Senior citizens are more prone to food poisoning because of decreased senses of smell and taste and reduced acidity of digestive juices. 2. Nerve impulses can travel up to 426 feet per second! 3. Approximately 480,000 people die annually from smoking-related diseases; this is equivalent to a jumbo jet full of people crashing every day without any survivors. 4. A healthy kidney filters 180 quarts of fluid every day, and it is only 4 inches long, 2 inches wide, and 1 inch thick. 5. Hair can grow a quarter inch per day—faster during the day and during the summer months. 6. You use about a half pint of oxygen per minute at rest. 7. Everyone has one nare (nostril) that is larger than the other. 8. Your heart beats over 36 million times a year! 9. You possess over 16,000 miles of capillaries! 10. Viruses are constantly mutating, so immunity doesn’t last a lifetime! 11. You have between 10,000 and 150,000 hairs—just on your head! Each strand of hair can support approximately 100 grams of weight so, at least in theory, a full head of hair could support the weight of two African elephants! 12. Research suggests that vitamins and minerals from natural food sources are better utilized than synthetic pills, but pills are better than nothing. 13. The horns on a bull are composed of the same material that makes up your finger- and toenails. 14. You have about a quarter of a million sweat glands on your feet. 15. Based on current research of fibroblasts and their ability to double before they lose their 11
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ability to accurately divide, we have the potential to live to 120 years of age. 16. Your eyes can see approximately 7 million shades of color. 17. Urine is sterile, so it can be used to clean out a wound. 18. The ability to roll your tongue into a tube is inherited, and not everyone can do it. 19. Cavities and poor oral hygiene can lead to diabetes and heart attacks; some experts believe daily flossing can add 6.4 years to your life because bacteria growing in the mouth can escape into the bloodstream and cause problems in other parts of the body; a person with poor oral hygiene has a 4 times greater risk of a stroke and 14 times greater risk of a heart attack. 20. Current research indicates that stomach cancer, affecting 33,000 Americans annually, may originate from bone marrow cells that enter the stomach to repair damage to the stomach lining. 21. A recent study showed that individuals who walk uphill clear fats from their blood faster, whereas downhill hiking reduces sugars more readily and improves glucose tolerance; hiking of any kind removes LDLs. This research may affect exercise recommendations for various conditions. 22. CIPA (congenital insensitivity to pain with anhidrosis) is a rare genetic disorder that affects the development of small nerve fibers that transmit the sensation of pain, heat, and cold to the brain; there are only 17 known cases in the United States. Clients with CIPA are at great risk of injury, such as from burns, because they don’t know they’re in danger; because they don’t feel heat or cold, they don’t sweat! Biting their tongue when eating is common. CLASSROOM ACTIVITIES 1. Assign students to watch an episode of the television show CSI: Crime Scene Investigation, or show an episode during class. Discuss the types of tests and studies done on the show and the reality of this level of investigation. 2. Have students bring pictures of their grandparents to class. The pictures should represent their grandparents at different ages. Discuss the visible signs of aging seen in the pictures. 3.
Try your hand at creating and matching a DNA fingerprint by visiting NOVA (www.pbslearningmedia.org). Search on DNA fingerprinting.
TEACHING STRATEGIES 1. Have fun with this module. Allow discussions to follow whatever path the students take. The section of this chapter you emphasize will depend on the program you’re teaching and the needs of the students. 2. Use this opportunity to also discuss how the students’ health will affect their clients, and review 12
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the need to reduce communicable illnesses by following the wellness recommendations in this chapter. FACTOIDS 1. Did you know our noses grow as we age? It’s true. Because the nose is largely cartilage, and connective tissue loosens as we age, the nose actually grows longer as we age. 2. Refer to all the facts at the end of this chapter—they’re interesting and fun to discuss in class. ETHICAL DILEMMAS 1. We have an aging population, sometimes referred to as the graying of America, because the Baby Boomers are on the cusp of becoming seniors. It is certainly an accepted fact that the older we grow, the more medical care we require. At the same time, there is a serious nursing shortage, predicted to worsen in the next 10 years because many nurses are Baby Boomers and will retire. How do we handle this situation? 2. With the many concerns regarding terrorism, it has been suggested that we should have a national database of DNA fingerprints. Many people have serious concerns about this breach of individual privacy. Discuss the ethics of this suggestion. ANSWERS TO TEST YOUR KNOWLEDGE Test Your Knowledge 19–1 Answers, p. 423 1. c 2. d 3. b 4. d 5. b Test Your Knowledge 19–2 Answers, p. 426 1. d 2. c 3. b 4. a Test Your Knowledge 19–3 Answers, p. 436 1. d 2. c 3. a 13
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4. c 5. a ANSWERS TO THE CASE STUDY, P. 439 Because Riga and Mortis are identical twins, their DNA will be identical, so DNA fingerprinting will not be able to prove the identity of the real murderer. However, identical twins generally do not have identical fingerprints. If there were fingerprints left at the scene, they might reveal the identity of the guilty party. ANSWERS TO REVIEW QUESTIONS, P. 439–440 Multiple Choice 1. b, 2. c, 3. d, 4. b, 5. b Fill in the Blank 1. age; sex; activity level 2. A; D; E; K 3. genital warts 4. Pap test Short Answer 1. Skin cancer can be prevented by avoiding UV exposure. Methods include applying sunscreen; wearing a hat, long sleeves, and pants; and keeping out of the sun during peak hours. 2. Abstinence (no sex) and monogamy (sex with only one partner who is not having sex with others) are the best ways to prevent STDs. Some STDs can also be prevented by the use of a condom, but many STDs can be transmitted despite condom use. 3. Handwashing is the best way to prevent the spread of infection. In addition, following the Standard Precautions Guidelines, having current immunizations, and taking antibiotics properly can help prevent spread of infection. 4. Forensic science uses both the physical and social sciences to solve crimes by such methods as detailed anatomical studies, chemical analysis of fluids, fingerprints, and DNA fingerprinting.
