Chapter 43
1) Innate immunity A) is activated immediately upon infection. B) depends on a newly infected animal's previous exposure to the same pathogen. C) is based on recognition of antigens that are specific to different pathogens. D) is found only in vertebrate animals. E) utilizes highly specific antigen receptors on B cells.
Answer: A
11) Antihistamine treatment reduces A) blood vessel dilation. B) phagocytosis of antigens. C) MHC presentation by macrophages. D) the secondary immune response. E) clonal selection by antigens.
Answer: A
21) Septic shock, a systemic response including high fever and low blood pressure, is a response to A) certain bacterial infections. B) specific forms of viruses. C) the presence of natural killer cells. D) a fever of >103°F in adults. E) increased production of neutrophils.
Answer: A
24) Bacterial infection in a previously uninfected house cat would most quickly activate its A) Toll-like receptors that bind to lipopolysaccharides. B) memory cells to produce antibodies. C) plasma cells to produce antigens. D) cytotoxic T cells. E) humoral immune responses.
Answer: A
35) Secondary immune responses upon a second exposure to a pathogen are due to the activation of A) memory cells. B) macrophages. C) stem cells. D) B cells. E) T cells.
Answer: A
36) The MHC is important in a T cell's ability to A) distinguish self from nonself. B) recognize specific parasitic pathogens. C) identify specific bacterial pathogens. D) identify specific viruses. E) recognize differences among types of cancer.
Answer: A
38) The activation of helper T cells is likely A) when an antigen is displayed by a dendritic cell. B) when a cytotoxic T cell releases cytokines. C) when natural killer (NK) cells come in contact with a tumor cell. D) in the bone marrow during the self-tolerance test. E) when B cells respond to T-independent antigens.
Answer: A
39) An immunoglobulin (Ig) molecule, of whatever class, with regions symbolized as C or V, H or L, has a light chain made up of A) one C region and one V region. B) three C regions and one V region. C) one H region and one L region. D) three H regions and one L region. E) two C regions and two V regions.
Answer: A
45) The cell-mediated immunity that destroys virally infected cells involves A) cytotoxic T cells. B) natural killer cells. C) helper T cells. D) macrophages. E) B cells.
Answer: A
46) Which of the following cells are involved in cell-mediated immunity and also respond to class I MHC molecule-antigen complexes? A) cytotoxic T cells B) natural killer cells C) helper T cells D) macrophages E) B cells
Answer: A
5) The lymphatic fluid A) is a filtrate of the blood, as is urine. B) is completely separate from the circulatory system for blood. C) carries both red and white blood cells. D) functions in adaptive immunity but not in innate immunity. E) carries a toxic gas that kills cancerous cells.
Answer: A
58) When antibodies bind antigens, the clumping of antigens results from A) the multivalence of the antibody having at least two binding regions. B) disulfide bridges between the antigens. C) complement that makes the affected cells sticky. D) bonds between class I and class II MHC molecules. E) denaturation of the antibodies.
Answer: A
65) For the successful development of a vaccine to be used against a pathogen, it is necessary that A) the surface antigens of the pathogen not change. B) a rearrangement of the B cell receptor antibodies takes place. C) all of the surface antigens on the pathogen be identified. D) the pathogen has only one epitope. E) the MHC molecules are heterozygous.
Answer: A
72) An immune response to a tissue graft will differ from an immune response to a bacterium because A) MHC molecules of the donor may stimulate rejection of the graft tissue, but bacteria lack MHC molecules. B) the tissue graft, unlike the bacterium, is isolated from the circulation and will not enter into an immune response. C) a response to the graft will involve B cells and a response to the bacterium will not. D) a bacterium cannot escape the immune system by replicating inside normal body cells. E) the graft will stimulate an autoimmune response in the recipient.
Answer: A
9) Salmonella bacterial poisoning can be initiated when A) the microbe survives the acidic environment of the stomach and resists lysosomal degradation in macrophages. B) the chemotactic messengers released by the microbe do not attract sufficient neutrophils to entirely destroy the infection. C) there is a delay in selection of the population of eosinophils that recognize and fight these microbes. D) the microbes release chemical messengers that make them resistant to phagocytosis. E) The combination of foods eaten at the meal reduces the pH of the stomach sufficiently so that ingested microbes are not destroyed.
