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Campbell Essential Biology, 6e (Simon/Dickey/Hogan/Reece)
Chapter 24 The Body’s Defenses
Chapter 24 Learning Outcomes
24 Biology and Society: Herd Immunity
24.1. Define herd immunity, and explain how decreasing vaccination rates can threaten herd
immunity.
24.1 An Overview of the Immune System
24.2. Define the immune system, and distinguish between innate and adaptive immunity.
24.2 Innate Immunity
24.3. Compare and contrast external and internal innate defenses.
24.4. Describe the inflammatory response, the role of histamine, and the effects of drugs such
as ibuprofen.
24.3 The Lymphatic System
24.5. Compare the circulatory and immune functions of the lymphatic system, and explain how
lymph is formed.
24.4 Adaptive Immunity
24.6. Explain how the immune system recognizes foreign substances with antigens.
24.7. Describe the process of clonal selection, and explain how effector cells and antibodies are
produced and what their functions are.
24.8. Compare and contrast the roles of cytotoxic T cells, helper T cells, and B cells in the
immune response.
24.9. Explain how the immune system has “memory.”
24.10. Explain how vaccinations can prevent disease.
24.5 Immune Disorders
24.11. Define an allergen, an allergy, and anaphylactic shock. Describe the two steps of an
allergic reaction.
24.12. Compare and contrast autoimmune diseases and immunodeficiency diseases.
24 Evolution Connection: Viral Evolution versus the Flu Vaccine
24.13. Explain why the preparation of flu and HIV vaccines is especially challenging.
Global Learning Outcomes
1. Demonstrate an understanding of the principles of scientific inquiry.
2. Demonstrate the ability to think critically and employ critical-thinking skills.
3. Read and interpret models, graphs, and data.
4. Demonstrate the quantitative skills needed to succeed in biology.
5. Demonstrate an understanding of the impact of science on society.
6. Evaluate the credibility of scientific information from various sources.
7. Demonstrate the ability to make connections between concepts across biology.
8. Communicate effectively in writing.
9. Apply the scientific method to interpret information and draw conclusions.
24.1 Multiple Choice Questions
1) Herd immunity fails when what percentage of the population is NOT vaccinated?
A) 1%
B) 5%
C) 10%
D) 50%
2) Which of the following is one of the body’s first lines of defense against infection?
A) antibodies
B) obstacles such as skin and mucous membranes
C) increased production of certain hormones
D) decreased heart rate
3) Slugs produce mucus all over their bodies that helps keep them moist and helps them move.
The mucus also can protect the slugs from pathogens. A slug’s mucus is a component of which
part of the immune system?
A) internal innate immunity
B) external innate immunity
C) adaptive immunity
D) lymphatic system
4) What kinds of cells engulf whatever foreign cells and molecules they encounter and
recognize?
A) natural killer cells
B) red blood cells
C) phagocytic cells
D) B cells
5) Which of the following kinds of proteins circulates in the blood and coats the surfaces of
microbes to make them more susceptible to engulfment by phagocytic cells?
A) defensive
B) histamine
C) B cell receptor
D) antigen
6) A major function of natural killer cells is to ________.
A) attack and kill pathogenic microorganisms
B) attack virus-infected cells
C) tag pathogenic microorganisms with antibodies
D) phagocytize microorganisms that have been tagged with antibodies
7) Defensive proteins can assist the immune response by ________.
A) helping viruses reproduce
B) directly destroying pathogens
C) reducing inflammation
D) increasing lymph production
8) A researcher detects an increase in the amount of natural killer cells in a laboratory rat and
concludes that ________.
A) the rat has, or recently had, a viral infection
B) the rat does not have any cancerous tumors
C) the rat’s lymphatic system is not functioning properly
D) the rat’s internal innate defenses are weakened
9) Which of the following is a response of our innate defense system?
A) adaptive immunity
B) inflammation
C) cytotoxic T cell response
D) helper T cell response
10) When you cut yourself, the damaged cells immediately release which of the following
chemical alarm signals?
A) defensive proteins
B) antibodies
C) histamine
D) antihistamines
11) Histamine ________.
A) causes local blood vessels to dilate
B) attracts natural killer cells
C) stimulates the release of defensive proteins
D) repels phagocytic cells
12) The major result of the inflammatory response is to ________.
A) initiate the production of antibodies
B) disinfect and clean damaged tissues
C) initiate the release of defensive proteins
D) initiate the production of natural killer cells
13) Why do diseases involving widespread infection often result in a fever?
A) The inflammatory and immune responses result in extra heat production.
B) The microorganisms trick the brain’s temperature control center into creating a hot
environment that favors their growth.
C) The brain’s temperature control center responds to inflammation by creating a hot
environment unfavorable to the growth of microorganisms.
D) The inflammatory response result is less heat production.
14) A role of the lymphatic system is to ________.
A) transport histamine
B) produce hormones related to fighting infections
C) produce white blood cells
D) return tissue fluid to the circulatory system
15) A person’s spleen may be removed (splenectomy) if it becomes enlarged due to certain types
of cancer, traumatic injury, or damage. What part of the immune system will be most affected by
a splenectomy?