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Name _______________ CHAPTER 19—WORKSHEET Multiple Choice 1) Mrs. S., your 85-year-old neighbor, always seems to wear a gallon of perfume. Based on your understanding of the normal aging process, you know that this is probably because: A) Her sense of smell has deteriorated with age. She cannot smell the perfume unless she wears a lot. B) Her cognitive function has deteriorated with age. She no longer understands what a normal amount of perfume is. C) Her muscle coordination has deteriorated with age. When she puts on perfume, she no longer has good control over what comes out of the bottle. D) The multiple medications that are commonly taken by elderly individuals can interact with perfume, intensifying its aroma. 2) Compared to the male pelvis, the female pelvis: A) is wider. B) is lighter. C) has a larger pubic angle (of 100 degrees or greater). D) All of the above 3) As we age, we generally: A) lose muscle mass. B) gain fat. C) lose bone density. D) All of the above 4) The senses of smell and taste naturally _____ as we age. A) improve B) deteriorate C) stay the same D) disappear entirely Fill in the Blank 5) _____ records can be compared with teeth in the skull to help identify a body. 15
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6) If a shaft of hair still has the follicle attached, it may contain _____ that can be further analyzed. 7) During DNA _____, DNA molecules are split into pieces, separated using electric currents, and then compared with DNA samples from known sources (relatives of victim, suspects in crime, etc.). 8) After the age of 30, we generally see a _____ % per year decline in the function of most body systems. 9) Bone density usually peaks at age _____ in males and females. 10) In some geriatric patients, changes in their sense of taste and smell may cause orange juice to taste _____. 11) Many geriatric patients have slower _____ times. This can result in increased risk for motor vehicle accidents, falls, and other accidents. 12) Cardiovascular changes in the elderly include _____ cardiac output. 13) Between the ages of 20 and 80, we lose about _____ % of our renal function. 14) The administration of many drugs at the same time is called _____. 15) A diet rich in the mineral _____ is important to help maintain strong bones. 16) To help protect your skin from the sun, try to minimize sun exposure between the hours of _____ and _____. 17) Current recommendations suggest that you try to get at least 30 minutes of exercise, ____–_____ days a week. 18) _____ is the number one preventable cause of respiratory disease. 19) _____-soluble vitamins (like vitamins A, D, E, and K) can build up to toxic levels in the body if taken in excess. 20) Women taking _____ can develop facial hair and deeper voices. True or False 21) T F Identical twins will have identical fingerprints. 22) T F In the elderly, skin elasticity increases. 23) T F Spina bifida can be prevented with adequate dietary folic acid. Short Answer/Essay 24. List two factors that could create barriers to good nutrition in geriatric populations. ______________________________________________________________________________ ______________________________________________________________________________ 16
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______________________________________________________________________________ 25. List two behavioral changes that could indicate a geriatric patient’s pain control is inadequate. ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ANSWER KEY Chapter 19 – Worksheet 1) A 2) D 3) D 4) B 5) Dental 6) DNA 7) fingerprinting 8) one 9) 35 10) metallic 11) reaction 12) decreased 13) 50 14) polypharmacy 15) calcium 16) 10 a.m.; 4 p.m. 17) 5; 7 18) Smoking 19) Fat 20) steroids 21) F 17
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22) F 23) T 24) Answers may include: loss of teeth, difficulty swallowing, decreased saliva, decreased digestive juices, decreased absorption of nutrients, decreased bowel function. 25) Answers may include: change in personality; decreased appetite; screaming; swearing; grunting; noisy breathing; crying; rocking; fidgeting; splinting or rubbing the sore area; wincing; and skin that is cold, clammy, or pale.
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