Answer: A
For the questions below, match the following answers with the phrase that best describes them. Each answer may be used once, more than once, or not at all. A) cytotoxic T cells B) delayed sensitivity T cells C ) helper T cells D) suppressor T cells E) B cells release perforin, which causes target cells to lose their cytoplasm
Answer: A
The T in T lymphocytes stands for A) thymus. B) thyroid C) toxic. D) trigger. E) threshold.
Answer: A
What attracts helper T cells to macrophages? A) interleukins B) lymphotoxins C) antigens D) interferons E) antibodies
Answer: A
Which of the following defensive actions would be part of the body's third, or most advanced, line of defense? A) antibody production by plasma cells B) action of natural killer cells C) lysozyme production D) histamine release by basophils E) phagocytosis by neutrophils
Answer: A
Which of the following is an example of positive feedback in the immune system? A) Cells release a cytokine that stimulates these cells to divide and release more of the cytokine. B) Memory cells proliferate and produce antibodies. C) Cytotoxic cells release substances that attract macrophages. D) Large antigens with many repeating antigenic determinant sites can stimulate B cells without the aid of T cells. E) Both A and B are examples of positive feedback in the immune system.
Answer: A
15) Inflammatory responses typically include A) clotting proteins migrating away from the site of infection. B) increased activity of phagocytes in an inflamed area. C) reduced permeability of blood vessels to conserve plasma. D) release of substances to decrease the blood supply to an inflamed area. E) inhibiting the release of white blood cells from bone marrow.
Answer: B
22) Infection by a bacterium that has elements on its surface that enhance its resistance to lysozyme will likely result in A) destruction of the bacterium by NK cells. B) successful reproduction of the bacterium and continued progression of the disease. C) removal of the bacterium by dendritic cells and its concentration in lymph nodes. D) the infected individual's humoral immunity becoming the only route of infection response. E) lymphocytes migrating from the thymus to attack the bacterium.
Answer: B
23) Adaptive immunity depends on A) traits common to groups of pathogens. B) pathogen-specific recognition. C) maternal provision of antibodies to offspring. D) plants being exposed to new pathogens. E) having exhausted all options for innate immunity responses.
Answer: B
25) A key part of the humoral immune response is A) the attack of cytotoxic T cells on infected host cells. B) the production of antibodies by plasma cells. C) perforation of infected host cells by perforin. D) the attack of phagocytes on living pathogens. E) the initiation of programmed cell death in infected host cells.
Answer: B
26) The receptors on T cells and B cells bind to A) antibodies. B) antigens. C) natural killer cells. D) double-stranded RNA. E) immunoglobulins.
Answer: B
47) The cells involved in innate immunity, whose absence increases the chances of developing malignant tumors, are A) cytotoxic T cells. B) natural killer cells. C) helper T cells. D) macrophages. E) B cells.
Answer: B
48) Select the pathway that would lead to the activation of cytotoxic T cells. A) B cell contact antigen → helper T cell is activated → clonal selection occurs B) body cell becomes infected with a virus → new viral proteins appear → class I MHC molecule-antigen complex displayed on cell surface C) self-tolerance of immune cells → B cells contact antigen → cytokines released D) complement is secreted → B cell contacts antigen → helper T cell activated → cytokines released E) cytotoxic T cells → class II MHC molecule-antigen complex displayed → cytokines released → cell lysis
Answer: B
54) T cells of the immune system include A) CD4, CD8, and plasma cells. B) cytotoxic and helper cells. C) plasma, antigen-presenting, and memory cells. D) lymphocytes, macrophages, and dendritic cells. E) class I MHC, class II MHC, and memory cells.
Answer: B
57) Antibodies of the different classes IgM, IgG, IgA, IgD, and IgE differ from each other A) in the way they are produced. B) in their heavy-chain structure. C) in the type of cell that produces them. D) by the antigenic determinants that they recognize. E) by the number of carbohydrate subunits they have.
Answer: B
64) An individual who has been bitten by a poisonous snake that has a fast-acting toxin would likely benefit from A) vaccination with a weakened form of the toxin. B) injection of antibodies to the toxin. C) injection of interleukin-1. D) injection of interleukin-2. E) injection of interferon.
