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Bio 347
First Examination
September 28, 2006
Version A
Name_______________________________________________
Note: Please place your name and answers on the scantron provided. We will not give credit for
answers marked on the exam that differ from the scantron--we will grade only the scantron. Hand
in the exam + scantron.
I. Multiple choice (2 points each for a total of 100 points)
1. Grafts between non-related individuals
A. are rejected slowly as a result of minor histocompatibility antigens.
B. are subject to hyperacute rejection.
C. are not rejected, even without immunosuppression.
D. are not rejected if a kidney is grafted, but skin grafts are rejected.
2. Grafts between genetically identical individuals (i.e., identical twins)
A. are rejected slowly as a result of minor histocompatibility antigens.
B. are subject to hyperacute rejection.
C. are not rejected, even without immunosuppression.
D. are not rejected if a kidney is grafted, but skin grafts are rejected.
3. Penicillin is a hapten in both humans and mice. To explore the hapten-carrier relationship, a mouse
was injected with penicillin covalently bound to bovine serum albumin and, at the same time, with egg
albumin to which no penicillin was bound. Of the following, which one will induce a secondary
response to penicillin when injected into the mouse 1 month later?
A. penicillin
B. penicillin bound to egg albumin
C. egg albumin
D. bovine serum albumin
4. AIDS is caused by a human retrovirus that kills
A. B lymphocytes.
B. lymphocyte stem cells.
C. CD4-positive T lymphocytes.
D. CD8-positive T lymphocytes.
5. Polyomavirus (a DNA virus) causes tumors in "nude mice" (nude mice do not have a thymus,
because of a genetic defect) but not in normal mice. the BEST interpretation is that
A. macrophages are required to reject polyomavirus-induced tumors.
B. natural killer cells can reject polyomavirus-induced tumors without help from T lymphocytes.
C. T lymphocytes play an important role in the rejection of polyomavirus-induced tumors.
D. B lymphocytes play no role in rejection of polyomavirus-induced tumors.
6. After binding to its specific antigen, a B lymphocyte may switch its
A. immunoglobulin light-chain isotype.
B. immunoglobulin heavy-chain class.
C. variable region of the immunoglobulin heavy chain.
D. constant region of the immunoglobulin light chain.
-27. Antibody diversity is an important feature of the immune system. Which one of the following
statements about it is INCORRECT?
A. Humans can make antibodies to approximately 1 x 107 epitopes
B. A single cell can synthesize IgM antibody, then switch to IgA antibody.
C. heavy chain V region diversity is generated by VDJ joining
D. A single B lymphocyte can produce antibodies of many different epitopes, but a plasma cell is
monospecific.
8. Idiotypic determinants are located within
A. hypervariable regions of heavy and light chains.
B. constant regions of light chains.
C. constant regions of heavy chains.
D. the hinge region.
9. The membrane IgM and IgD on the surface of an individual B cell
A. have identical heavy chains but different light chains
B. are identical except for their CH regions
C. are identical except for their VH regions
D. have different VH and VL regions
10. During the maturation of a B lymphocyte, the first immunoglobulin heavy chain synthesized is the
A. Mu chain.
B. gamma chain.
C. epsilon chain.
D. alpha chain.
11. In the immune response to a hapten-protein conjugate, in order to get anti-hapten antibodies it is
essential that
A. the hapten be recognized by helper T cells.
B. the protein be recognized by helper T cells.
C. the protein be recognized by B cells.
D. the hapten be recognized by suppressor T cells.
12. An antibody directed against the idiotypic determinants of a human IgG antibody would react with
A. the Fc part of the IgG.
B. an IgM antibody produced by the same plasma cell that produced the IgG.
C. all human kappa chains.
D. all human gamma chains.
13. Which one of the following is NOT true of the gene segments that combine to make up a heavychain gene?
A. Many V region segments are available.
B. Several J segments and several D segments are available.
C. V, D, and J segments combine to encode the antigen-binding site.
D. A V segment and a J segment are preselected by an antigen to make up the variable-region portion of
the gene.
