Test 4 Final 6

Front 1

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.

Back 1

B) herpes simplex viruses (oral or genital) whose reproduction is triggered by physiological or emotional stress in the host.

Front 2

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.

Back 2

C) the waning of the disease, due to evolutionary selection for resistant hosts and milder pathogens.

Front 3

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.

Back 3

A) blocking the attachment of the IgE antibodies to the mast cells.

Front 4

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.

Back 4

D) antihistamines.

Front 5

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

Back 5

E) an increase in the levels of IgE

Front 6

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.

Back 6

B) adding the drosomycin gene to such mutants protects them from fungal infection.

Front 7

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.

Back 7

A) between 0 and 7 days.

Front 8

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.

Back 8

E) both between 0 and 7 days and between 28 and 35 days.

Front 9

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.

Back 9

E) both between 3 and 7 days and between 28 and 35 days.

Front 10

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.

Back 10

A) Case 1 only.

Front 11

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.

Back 11

B) the newborn in Case 3 would soon be able to make antibodies to the B antigen of the mother.

Front 12

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

Back 12

A) Case 1 only.

Front 13

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.

Back 13

B) cell-mediated immunity.

Front 14

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.

Back 14

D) cytotoxic T cells.

Front 15

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.

Back 15

C) class I MHC molecules.

Front 16

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

Back 16

C) baby boy Jeff, with no plasma cells following infection by bacterial pneumonia

Front 17

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.

Back 17

A) the failure of heavy-chain gene rearrangement in B cells.

Front 18

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.

Back 18

D) the measurement of the proportion of CD4 cells to total lymphocytes.

Front 19

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

Back 19

B) activation of natural killer cells

Front 20

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

Back 20

C) variable regions of a heavy chain and light chain combined

Front 21

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

Back 21

C) B cells secrete antibodies against a pathogen; cytotoxic T cells kill pathogen-infected host cells.

Front 22

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.

Back 22

D) A lymphocyte has receptors for multiple different antigens.

Front 23

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

Back 23

B) the set of MHC molecules produced

Front 24

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

Back 24

B) lymphocytes with receptors that can bind to the pathogen.

Front 25

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

Back 25

C) producing proteins very similar to those of other viruses