A) internal innate immunity
B) external innate immunity
C) adaptive immunity
D) lymphatic system
16) Antibodies are ________.
A) composed of four fatty acid chains
B) a type of lymphocyte
C) proteins with short carbohydrates attached
D) proteins consisting of four polypeptide chains
17) A substance that can elicit an immune response from a lymphocyte is called a(n) ________.
A) defensive protein
B) pathogen
C) antibody
D) antigen
18) If a person had the thymus gland removed, which of the following would NOT occur in his
or her body?
A) production of B cells
B) production of T cells
C) maturation of B cells
D) maturation of T cells
19) Which statement about antigen recognition in B and T cells is TRUE?
A) B cell antigen receptors can bind to intact freely circulating antigens that are bound to self
proteins.
B) T cell antigen receptors can bind to intact antigens that are bound to self proteins.
C) B cell antigen receptors can bind to intact antigens that are on pathogen surfaces.
D) T cell antigen receptors can bind to intact freely circulating antigens.
20) One kind of vaccine consists of a solution containing ________.
A) antibodies
B) horse serum
C) B cells
D) a harmless variant of a disease-causing microbe
21) Which of the following cell types are specifically responsible for the B cell response?
A) T cells
B) B cells
C) phagocytic cells
D) natural killer cells
22) Which of the following cell types are specifically responsible for the cytotoxic T cell
response?
A) T cells
B) B cells
C) natural killer cells
D) phagocytic cells
23) The immune system is capable of mounting specific responses to particular microorganisms
because ________.
A) lymphocytes are able to change their antigen specificity as required to fight infection
B) the body is able to determine which type of B and T cells to make
C) the body contains an enormous diversity of B and T cells, each with a specific kind of antigen
receptor
D) the body is able to make different antigen receptors depending on the invading
microorganism
24) Antibodies ________.
A) are shaped like the letter B
B) are generalists in that any antibody can bind to any antigen
C) assist in destroying particular antigens
D) are produced by T cells
25) One function of antibodies is to ________.
A) deactivate defensive proteins
B) stimulate the production of antigens
C) phagocytose invading bacteria
D) clump invader cells
26) When in its life cycle does a B cell first exhibit its particular surface antigen receptor?
A) after the memory cell giving rise to it divides
B) before it ever encounters an antigen
C) after it encounters several antigens
D) after it encounters a single antigen
27) When a B or T cell is primed by an interaction with its particular antigen, the cell ________.
A) dies, killing the antigen
B) engulfs the antigen and destroys it
C) grows, divides, and develops further
D) sticks to other cells with attached antigens to form a large clot
28) A primary immune response is the ________.
A) production of primary-type antibodies in the first day of exposure to a microorganism
B) immune response elicited by the second exposure of lymphocytes to a particular antigen
C) immune response elicited by the first exposure of lymphocytes to a particular antigen
D) immune response elicited by the first exposure of memory cells to a particular antigen
29) The primary immune response ________.
A) results in the production of short-lived effector cells via clonal selection
B) results in the production of short-lived memory cells via clonal selection
C) peaks about 2 days after first exposure
D) triggers the secondary immune response
30) Which of the following cell types initiates a secondary immune response?
A) natural killer cells
B) memory cells
C) effector cells
D) plasma cells
31) The secondary response in the B cell response occurs when memory cells bind to ________.
A) antibodies
B) antigens
C) histamine
D) defensive proteins
32) A secondary immune response differs from a primary immune response in that the secondary
response ________.
A) produces helper T cells
B) produces cytotoxic T cells
C) produces effector cells
D) produces memory cells
33) The basic function of cytotoxic T cells is to identify and destroy invaders in our ________.
A) blood or lymph
B) interstitial fluid
C) cells
D) immune system
34) Strep throat can develop from an infection by the bacterium Streptococcus pyogenes. After
infection by this bacterium, cells in the body will respond by producing antibodies against the
bacterium and the toxins it produces. What type of immune response is being described in this
situation?
A) cytotoxic T cell response
B) helper T cell response
C) B cell response
D) inflammation
35) ________ may destroy infected body cells.
A) Phagocytic cells
B) Helper T cells
C) Natural killer cells
D) Cytotoxic T cells
36) Which of the following compounds do mast cells produce?
A) defensive proteins
B) antihistamines
C) histamine
D) antibodies
37) Anaphylactic shock ________.
A) occurs when blood vessels constrict abruptly
B) is a symptom of an immunodeficiency disease
C) causes blood pressure to drop dangerously
D) has no treatment
38) It is best to receive an organ transplant from a donor who ________.
A) looks like you
B) rarely consumes alcohol
C) does not have any allergies
D) best matches your self proteins
39) When the immune system improperly turns against the body’s own molecules, the result is
________.
A) an allergy
B) AIDS
C) an autoimmune disease
D) an immunodeficiency disease