Answer: B
98) Which of the following should be the same in identical twins? A) the set of antibodies produced B) the set of MHC molecules produced C) the set of T cell antigen receptors produced D) the susceptibility to a particular virus E) the set of immune cells eliminated as self-reactive
Answer: B
99) Vaccination increases the number of A) different receptors that recognize a pathogen. B) lymphocytes with receptors that can bind to the pathogen. C) epitopes that the immune system can recognize. D) macrophages specific for a pathogen. E) MHC molecules that can present an antigen.
Answer: B
A patient can produce antibodies against some bacterial pathogens, but he does not produce antibodies against viral infections. This is probably due to a disorder in which cells of the immune system? A) B cells B) T cells C) plasma cells D) cytotoxic cells E) macrophages
Answer: B
After preparing barbequed chicken, you came down with salmonella poisoning. Why? A) The bacterium released chemical messengers that make it resistant to phagocytosis. B) The microbe survived the acidic environment of the stomach and resisted lysosomal degradation in macrophages. C) The combination of foods eaten at the meal reduced the pH of the stomach sufficiently that the bacterium was not destroyed. D) The chemotactic messengers released by the salmonella bacterium did not attract sufficient neutrophils to entirely destroy the infection. E) There was a delay in selection of the population of eosinophils that recognize and are responsible for fighting these bacterial infections.
Answer: B
All of the following statements about antibodies are true except: A) The structure of antibodies includes both a constant and a variable region. B) Antibodies bind with foreign cells and destroy them. C) Antibodies act as signals to blood complement proteins or phagocytes. D) Antibodies are immunoglobulin proteins. E) Plasma B cells are responsible for the production of antibodies.
Answer: B
All of the following statements about lymphocytes are true except: A) All cells are produced in bone marrow. B) They are contained only within the lymphatic vessels and nodes. C) All cells differentiate only from pluripotent stem cells. D) They originate from the liver of a developing fetus. E) They may mature in either bone marrow or the thymus gland
Answer: B
Each of the items below is a response of helper T cells once they are stimulated except A) releasing interleukin-2. B) releasing interleukin-1. C) enlarging in size. D) producing memory cells. E) dividing by mitosis.
Answer: B
Inflammatory responses may include all of the following except A) release of substances to increase the blood supply to an inflamed area. B) reduced permeability of blood vessels to conserve plasma. C) The combination of foods eaten at the meal reduced the pH of the stomach sufficiently that the bacterium was not destroyed. D) The chemotactic messengers released by the salmonella bacterium did not attract sufficient neutrophils to entirely destroy the infection. E) There was a delay in selection of the population of eosinophils that recognize and are responsible for fighting these bacterial infections.
Answer: B
The next questions refer to the following substances. blood complement proteins interleukin-1 interleukin-2 antibodies perforin Which substance is secreted by antigen-presenting cells? A) 1 B) 2 C) 3 D) 4 E) 5
Answer: B
The next questions refer to the following substances. blood complement proteins interleukin-1 interleukin-2 antibodies perforin Which substance(s) activate(s) T cells? A) 1 and 4 B) 2 and 3 C) 3 only D) 1 only E) 5 only
Answer: B
The next questions refer to the following substances. blood complement proteins interleukin-1 interleukin-2 antibodies perforin Which substances are used in the immune system to kill targeted, infected cells? A) 2 and 3 B) 1 and 5 C) 1 and 4 D) 4 and 5 E) 1, 4, and 5
Answer: B
The questions below refer to the following list. Match the term that best fits each of the following descriptions. Each term may be used once, more than once, or not at all. a.clonal selection b.opsonization c.complement system d. passive immunity e. vaccination coating of foreign cells by proteins to attract macrophages
Answer: B
What is complement? A) a hormone from the thymus B) a group of proteins C) a specialized white blood cell D) a form of interferon E) a set of antigens
Answer: B
When would B cells produce effector cells? A) between 28 and 35 days B) between 0 and 7 days C) between 7 and 14 days D) Both A and B are correct. E) Both A and C are correct.
