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
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
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
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
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
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
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
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
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
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
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
12) Cave art by early humans recognized the existence of
the major signs of inflammation. The most inclusive set of symptoms of
inflammation that might appear in such early human art is
A) heat, pain, and redness.
B) pain and whitening of the surrounding tissue.
C) swelling and pain.
D) antibody-producing cells.
E) swelling, heat, redness, and pain.
Answer: E
13) Ancient peoples sought to identify the indicators of
inflammation because
A) seeing such signs would be cause for their seeking out
a healer in their community.
B) the presence of the signs of inflammation in a patient
could be a condemnation of the healer.
C) the ancients probably knew of plant derivatives that
could reduce the pain of inflammation.
D) the presence of these signs suggests that healing was
taking place; otherwise, the patient would likely die.
E) the signs of inflammation served as a caution to keep
people away from the patient.
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
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
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
17) An invertebrate, such as an insect, has innate
immunity activity in its intestine that likely includes
A) complement.
B) lysozyme.
C) mucus.
D) neutrophils.
E) dendritic cells.
Answer: B
18) In some insects, such as Drosophila, fungal cell wall
elements can activate the protein Toll, which
A) acts as a receptor that, when activated, signals
synthesis of antimicrobial peptides.
B) functions directly to attack the fungi presented to
it.
C) produces antimicrobial peptides by interaction with
chitin.
D) secretes special recognition signal molecules that
identify specific pathogens.
E) causes some hemocytes to phagocytize the pathogens.
Answer: A
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
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
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
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
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
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
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
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
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
33) Clonal selection implies that
A) brothers and sisters have similar immune responses.
B) antigens increase mitosis in specific lymphocytes.
C) only certain cells can produce interferon.
D) a B cell has multiple types of antigen receptors.
E) the body selects which antigens it will respond to.
Answer: B
34) Clonal selection is an explanation for how
A) a single type of stem cell can produce both red blood
cells and white blood cells.
B) V, J, and C gene segments are rearranged.
C) an antigen can provoke production of high levels of
specific antibodies.
D) HIV can disrupt the immune system.
E) macrophages can recognize specific T cells and B cells.
Answer: C
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
56) Normal immune responses can be described as
polyclonal because
A) blood contains many different antibodies and antigens.
B) construction of a hybridoma requires multiple types of
cells.
C) multiple immunoglobulins are produced from descendants
of a single B cell.
D) diverse antibodies are produced for different epitopes
of a specific antigen.
E) macrophages, T cells, and B cells all are involved in
a normal immune response.
Answer: D
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
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
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
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
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
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
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
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
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
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
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.
Answer: A
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.
Answer: A
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.
Answer: B
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
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.
Answer: C
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
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.
Answer: A
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.
Answer: B
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.
Answer: C
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.
Answer: A
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.
Answer: D
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
Answer: E
81
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.
Answer: B
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.
Answer: A
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.
Answer: E
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.
Answer: E
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.
Answer: A
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.
Answer: B
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.
Answer: A
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.
Answer: B
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.
Answer: D
90. 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.
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.
Answer: C
91. 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.
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
Answer: C
92. 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.
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.
Answer: A
93 . 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.
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.
Answer: D
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
Answer: B
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
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
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
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
