Section I. Quantitative relationships


Each of the items numbered 1 through 25 consist of a pair labeled (1) and (2). Use the following key to indicate whether (1) is greater than, less than, or approximately equal to (2).

Check:
A. if (1) is greater than (2)
B. if (2) is greater than (1)
C. if (1) and (2) are approximately equal.

For example:

(1)The number of people living in Chicago.
(2)The number of people living in Carbondale.

In this example, (1) is greater than (2) so you should check circle A.
(Go ahead, try it! Then press the "GO!" button to begin the exam.)
























Question #1.



(1)The probability that the antigen-blocking mechanism proposed for regulation of the humoral response would be active when serum antibody levels are relatively low.
(2)The probability that the antigen-blocking mechanism proposed for regulation of the humoral response would be active when serum antibody levels are relatively high.




























Question #2.



(1)The ability of the Class II MHC molecule to interact with CD4+ T-cells.
(2)The ability of the Class II MHC molecule to interact with CD8+ T-cells.



























Question #3.



(1)The role of the Class I MHC molecule in the presentation of “exogenous” antigen.
(2)The role of the Class I MHC molecule in the presentation of “endogenous” antigen.



























Question #4.



(1)The role of complement component C3a in promoting chemotaxis of phagocytic cells.
(2)The role of complement component C5a in promoting chemotaxis of phagocytic cells.




























Question #5.



(1)The role of the CTL in the elimination of “exogenous” antigens.
(2)The role of the CTL in the elimination of “endogenous” antigens.




























Question #6.



(1)The number of different immunoglobulin allotypes found in the human population.
(2)The number of different immunoglobulin idiotypes found in the human population.




























Question #7.



(1)The total number of different antigenic determinants that can be recognized by the entire repertoire of T-cell receptor molecules (TCR) in an individual.
(2)The total number of different antigenic determinants that can be recognized by the entire repertoire of B-cell receptor molecules (IgD) in an individual.




























Question #8.



(1)The tendency for most exotoxins to be produced by Gram-positive organisms.
(2)The tendency for most exotoxins to be produced by Gram-negative organisms.




























Question #9.



(1)The ability of Protein H to inhibit the production of C3b by inhibiting the binding of factor B to cell-membrane bound C3b.
(2)The ability of Factor I to inhibit the production of C3b by inhibiting the binding of factor B to cell-membrane bound C3b.




























Question #10.



(1)The immunogenicity of a large, complex molecule.
(2)The immunogenicity of a large, repetitive molecule.




























Question #11.



(1)The ability of a macrophage to kill an ingested non-encapsulated extracellular organism.
(2)The ability of a macrophage to kill an ingested encapsulated extracellular organism.

























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Question #12.



(1)The ability of a macrophage to serve as an Antigen-Presenting Cell (APC), leading to activation of a T-helper cell.
(2)The ability of a B-cell to serve as an Antigen-Presenting Cell (APC), leading to activation of a T-helper cell.

























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Question #13.



(1)The strength of the non-covalent forces maintaining an antibody-antigen interaction that has an affinity constant (K) of 5 x 108.
(2)The strength of the non-covalent forces maintaining an antibody-antigen interaction that has an affinity constant (K) of 2 x 1010.

























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Question #14.



(1)The extent of sheep red blood cell (SRBC) lysis in a complement fixation assay when the patient’s serum contains a low level of antibody.
(2)The extent of sheep red blood cell (SRBC) lysis in a complement fixation assay when the patient’s serum contains a high level of antibody.




























Question #15.



(1)The number of variable region domains in an immunoglobulin light chain.
(2)The number of constant region domains in an immunoglobulin light chain.




























Question #16.



(1)The number of days required to observe an antibody response following primary injection of an antigen.
(2)The number of days required to observe an antibody response following secondary injection of an antigen.




























Question #17.



(1)The likelihood that anaphylactic shock would result from a Type I hypersensitivity.
(2)The likelihood that anaphylactic shock would result from a Type IV hypersensitivity.




























Question #18.



(1)The extent of loss of total immune responsiveness in a patient with SCID.
(2)The extent of loss of total immune responsiveness in a patient with Hypogammaglobulinemia.




























Question #19.



(1)The ability of encapsulated strains of Streptococcus pneumoniae to escape phagocytosis by macrophages.
(2)The ability of non-encapsulated strains of Streptococcus pneumoniae to escape phagocytosis by macrophages.




























Question #20.



(1)The amount of evidence suggesting that the condition referred to as Autoimmune Hemolytic Anemia (AHA) results from a Type II hypersensitivity.
(2)The amount of evidence suggesting that the condition referred to as Autoimmune Hemolytic Anemia (AHA) results from a Type III hypersensitivity.




























Question #21.



(1)The number of polypeptides that make up a Class I MHC molecule.
(2)The number of polypeptides that make up a Class II MHC molecule.




























Question #22.



(1)Participation of K-cells in the process termed Antibody-dependent Cell-mediated Cytotoxicity (ADCC).
(2)Participation of NK-cells in the process termed Antibody-dependent Cell-mediated Cytotoxicity (ADCC).




























Question #23.



(1)The ability of B-lymphocytes to bind antibody via an immunoglobulin Fc receptor.
(2)The ability of T-lymphocytes to bind antibody via an immunoglobulin Fc receptor.




























Question #24.



(1)The ability of IgD to activate complement.
(2)The ability of IgE to activate complement.




























Question #25.



(1)The LD50 of a very virulent strain of Clostridium botulinum.
(2)The LD50 of a poorly virulent strain of Clostridium botulinum.