Answer: B
Which of the following cell types is responsible for initiating a secondary immune response? A) stem cells B) memory cells C) macrophages D) B cells E) T cells
Answer: B
100) Which of the following would not help a virus avoid triggering an adaptive immune response? A) having frequent mutations in genes for surface proteins B) infecting cells that produce very few MHC molecules C) producing proteins very similar to those of other viruses D) infecting and killing helper T cells E) building the viral shell from host proteins
Answer: C
19) Mammals have Toll-like receptors (TLRs) that can recognize a kind of macromolecule that is absent from vertebrates but present in/on certain groups of pathogens, including viral A) lipopolysaccharides. B) double-stranded DNA. C) double-stranded RNA. D) glycoproteins. E) phospholipids.
Answer: C
40) The ability of one person to produce over a million different antibody molecules does not require over a million different genes; rather, this wide range of antibody production is due to A) alternative splicing of exons after transcription. B) increased rate of mutation in the RNA molecules. C) DNA rearrangements. D) rearrangements of cytosolic proteins in the thymus cells. E) crossing over between the light and heavy chains of each antibody molecule during meiosis I.
Answer: C
43) This type of immunity is present only when a newborn infant is being fed by actively nursing on its mother and ends when nursing ends. A) innate immunity B) active immunity C) passive immunity D) cell-mediated immunity E) adaptive immunity
Answer: C
49) Among the last line of defenses against prolonged exposure to an extracellular pathogen is A) lysozyme production. B) phagocytosis by neutrophils. C) antibody production by plasma cells. D) histamine release by basophils. E) lysis by natural killer cells.
Answer: C
6) An inflammation-causing signal released by mast cells at the site of an infection is A) an interferon. B) lymphatic fluid. C) histamine. D) mucus. E) sodium ions.
Answer: C
61) Naturally acquired passive immunity results from the A) injection of vaccine. B) ingestion of interferon. C) placental transfer of antibodies. D) absorption of pathogens through mucous membranes. E) injection of antibodies.
Answer: C
68) The number of MHC protein combinations possible in a given population is enormous. However, an individual in that diverse population has a far more limited array of MHC molecules because A) the MHC proteins are made from several different gene regions that are capable of rearranging in a number of ways. B) MHC proteins from one individual can only be of class I or class II. C) each of the MHC genes has a large number of alleles, but each individual only inherits two for each gene. D) once a B cell has matured in the bone marrow, it is limited to two MHC response categories. E) once a T cell has matured in the thymus, it can only respond to two MHC categories.
Answer: C
7) A systemic inflammatory response that is often life-threatening is A) mild fever. B) aches and dull pain. C) septic shock. D) high blood pressure. E) increased white blood cell count.
Answer: C
95) An epitope associates with which part of an antigen receptor or antibody? A) the disulfide bridge B) the heavy-chain constant regions only C) variable regions of a heavy chain and light chain combined D) the light-chain constant regions only E) the tail
Answer: C
96) Which statement best describes the difference in responses of effector B cells (plasma cells) and cytotoxic T cells? A) B cells confer active immunity; cytotoxic T cells confer passive immunity. B) B cells kill pathogens directly; cytotoxic T cells kill host cells. C) B cells secrete antibodies against a pathogen; cytotoxic T cells kill pathogen-infected host cells. D) B cells carry out the cell-mediated response; cytotoxic T cells carry out the humoral response. E) B cells respond the first time a pathogen is present; cytotoxic T cells respond subsequent times.
Answer: C
A major difference between active and passive immunity is that active immunity requires A) secretion of interleukins from macrophages. B) acquisition and activation of antibodies. C) direct exposure to a living or simulated disease organism. D) transfer of antibodies from the mother across the placenta. E) proliferation of lymphocytes in bone marrow.
Answer: C
Cell-mediated immunity is mostly the function of A) B cells. B) complement cells. C) T cells. D) cytotoxic cells. E) erythrocytes
Answer: C
For the questions below, match the following answers with the phrase that best describes them. Each answer may be used once, more than once, or not at all. A) cytotoxic T cells B) delayed sensitivity T cells C ) helper T cells D) suppressor T cells E) B cells cooperate with macrophages to enable the production of antibodies by effector cells
Answer: C
For the questions below, match the following answers with the phrase that best describes them. Each answer may be used once, more than once, or not at all. A) cytotoxic T cells B) delayed sensitivity T cells C ) helper T cells D) suppressor T cells E) B cells release cytokines, which activate B cells
Answer: C
Jenner successfully used cowpox virus as a vaccine against a different virus that causes smallpox. Why was he successful even though he used viruses of different kinds? A) There are some antigenic determinants common to both pox viruses. B) Cowpox and smallpox are antibodies with similar immunizing properties. C) The cowpox virus made antibodies in response to the presence of smallpox. D) The immune system responds nonspecifically to antigens. E) All of the below are true.