14. The antibody-binding site is formed by
A. the constant regions of H and L chains.
B. the hypervariable regions of H and L chains.
C. the hypervariable regions of H chains.
D. the variable regions of H chains.
E. the hypervariable regions of L chains.
-315. The class of immunoglobulin present in highest concentration in the blood of a human newborn is
A. IgG.
B. IgM.
C. IgA.
D. IgD.
E. IgE.
16. Antigen-presenting cells that activate helper T cells must express which one of the following on
their surfaces?
A. IgE
B. gamma interferon
C. class I MHC proteins
D. class II MHC proteins
17. Tumor rejection within an individual is mediated primarily by
A. non-complement-fixing antibodies.
B. phagocytic cells.
C. helper T cells.
D. cytotoxic T cells.
18. Which one of the following properties of antibodies is NOT dependent on the structure of the
heavy-chain constant region?
A. ability to cross the placenta
B. isotype (class)
C. ability to fix complement
D. affinity for antigen
19. Your patient became ill 10 days ago with a viral disease. Laboratory examination reveals that the
patient's antibodies against this virus have a high ratio of IgM to IgG. What is your conclusion?
A. It is unlikely that the patient has encountered this organism previously.
B. The patient is predisposed to IgE-mediated hypersensitivity reactions.
C. The patient is lacking complement
D. It is likely that the patient has an autoimmune disease.
20. Your patient is a child who has no detectable T or B cells. This immunodeficiency is most probably
the result of a defect in
A. the thymus.
B. the bursal equivalent.
C. T cell-B cell interaction.
D. stem cells originating in the bone marrow.
21. The role of the macrophage during an antibody response is to
A. make antibody.
B. lyse virus-infected target cells.
C. activate cytotoxic T cells.
D. process antigen and present it.
22. Each of the following statements concerning class II MHC proteins is correct EXCEPT:
A. They are found on the surface of both B and T cells.
B. They have a high degree of polymorphism.
C. They are involved in the presentation of antigen by macrophages.
D. They have a binding site for CD4 proteins.
-423. Which one of the following statements concerning immunoglobulin allotypes is CORRECT?
A. Allotypes are found only on heavy chains.
B. Allotypes are determined by class I MHC genes.
C. Allotypes are confined to the variable regions.
D. Allotypes are due to genetic polymorphism within a species.
24. Each of the following statements concerning haptens is correct EXCEPT:
A. A hapten can combine with (bind to) an antibody.
B. A hapten cannot induce an antibody by itself; rather, it must be bound to a carrier protein to be able to
induce antibody.
C. In both penicillin-induced anaphylaxis and poison ivy, the allergens are haptens.
D. Haptens must be processed by CD8+ cells to become immunogenic.
25. All of the following are true with respect to IgM antibodies EXCEPT which one
A.they fix complement
B.they occur on the surface of lymphocytes
C.they predominate in the primary response to antigen
D.they are glycoproteins
E.they mediate allergic reaction
26. One principal function of the Class I and Class II major histocompatibility complex proteins is to
A.transduce the signal to the T-cell interior following antigen binding
B.mediate immunoglobulin class switching
C.present antigen for recognition by the T-cell antigen receptor
D.stimulate production of interleukins
E.bind complement
27. A major role of the complement system is to work in conjunction with
A. antibodies to lyse cells
B. the major histocompatibility complex for cell recognition
C. antibodies to opsonize cells
D. the T-cell receptor for production of lymphokines
28. T-cell antigen receptors are distinguished from antibodies by which of the following
A.T-Cell receptors are glycosylated
B.T-cell receptors must interact with antigen uniquely presented by other cells but not with free antigen
C.T-Cell receptors bind various cytokines
D.T-Cell receptors bind complement to lyse cells
E.T-cell receptors are mediators of allergic reactions
29. Antigens
A.interact with antibodies.
B.contain antigenic determinants.
C.can elicit an immune response.
D.A and B are correct
E.A, B, and C are correct
-530. Which of the following immunoglobulins is present normally in plasma at the highest
concentration?
