004

Question 1

Which of the following is a primary lymphoid organ?
a. Lymph node
b. Spleen
c. Thymus
d. MALT

Answer 1

c. Thymus

Question 2

What type of cells would be found in a primary follicle?
a. Unstimulated B cells
b. Germinal centers
c. Plasma cells
d. Memory cells

Answer 2

a. Unstimulated B cells

Question 3

Which of the following is true of NK cells?
a. They rely on memory for antigen recognition.
b. They share antigens with B cells.
c. They are found mainly in lymph nodes.
d. They recognize a lack of MHC proteins.

Answer 3

d. They recognize a lack of MHC proteins.

Question 4

Where are all undifferentiated lymphocytes made?
a. Bone marrow
b. Thymus
c. Spleen
d. Lymph nodes

Answer 4

d. Lymph nodes

Question 5

In the thymus, positive selection of immature T cells is based upon recognition of which of the following?
a. Self-antigens
b. Stress proteins
c. MHC antigens
d. μ chains

Answer 5

c. MHC antigens

Question 6

Which of these are found on a mature B cell?
a. IgG and IgD
b. IgM and IgD
c. Alpha and beta chains
d. CD3

Answer 6

b. IgM and IgD

Question 7

Which receptor on T cells is responsible for rosetting with sheep red blood cells?
a. CD2
b. CD3
c. CD4
d. CD8

Answer 7

a. CD2

Question 8

Which of the following can be attributed to antigen-stimulated T cells?
a. Humoral response
b. Plasma cells
c. Cytokines
d. Antibody

Answer 8

c. Cytokines

Question 9

Which is a distinguishing feature of a pre-B cell?
a. μ chains in the cytoplasm
b. Complete IgM on the surface
c. Presence of CD21 antigen
d. Presence of CD25 antigen

Answer 9

a. μ chains in the cytoplasm

Question 10

When does genetic rearrangement for coding of light chains take place?
a. Before the pre-B cell stage
b. As the cell becomes an immature B cell
c. Not until the cell becomes a mature B cell
d. When the B cell becomes a plasma cell

Answer 10

b. As the cell becomes an immature B cell

Question 11

Which of the following antigens are found on the T cell subset known as helper/inducers?
a. CD3
b CD4
c. CD8
d. CD11

Answer 11

b CD4

Question 12

Where does the major portion of antibody production occur?
a. Peripheral blood
b. Bone marrow
c. Thymus
d. Lymph nodes

Answer 12

d. Lymph nodes

Question 13

Which of the following would represent a double-negative thymocyte?
a. CD2–CD3+CD4–CD8+
b. CD2+CD3–CD4–CD8–
c. CD2–CD3+CD4+CD8–
d. CD2+CD3+CD4+CD8–

Answer 13

b. CD2+CD3–CD4–CD8–

Question 14

Which of the following best describes the T-cell receptor for antigen?
a. It consists of IgM and IgD molecules.
b. It is the same for all T cells.
c. It is present in the double-negative stage.
d. Alpha and beta chains are unique for each antigen.

Answer 14

d. Alpha and beta chains are unique for each antigen.

Question 15

All of the following are characteristic of a good immunogen except
a. internal complexity.
b. large molecular weight.
c. the presence of numerous epitopes.
d. found on host cells.

Answer 15

d. found on host cells.

Question 16

Which of the following best describes a hapten?
a. Not able to react with antibody
b. Antigenic only when coupled to a carrier
c. Has multiple determinant sites
d. A large chemically complex molecule

Answer 16

b. Antigenic only when coupled to a carrier

Question 17

Which would be the best immunogen?
a. Protein with a molecular weight of 200,000
b. Nylon
c. Polysaccharide with a molecular weight of 250,000
d. Protein with a molecular weight of 175,000

Answer 17

a. Protein with a molecular weight of 200,000

Question 18

All of the following describe an epitope except
a. same as an antigenic determinant site.
b. area of an immunogen recognized by T cells.
c. consists of sequential amino acids only.
d. key portion of the immunogen.

Answer 18

c. consists of sequential amino acids only.

Question 19

Adjuvents act by which of the following methods?
a. Complex to antigen to increase its size
b. Prevent rapid escape from the tissues
c. Increase processing of antigen
d. All of the above

Answer 19

d. All of the above

Question 20

A heterophile antigen is one that
a. is a self-antigen.
b. exists in unrelated plants or animals.
c. has been used previously to stimulate antibody response.
d. is from the same species but is different from the host.

Answer 20

b. exists in unrelated plants or animals.

Question 21

Which of the following is true of MHC (HLA) class II antigens?
a. They are found on all nucleated cells.
b. They are found on B cells and macrophages.
c. They all originate at one locus.
d. They are coded for on chromosome 9.

Answer 21

b. They are found on B cells and macrophages.