Answer: C
The questions below refer to the following list. Match the term that best fits each of the following descriptions. Each term may be used once, more than once, or not at all. a. clonal selection b. opsonization c. complement system d. passive immunity e. vaccination part of both specific and nonspecific defense
Answer: C
Which of the following would be most beneficial in treating an individual who has been bitten by a poisonous snake that has a fast-acting toxin? A) injection of interferon B) vaccination with a weakened form of the toxin C) injection of antibodies to the toxin D) injection of interleukin-2 E) injection of interleukin-1
Answer: C
10) The complement system is A) a set of proteins involved in innate but not acquired immunity. B) a set of proteins secreted by cytotoxic T cells and other CD8 cells. C) a group of proteins that includes interferons and interleukins. D) a group of antimicrobial proteins that act together in a cascade fashion. E) a set of proteins that act individually to attack and lyse microbes.
Answer: D
14) The cells and signaling molecules that initiate inflammatory responses are A) the phagocytes and the lysozymes. B) the phagocytes and the chemokines. C) the dendritic cells and the interferons. D) the mast cells and the histamines. E) the lymphocytes and the interferons.
Answer: D
20) Histamines trigger dilation of nearby blood vessels as well as an increase in their permeability, producing A) redness and heat only. B) swelling only. C) pain. D) redness, heat, and swelling. E) all of the signs of a major infection.
Answer: D
27) An epitope is A) part of the interferons that penetrate foreign cells. B) a protein protruding from the surface of B cells. C) two structurally similar antibodies dissolved in the blood plasma. D) that part of an antigen that actually binds to an antigen receptor. E) a mirror image of an antigen.
Answer: D
28) B cells have antigen receptors that bind to antigens that are either freely dissolved or present on the surface of invading/foreign cells. T cells have antigen receptors that A) are active only in lymph nodes. B) bind only to antigens present on the surface of the invading/foreign cells. C) bind only to freely dissolved antigens in the plasma. D) bind to antigens presented on major histocompatability complexes by host cells. E) bind to antigens that are either freely dissolved or present on the surface of invading/foreign cells.
Answer: D
3) A fruit fly, internally infected by a potentially pathogenic fungus, is protected by A) its plasma cells. B) its immunoglobulins. C) its antibodies. D) its antimicrobial peptides. E) its B cells.
Answer: D
31) Antigens are A) proteins found in the blood that cause foreign blood cells to clump. B) proteins embedded in B cell membranes. C) proteins that consist of two light and two heavy polypeptide chains. D) foreign molecules that trigger the generation of antibodies. E) proteins released during an inflammatory response.
Answer: D
32) A newborn who is accidentally given a drug that destroys the thymus would most likely A) lack class I MHC molecules on cell surfaces. B) lack humoral immunity. C) be unable to genetically rearrange antigen receptors. D) be unable to differentiate and mature T cells. E) have a reduced number of B cells and be unable to form antibodies.
Answer: D
37) A patient who can produce antibodies against some bacterial pathogens, but not against viral infections, probably has a disorder in his A) B cells. B) plasma cells. C) natural killer cells. D) T cells. E) macrophages.
Answer: D
4) Engulfing-phagocytic cells of innate immunity include all of the following except A) neutrophils. B) macrophages. C) dendritic cells. D) natural killer cells.
Answer: D
41) Immunological memory accounts for A) the human body's ability to distinguish self from nonself. B) the observation that some strains of the pathogen that causes dengue fever cause worse disease than others. C) the ability of a helper T cell to signal B cells via cytokines. D) the ancient observation that someone who had recovered from the plague could safely care for those newly diseased. E) the ability of the immune system to present antigen fragments in association with MHC antigens.