A.IgG
B.IgM
C.IgA
D.IgD
E.IgE
31. IgG proteins
A.are composed of two identical heavy and two identical light chains
B.are secreted by plasma cells
C.are expressed on membrane of T cells
D.A and B are correct
E.A, B and C are correct
32. Which immunoglobulin is the principal one found in secretions such as milk?
A.IgG
B.IgM
C.IgA
D.IgD
E.IgE
33. When a B-cell undergoes immunoglobulin class switching
A.the variable region of the light chain changes, but its constant region remains the same
B.the variable region of the light chain remains the same, but its constant region changes
C.the variable region of the heavy chain remains the same but its constant region changes
D.the variable region of the heavy chain changes but its constant region remains the same
E.both the variable and constant regions change
34. The class of an immunoglobulin
A.is determined by Class I and Class II major histocompatibility complex proteins
B.is determined by the carbohydrate attached to the light chain is
C.determined by the antigen
D.is determined by the heavy chain
E.Is determined by the J-chain
35. Light chains
A.are referred to as classes
B.are composed of V, D, J, and C regions
C.C region is able to fix complement
D.A and C are correct
E.all of the above are incorrect
-636. Each of the following is a characteristic of antibodies, EXCEPT which one?
A.they are proteins with variable and constant regions
B.they contain carbohydrates
C.they are only secreted by T-cells
D.they can combine very specifically with antigen
E.they are structurally organized in globular domains
37. Natural killer cells
A.are B cells that can kill without complement.
B.are cytotoxic T cells.
C.are increased by immunization.
D.can take part in ADCC (antibody dependent cell mediated cytotoxicity).
38. All of the following are true with respect to IgG antibodies EXCEPT which one
A. they can be bound by macrophages during opsonization
B. they occur on the surface of lymphocytes
C. they predominate in the secondary response to antigen
D. they are glycoproteins
E. they exist as a pentamer
39. All of the following are true when making monoclonal antibodies directed to a particular antigen,
EXCEPT
A. a myeloma cell is fused with a B cell
B. Secondary antibodies are directed to the antigen.
C. A hybridoma is created
D. Screening is necessary to identify the reactive B cell clones
E. PEG is used as a fusion agent
40. What is the purpose of fusing a myeloma cell to the B cell?
A. to allow the antibodies to bind to multiple epitopes
B. to create a hybridoma cell that makes an unlimited supply of a specific antibody
C. to increase presentation to T helper cells
D. none of the above
41. SCID mice
A. do not have a thymus
B. have a competent immune response system
C. have deleted RAG 1 and RAG 2 genes
D. express immunoglobulins on B cells
42. Inability to make antibodies to a hapten complexed to a carrier protein in a particular strain of mice
is due to:
A. absence of B cells with ability to recognize the hapten
B. defective macrophage antigen presenting cells
C. genetic defect in class I MHC genes
D. genetic defect in class II MHC genes
-743. Toll-like receptors (TLR4) can recognize and be activated by
A. peptides of 8 amino acids
B. peptides of 14 amino acids
C. only peptides from bacteria
D. bacterial lipopolysaccharides (LPS)
44. Excess T cells following an immune response are eliminated by
A. phagoctosis by macrophages and neutrophils
B. killing by NK cells
C. cell death by necrosis
D. cell death by apoptosis
45. A pluripotent stem cell in the bone marrow can give rise to
A. lymphoid progenitor cells
B. myeloid progenitor cells
C. erythrocytes
D. macrophages
E. all of the above
46. A receptor that binds immunoglobulin (antibody) to cell surface of NK cells is called
A. complement receptor
B. Fc receptor
C. Fas receptor
D. CD molecule
E. adhesion receptor
47. Exogenous antigen processing occurs mainly within
A. T lymphocytes
B. plasma cells
D. erythroid cells
C. macrophages
E. none of the above
48. Tonegawa provided definitive proof that V and C regions in genomic DNA from embryonic mice
were separate, and in myeloma cells were together. What procedure that he use to make this finding?
A. western blotting
B. amino acid sequencing
C. southern blotting
D. northern blotting
E. nucleotide sequencing
49. Kappa and lambda light chain genes
A. are located on the same chromosome
B. use same V-region genes
C. can be expressed together in a B cell immunoglobulin
D. A and B are correct
E. none of the above
50. A B cell becomes immunocompetent
A. following productive rearrangement of variable region heavy chain gene segments in germ-line
DNA
B. following productive rearrangement of variable region heavy chain and light chain gene segments in
germ line DNA
C. following class switching
D. during affinity maturation
E. following binding to T helper cytokines to their receptors on the B cell.