1. Large parasites such as helminths may be killed extracellularly by the action of

A. basophils
B. monocytes
C. eosinophils
D. neutrophils

2. Which of the following is correct for CD8 T cells?

A. CD8 T cells only recognize virus-infected cells
B. CD8 T cell receptor recognizes epitopes that are also commonly recognized by B cells
C. In the thymus, CD8 T cells undergo positive selection only, whereas CD4 T cells undergo negative selection
D. CD8 T cells can kill individual virus-infected cells in a contact-dependent fashion

3. Passive immunization is done for

A. tuberculosis
B. diphtheria
C. enteric fever
D. all of these

4. Which of the following is correct for isoantigens?

A. They are antigens found in all members of different species
B. They are antigens found in some members of a species
C. They are antigens found in all members of a species
D. They are antigens found in some members of different species

5. Numerous antibodies can be prepared, against one antigen, each binds to unique epitopes. How is this antibody diversity generated?

A. By rearrangements of the DNA encoding the variable regions of the heavy and light chains
B. By the combination of different heavy and light chains that form the antigen-binding site
C. Antibody proteins can physically change their shape to bind different epitopes
D. Both (a) and (b)