601. Fab fragment has
A. one antigen binding site
B. two antigen binding site
C. one antibody binding site
D. two antibody binding site

602. The main function of antibodies is to
A. kill all the foreign bodies
B. generate antigens, thus conferring immunization
C. protect the circulatory system
D. chemically combine with the antigen which induces it, inactivate the antigen and protect the body from disease

603. Alum is an effective adjuvant because it
A. disaggregates the antigen.
B. is immunogenic for stem cells
C. is immunogenic for T cells
D. slows the release of antigen

604. A secondary antibody is an antibody that
A. has been used in prior experiments
B. is synthetically produced
C. binds to another antibody
D. is produced in boostered animals

605. The immunoglobulin fold is
A. found only in IgG molecules
B. a β-barrel composed of a three- and a four-stranded antiparallel β-sheet
C. both (a) and (b)
D. found six times in the IgG molecule

606. Antibodies of the IgG class
A. consist of four subunits
B. are glycoproteins
C. are secreted into the bloodstream
D. all of the above

607. Each IgA antibody molecule consists of
A. four polypeptide chain and has two antigen binding site
B. two polypeptide chain and has one antigen binding site
C. three polypeptide chain and has two antigen binding site
D. two polypeptide chain and has two antigen binding site

608. Antibodies in the human immune system can identify approximately 108 different molecules Which one of the following is correct?
A. This diversity is generated from 108 different immunoglobin genes
B. Many of these molecules are self-antigens
C. Most of these antibodies recognize proteins
D. Most of these antibodies recognize small organic molecules

609. Monoclonal antibodies were first produced by
A. Georges Kohler and Cesar Milstein
B. Sarkar and Sommer
C. Selman Waksman
D. Edward Jenner and Louis Pasteur

610. A polyclonal antibody response
A. is produced only in response to polymeric antigens
B. is produced by several B cells recognizing different pitopes on the same antigen
C. occurs during the lag phase of the immune response
D. violates clonal selection