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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
69) A bone marrow transplant may not be appropriate from a given donor (Jane) to a given recipient
(Jane’s cousin Bob), even though Jane has previously given blood for one of Bob’s needed transfusions,
because
A) even though Jane’s blood type is a match to Bob’s, her MHC proteins may not be a match.
B) a blood type match is less stringent than a match required for transplant because blood is more
tolerant of change.
C) for each gene, there is only one blood allele but many tissue alleles.
D) Jane’s class II genes are not expressed in bone marrow.
E) Bob’s immune response has been made inadequate before he receives the transplant.
70) Infection with HIV typically
A) increases the level of helper T cells for the first year after infection.
B) eliminates all T cells immediately.
C) leads to an immediate decrease in the number of HIV in the blood.
D) alters mitochondrial but not genomic DNA sequences.
E) is found in B cells but not in T cells.
71) The transfusion of type A blood to a person who has type O blood would result in
A) the recipient’s B antigens reacting with the donated anti-B antibodies.
B) the recipient’s anti-A antibodies clumping the donated red blood cells.
C) the recipient’s anti-A and anti-O antibodies reacting with the donated red blood cells if the donor was
a heterozygote (Ai) for blood type.
D) no reaction because type O is a universal donor.
E) no reaction because the O-type individual does not have antibodies.
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.
73) In the human disease known as lupus, there is an immune reaction against a patient’s own DNA from
broken or dying cells, which categorizes lupus as
A) an allergy.
B) an immunodeficiency.
C) an autoimmune disease.
D) an antigenic variation.
E) a cancer.
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.
75) An example of a pathogen that undergoes rapid changes resulting in antigenic variation is
A) the influenza virus, which expresses alternative envelope proteins.
B) the strep bacteria, which can be communicated from patient to patient with high efficiency.
C) human papilloma virus, which can remain latent for several years.
D) the causative agent of the autoimmune disease known as rheumatoid arthritis.
E) multiple sclerosis, which attacks the myelinated cells of the nervous system.
76) The ability of some viruses to remain inactive (latent) for a period of time is exemplified by
A) influenza, a particular strain of which returns every 10-20 years.
B) herpes simplex viruses (oral or genital) whose reproduction is triggered by physiological or
emotional stress in the host.
C) Kaposi’s sarcoma, which causes a skin cancer in people with AIDS, but rarely in those not infected
by HIV.
D) the virus that causes a form of the common cold, which recurs in patients many times in their lives.
E) myasthenia gravis, an autoimmune disease that blocks muscle contraction from time to time.
77) Most newly emerging diseases result in
A) greater severity as there are more and more occurrences of the infection.
B) major pandemics, spreading the infection far and wide in the population.
C) the waning of the disease, due to evolutionary selection for resistant hosts and milder pathogens.
D) a destruction of the host’s immune system and eventual cancer.
E) no discoverable relationship with other pathogens in the same or related species.
78) Preventing the appearance of the symptoms of an allergy attack would be the likely result of
A) blocking the attachment of the IgE antibodies to the mast cells.
B) blocking the antigenic determinants of the IgM antibodies.
C) reducing the number of helper T cells in the body.
D) reducing the number of cytotoxic cells.
E) reducing the number of natural killer cells.
79) A patient complaining of watery, itchy eyes and sneezing after being given a flower bouquet as a
birthday gift should first be treated with
A) a vaccine.
B) complement.
C) sterile pollen.
D) antihistamines.
E) monoclonal antibodies.
80) A patient who has a parasitic worm infection and another patient responding to an allergen such as
ragweed pollen have which of the following in common?
A) an increase in cytotoxic T cell number
B) suffering from anaphylactic shock
C) risking development of an autoimmune disease
D) suffering from a decreased level of innate immunity
E) an increase in the levels of IgE
Art Questions
Mutant fruit flies that make only one antimicrobial peptide were tested for survival after infection with
Neurospora crassa fungi or with Micrococcus luteus bacteria.
81) The results shown in the graphs support the hypothesis that
A) adding the defensin gene to such mutants protects them from fungal infection.
B) adding the drosomycin gene to such mutants protects them from fungal infection.
C) wild-type flies with the full set of genes for antimicrobial peptides are highly susceptible to these
infective agents.
D) the presence of any single antimicrobial peptide protects against both infective agents.
E) even the wild-type flies rarely, if ever, survive for five days.
82) According to the graph, naive B cells will produce effector cells
A) between 0 and 7 days.
B) between 7 and 14 days.
C) between 28 and 35 days.
D) between 0 and 7 days and between 7 and 14 days.
E) between 0 and 7 days and between 28 and 35 days.