Answer: D
44) Yearly vaccination of humans for influenza viruses is necessary because A) of an increase in immunodeficiency diseases. B) flu can generate anaphylactic shock. C) surviving the flu one year exhausts the immune system to nonresponsiveness the second year. D) rapid mutation in flu viruses alters the surface proteins in infected host cells. E) flu leads to autoimmune disorders.
Answer: D
53) CD4 and CD8 are A) proteins secreted by antigen-presenting cells. B) receptors present on the surface of natural killer (NK) cells. C) T-independent antigens. D) molecules present on the surface of T cells where they interact with MHC molecules. E) molecules on the surface of antigen-presenting cells where they enhance B cell activity.
Answer: D
59) Phagocytosis of microbes by macrophages is enhanced by A) the binding of antibodies to the surface of microbes. B) antibody-mediated agglutination of microbes. C) the release of cytokines by activated B cells. D) the binding of antibodies to the surface of microbes and antibody-mediated agglutination of microbes only. E) the binding of antibodies to the surface of microbes, antibody-mediated agglutination of microbes, and the release of cytokines by activated B cells.
Answer: D
60) The primary function of humoral immunity is A) to defend against fungi and protozoa. B) to reject transplanted tissues. C) to protect the body against cells that become cancerous. D) to protect the body against extracellular pathogens. E) to defend against bacteria and viruses that have already infected cells.
Answer: D
62) In active immunity, but not passive immunity, there is A) acquisition and activation of antibodies. B) proliferation of lymphocytes in bone marrow. C) the transfer of antibodies from the mother across the placenta. D) the requirement for direct exposure to a living or simulated pathogen. E) the requirement of secretion of interleukins from macrophages.
Answer: D
63) Jenner's successful use of cowpox virus as a vaccine against the smallpox virus is due to the fact that A) the immune system responds nonspecifically to antigens. B) the cowpox virus made antibodies in response to the presence of smallpox. C) cowpox and smallpox are antibodies with similar immunizing properties. D) there are some antigenic determinants common to both pox viruses. E) cowpox and smallpox are caused by the same virus.
Answer: D
66) A diseased patient is exposed to an unknown agent while out of the country. The patient's blood is found to have a high proportion of lymphocytes with CD8 surface proteins in her blood, a likely result of A) the patient having encountered a bacterial infection which elicited CD8+ T cells. B) the disease having been caused by a multicellular parasite, such as can be encountered in polluted water sources. C) the CD8 proteins having been discharged from these lymphocytes to lyse the infected cells. D) a viral infection eliciting proliferation of CD8+ cytotoxic T cells. E) the CD8 proteins having "marked" the surface of cells that accumulate after the infection is over and signal patient recovery.
Answer: D
8) The eyes and the respiratory tract are both protected against infections by A) the mucous membranes that cover their surface. B) the secretion of complement proteins. C) the release of slightly alkaline secretions. D) the secretion of lysozyme onto their surfaces. E) interferons produced by immune cells.
Answer: D
97) Which of the following statements is not true? A) An antibody has more than one antigen-binding site. B) An antigen can have different epitopes. C) A pathogen makes more than one antigen. D) A lymphocyte has receptors for multiple different antigens. E) A liver cell makes one class of MHC molecule.
Answer: D
Each indication below is a clinical characteristic of inflammation except A) increased blood flow. B) edema. C) redness. D) decreased temperature. E) pain.
Answer: D
In mammalian defenses against invading pathogens, all of these are considered nonspecific defense mechanisms except A) antimicrobial proteins. B) mucous membranes. C) the inflammatory response. D) the immune system. E) the skin.
Answer: D
In the inflammatory response, the absence of which of the following would prevent all the others from happening? A) leakage of plasma to the affected area B) increased permeability of blood vessels C) dilation of arterioles D) release of histamine E) increased population of phagocytes in the area
Answer: D
The main effect of histamine is to A) phagocytize pathogens. B) decrease blood flow. C) attract T cells. D) dilate blood vessels. E) destroy white blood cells.
Answer: D
The questions below refer to the following list. Match the term that best fits each of the following descriptions. Each term may be used once, more than once, or not at all. a. clonal selection b. opsonization c. complement system d. passive immunity e. vaccination protection by antibodies that cross the placenta from mother to fetus
Answer: D
What are antigens? A) proteins that consist of two light and two heavy polypeptide chains B) proteins found in the blood that cause foreign blood cells to clump C) proteins embedded in B cell membranes D) antibody-generating foreign macromolecules E) Both A and C are correct.
