Test 4 Final 5

Front 1

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.

Back 1

E) helper T cell.

Front 2

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.

Back 2

E) interact with a class II MHC-antigen complex.

Front 3

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

Back 3

D) molecules present on the surface of T cells where they interact with MHC molecules.

Front 4

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

Back 4

B) cytotoxic and helper cells.

Front 5

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.

Back 5

E) helper T cells release cytokines.

Front 6

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.

Back 6

D) diverse antibodies are produced for different epitopes of a specific antigen.

Front 7

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.

Back 7

B) in their heavy-chain structure.

Front 8

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.

Back 8

A) the multivalence of the antibody having at least two binding regions.

Front 9

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.

Back 9

D) the binding of antibodies to the surface of microbes and antibody-mediated agglutination of microbes only.

Front 10

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.

Back 10

D) to protect the body against extracellular pathogens.

Front 11

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.

Back 11

C) placental transfer of antibodies.

Front 12

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.

Back 12

D) the requirement for direct exposure to a living or simulated pathogen.

Front 13

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.

Back 13

D) there are some antigenic determinants common to both pox viruses.

Front 14

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.

Back 14

B) injection of antibodies to the toxin.

Front 15

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.

Back 15

A) the surface antigens of the pathogen not change.

Front 16

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.

Back 16

D) a viral infection eliciting proliferation of CD8+ cytotoxic T cells.

Front 17

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.

Back 17

E) the rearrangement of immunoglobulin heavy-chain C region DNA.

Front 18

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.

Back 18

C) each of the MHC genes has a large number of alleles, but each individual only inherits two for each gene.

Front 19

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.

Back 19

A) even though Jane's blood type is a match to Bob's, her MHC proteins may not be a match.

Front 20

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.

Back 20

A) increases the level of helper T cells for the first year after infection.

Front 21

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.

Back 21

B) the recipient's anti-A antibodies clumping the donated red blood cells.

Front 22

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.

Back 22

A) MHC molecules of the donor may stimulate rejection of the graft tissue, but bacteria lack MHC molecules.

Front 23

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.

Back 23

C) an autoimmune disease.

Front 24

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.

Back 24

E) anaphylactic shock immediately following exposure to an allergen.

Front 25

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.

Back 25

A) the influenza virus, which expresses alternative envelope proteins.