Question 22

MHC molecules are associated with which of the following?
a. Graft rejection
b. Autoimmune diseases
c. Determining to which antigens an individual responds
d. All of the above

Answer 22

d. All of the above

Question 23

Which of the following best describes the role of TAP?
a. They bind to class II molecules to help block the antigen-binding site.
b. They bind to class I proteins in proteosomes.
c. They transport peptides into the lumen of the endoplasmic reticulum.
d. They help cleave peptides for transport to endosomes.

Answer 23

c. They transport peptides into the lumen of the endoplasmic reticulum

Question 24

An individual is recovering from a bacterial infection and tests positive for antibodies to a protein normally found in the cytoplasm of this bacterium. Which of the following statements is true of this situation?
a. Class I molecules have presented bacterial antigen to CD8+ T cells.
b. Class I molecules have presented bacterial antigen to CD4+ T cells.
c. Class II molecules have presented bacterial antigen to CD4+ T cells.
d. B cells have recognized bacterial antigen without help from T cells.

Answer 24

c. Class II molecules have presented bacterial antigen to CD4+ T cells.

Question 25

Which is characteristic of variable domains of immunoglobulins? a. They occur on both the H and L chains. b. They represent the complement binding site. c. They are at the carboxy-terminal ends of the molecules. d. All of the above

Answer 25

a. They occur on both the H and L chains.

Question 26

All of the following are true of IgM except that it a. can cross the placenta. b. fixes complement. c. has a J chain. d. is a primary response antibody.

Answer 26

a. can cross the placenta.

Question 27

How many antigen binding sites does a typical IgM molecule have? a. 2 b. 4 c. 6 d. 10

Answer 27

d. 10

Question 28

Bence-Jones proteins are identical to which of the following? a. H chains b. L chains c. IgM molecules d. IgG molecules

Answer 28

b. L chains

Question 29

A Fab fragment consists of a. two H chains. b. two L chains. c. one L chain and one-half of an H chain. d. one L chain and an entire H chain.

Answer 29

c. one L chain and one-half of an H chain.

Question 30

Which of the following pairs represents two different immunoglobulin allotypes? a. IgM and IgG b. IgM1 and IgM2 c. Antihuman IgM and antihuman IgG d. IgG1m3 and IgG1m17

Answer 30

d. IgG1m3 and IgG1m17

Question 31

Which of the following are L chains of antibody molecules? a. kappa b. gamma c. mu d. alpha

Answer 31

a. kappa

Question 32

If the results of serum protein electrophoresis show a significant decrease in the gamma band, which of the following is a likely possibility? a. Normal response to active infection b. Muliple myeloma c. Immunodeficiency disorder d. Monoclonal gammopathy

Answer 32

c. Immunodeficiency disorder

Question 33

The subclasses of IgG differ mainly in a. the type of L chain. b. the arrangement of disulfide bonds. c. the ability to act as opsonins. d. molecular weight.

Answer 33

b. the arrangement of disulfide bonds.

Question 34

Which best describes the role of the SC of IgA? a. A transport mechanism across endothelial cells b. A means of joining two IgA monomers together c. An aid to trapping antigen d. Enhancement of complement fixation by the classical pathway

Answer 34

a. A transport mechanism across endothelial cells

Question 35

Which represents the main function of IgD? a. Protection of the mucous membranes b. Removal of antigens by complement fixation c. Enhancing proliferation of B cells d. Destruction of parasitic worms

Answer 35

c. Enhancing proliferation of B cells

Question 36

Which antibody is best at agglutination and complement fixation? a. IgA b. IgG c. IgD d. IgM

Answer 36

d. IgM

Question 37

Which of the following can be attributed to the clonal selection theory of antibody formation? a. Plasma cells make generalized antibody. b. B cells are preprogrammed for specific antibody synthesis. c. Proteins can alter their shape to conform to antigen. d. Cell receptors break off and become circulating antibody.

Answer 37

b. B cells are preprogrammed for specific antibody synthesis.

Question 38

All of the following are true of IgE except that it a. fails to fix complement. b. is heat stable. c. attaches to tissue mast cells. d. is found in the serum of allergic persons.

Answer 38

b. is heat stable.

Question 39

Which best describes coding for immunoglobulin molecules? a. All genes are located on the same chromosome. b. L chain rearrangement occurs before H chain rearrangement. c. Four different regions are involved in coding of H chains. d. λ rearrangement occurs before κ rearrangement.

Answer 39

c. Four different regions are involved in coding of H chains.

Question 40

What is the purpose of HAT medium in the preparation of monoclonal antibody? a. Fusion of the two cell types b. Restricting the growth of unfused myeloma cells. c. Restricting the growth of unfused spleen cells d. Restricting antibody production to the IgM class

Answer 40

b. Restricting the growth of unfused myeloma cells.