Answer: D
What are plasma cells? A) cells that produce few antibodies B) the cells that are responsible for the phagocytosis of foreign organisms C) immature forms of T cells D) the effector cells of humoral immunity E) the cells that are responsible for immunological memory
Answer: D
When antibodies attack antigens, clumping of the affected cells generally occurs. This is best explained by A) denaturation of the antibodies. B) bonds between class I and class II MHC molecules. C) disulfide bridges between the antigens. D) the shape of the antibody with at least two binding regions. E) complement that makes the affected cells sticky.
Answer: D
Which of the following are types of T cells that participate in the immune response system? A) interleukin-1, interleukin-2, and interferon B) lymphocytes, macrophages, and coelomocytes C) plasma, antigen-presenting, and memory cells D) cytotoxic and helper cells E) CD4, CD8, and helper cells
Answer: D
Which of the following is not a part of an antibody molecule? A) the heavy chains B) the light chains C) the variable or V regions D) the epitope E) the constant or C regions
Answer: D
Which of the following is true of both T cells and B cells? A) They are produced from stem cells of the bone marrow. B) They produce effector cells against specific pathogens. C) They can attack and destroy invading pathogens. D) Both A and B are true. E) A, B, and C are all true.
Answer: D
Which of the following statements about humoral immunity is correct? A) It primarily defends against bacteria and viruses that have already infected cells. B) It primarily defends against fungi and protozoa. C) It is responsible for transplant tissue rejection. D) It is mounted by lymphocytes that have matured in the bone marrow. E) It protects the body against cells that become cancerous.
Answer: D
Which of the following types of cells is not involved in both antibody-mediated immunity and cell-mediated immunity? A) macrophages B) memory cells C) pathogenic cells D) plasma cells E) helper T cells
Answer: D
16) Bacteria entering the body through a small cut in the skin A) inactivate the erythrocytes. B) stimulate apoptosis of nearby body cells. C) stimulate release of interferons. D) stimulate natural killer cell activity. E) activate a group of proteins called complement.
Answer: E
2) Acidity in human urine is an example of A) cell-mediated immune responses. B) antibody activation. C) acquired immunity. D) adaptive immunity. E) innate immunity.
Answer: E
29) Within a differentiated B cell, the rearrangement of DNA sequences between variable regions and joining regions is accomplished by A) polyadenylase. B) RNA polymerase. C) reverse transcriptase. D) epitopase. E) recombinase.
Answer: E
30) Clonal selection of B cells activated by antigen exposure leads to production of A) large numbers of neutrophils. B) large quantities of the antigen initially recognized. C) vast numbers of B cells with random antigen-recognition receptors. D) long-lived erythrocytes that can later secrete antibodies for the antigen. E) short-lived plasma cells that secrete antibodies for the antigen.
Answer: E
42) The function of antibodies is to A) inject toxins into living pathogens. B) secrete cytokines that attract macrophages to infection sites. C) release perforins to disrupt infected cells. D) act as Toll-like receptors. E) mark pathogenic cells for destruction.
Answer: E
50) Arrange these components of the mammalian immune system as it first responds to a pathogen in the correct sequence. I. Pathogen is destroyed. II. Lymphocytes secrete antibodies. III. Antigenic determinants from pathogen bind to antigen receptors on lymphocytes. IV. Lymphocytes specific to antigenic determinants from pathogen become numerous. V. Only memory cells remain. A) I → III → II → IV → V B) III → II → I → V → IV C) II → I → IV → III → V D) IV → II → III → I → V E) III → IV → II → I → V
Answer: E
51) A cell type that interacts with both the humoral and cell-mediated immune pathways is a A) plasma cell. B) cytotoxic T cell. C) natural killer cell. D) CD8 cell. E) helper T cell.
Answer: E
52) A nonfunctional CD4 protein on a helper T cell would result in the helper T cell being unable to A) respond to T-independent antigens. B) lyse tumor cells. C) stimulate a cytotoxic T cell. D) interact with a class I MHC-antigen complex. E) interact with a class II MHC-antigen complex
Answer: E
55) B cells interacting with helper T cells are stimulated to differentiate when A) B cells produce IgE antibodies. B) B cells release cytokines. C) helper T cells present the class II MHC molecule-antigen complex on their surface. D) helper T cells differentiate into cytotoxic T cells. E) helper T cells release cytokines.