83) According to the graph, naive memory cells will be produced
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 between 0 and 7 days and between 28 and 35 days.
84) According to the graph, antibodies will be produced
A) between 3 and 7 days.
B) between 14 and 21 days.
C) between 28 and 35 days.
D) between 14 and 21 days and between 42 and 56 days.
E) both between 3 and 7 days and between 28 and 35 days.
85) Study the table. The mother could exhibit an anti-Rh-factor reaction to the developing fetus in
A) Case 1 only.
B) Case 3 only.
C) Cases 1 and 2 only.
D) Cases 1, 2, and 3.
E) It cannot be determined from the data given.
86) In Cases 1 and 2 in the table, the mothers would be able, if needed, to supply blood to the newborn
even seven to nine months after birth; the same would not be true for Case 3. This is because
A) the fetus in Case 3 would provoke an immune response in the mother that would carry over after the
birth.
B) the newborn in Case 3 would soon be able to make antibodies to the B antigen of the mother.
C) newborn children, until about age 2, do not make appreciable antibodies, except against Rh+ antigen.
D) passive immunity would have worn off for the third newborn, but not for the other two.
E) this difference is based on which of the mothers has been nursing her children, not on blood antigens.
87) Study the table. Giving the mother anti-Rh antibodies before delivering her baby would be a wise
precaution in
A) Case 1 only.
B) Case 3 only.
C) Cases 1 and 2 only.
D) Cases 1, 2, and 3.
E) It cannot be determined from the data given.
88) After a long and cold winter, Jim was excited to start exploring the woods behind his new home. His
first adventure included exposure to poison ivy without any reaction. A month later, though, a second
walk through the woods was not so great, since two days later Jim had a terrible rash that lasted for
weeks. The fact that the rash took two days to develop indicates that this immune response was an
example of
A) humoral immunity.
B) cell-mediated immunity.
C) innate immunity.
D) the activation of Toll-like receptors.
E) the activation of the complement system.
Scenario Questions
Use the following information to answer the next few questions.
An otherwise healthy student in your class is infected with EBV, the virus that causes infectious
mononucleosis. The same student had already been infected when she was a child, at which time she had
merely experienced a mild sore throat and swollen lymph nodes in her neck. This time, though infected,
she does not get sick.
89) Her immune system’s recognition of the second infection involves the
A) helper T cells.
B) memory B cells.
C) plasma cells.
D) cytotoxic T cells.
E) natural killer cells.
90) The EBV antigen fragments will be presented by the virus-infected cells along with
A) complement.
B) antibodies.
C) class I MHC molecules.
D) class II MHC molecules.
E) dendritic cells.
Use the following information as background for the next few questions.
Immunodeficiencies can be genetic in origin, and two examples are Bruton’s agammaglobulinemia, an
X-linked disorder, and DiGeorge syndrome, caused by a deletion from chromosome 22. Bruton’s
disorder results in underdeveloped B cells, whereas DiGeorge syndrome results in a missing or seriously
underdeveloped thymus.
91) Select the description that likely indicates a child with Bruton’s disease.
A) baby girl Denise, with low level of antibody response to streptococcal infection
B) baby boy John, with immature T cells, missing CD4 receptors
C) baby boy Jeff, with no plasma cells following infection by bacterial pneumonia
D) baby girl Susan, with no evidence of a thymus gland
E) baby boy Matt, with very low circulating antigens
92) Bruton’s disorder will likely include
A) the failure of heavy-chain gene rearrangement in B cells.
B) the failure to incorporate CD4 receptors into cell membranes.
C) an underexpression of the gene for the β chain of the T cell receptor.
D) an underexpression of the gene for the CD8 receptor molecule.
E) the inability of the bone marrow cells to interact with MHC molecules.
93) Assume that a DGS-like phenotype was produced in a specific “gene-knockout” mouse, one lacking
expression of HA3, a Hox gene known to be involved in developmental regulation in the mouse.
The phenotype of the HA3 knockout can be ascertained by
A) a bone marrow biopsy.
B) an assay for environmental agents known to cause birth defects.
C) a chest X-ray.
D) the measurement of the proportion of CD4 cells to total lymphocytes.
E) an autopsy examination of the adrenal glands.
End-of-Chapter Questions
The following questions are from the end-of–chapter “Test Your Understanding” section in Chapter 43
of the textbook.
94) Which of these is not part of insect immunity?
A) enzyme activation of microbe-killing chemicals
B) activation of natural killer cells
C) phagocytosis by hemocytes
D) production of antimicrobial peptides
E) a protective exoskeleton
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
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.
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.
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
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.
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