Answer: E
67) The switch of one B cell from producing one class of antibody to another antibody class that is responsive to the same antigen is due to A) mutation in the genes of that B cell, induced by exposure to the antigen. B) the rearrangement of V region genes in that clone of responsive B cells. C) a switch in the kind of antigen-presenting cell that is involved in the immune response. D) a patient's reaction to the first kind of antibody made by the plasma cells. E) the rearrangement of immunoglobulin heavy-chain C region DNA.
Answer: E
74) A patient who undergoes a high level of mast cell degranulation, dilation of blood vessels, and acute drop in blood pressure is likely suffering from A) an autoimmune disease. B) a typical allergy that can be treated by antihistamines. C) an organ transplant, such as a skin graft. D) the effect of exhaustion on the immune system. E) anaphylactic shock immediately following exposure to an allergen.
Answer: E
All of the following are correct statements about nonspecific defenses except: A) They include physical and chemical barriers. B) They may involve the formation of membrane attack complexes. C) Macrophages and natural killer cells are participants in the process. D) They include inflammatory responses. E) They must be primed by the presence of antigen
Answer: E
An alarm substance that triggers an inflammatory reaction is A) pyrogen. B) thyroxine. C) immunoglobulin. D) adrenaline. E) histamine.
Answer: E
For the questions below, match the following answers with the phrase that best describes them. Each answer may be used once, more than once, or not at all. A) cytotoxic T cells B) delayed sensitivity T cells C ) helper T cells D) suppressor T cells E) B cells form plasma cells that give rise to antibodies
Answer: E
If a person's bone marrow were destroyed by radiation, which of the following cells could not be produced? A) T cells B) erythrocytes C) neutrophils D) B cells E) All of the above could not be produced.
Answer: E
Naturally acquired passive immunity would involve the A) absorption of pathogens through mucous membranes. B) injection of vaccine. C) ingestion of interferon. D) injection of antibodies. E) placental transfer of antibodies
Answer: E
Physical barriers to invasion by other organisms A) may work in conjunction with secretions like tears, perspiration, and mucus. B) are difficult for bacteria and viruses to penetrate. C) include the skin and the mucous membranes. D) Only A and C are correct. E) A, B, and C are correct.
Answer: E
Prevention of a disease by the injection of an antiserum containing gamma globulins is an example of A) autoimmunity. B) clonal selection. C) active immunity. D) cell-mediated immunity. E) passive immunity.
Answer: E
The MHC (major histocompatibility complex) is important in A) distinguishing self from nonself. B) identifying bacterial pathogens. C) recognizing parasitic pathogens. D) identifying abnormal cells. E) Both A and D are correct.
Answer: E
The lymphatic system involves which of the following organs? A) appendix and special portions of the small intestine B) adenoids and tonsils C) spleen and lymph nodes D) Only A and B are correct. E) A, B, and C are correct.
Answer: E
The questions below refer to the following list. Match the term that best fits each of the following descriptions. Each term may be used once, more than once, or not at all. a.clonal selection b. opsonization c.complement system d.passive immunity e. vaccination process in which an attenuated pathogen is used to stimulate the body to produce antibodies against the pathogen
Answer: E
What is the single most important event establishing a primary immune response? A) the presentation of viral protein complexed to MHC I B) apoptosis of virally infected cells C) the phagocytosis of microbes by antigen-presenting cells D) the lyses of virally infected cell by cytotoxic T cells E) the recognition of self versus foreign
Answer: E
When would memory cells proliferate? A) between 0 and 7 days B) between 7 and 14 days C) between 28 and 35 days D) between 35 and 42 days E) Both A and C are correct.
Answer: E
Which of the following is (are) not involved in the activation and functioning of cytotoxic T cells? A) perforin B) interleukins C) class I MHC molecules D) antigen-presenting cells E) T cell surface protein CD4
Answer: E
Which of the following participates in both the specific and nonspecific defense systems of the body? A) B cells B) complement C) macrophages D) pyrogens E) Both B and C are correct.
Answer: E
