IMG58 (4)

33. ProUferation of large pre-B ceifs

a. is part of clonal selection

makes the pre-B cells morę susceptible to apoptosis fotłowing self antigen binding ^£. resułts in production of many B cells with the same antigen specificity.

j d. kesults in the production of many B cells with the same VH Chain but different antigen speciftcities due -ef&ferent VL regions

e regułres the presence of RAG-1 and RAG-2.

36. T independent antigens do NOT jgfbind to BCR.

'b. get presented on MHC Class II.

ę. have repeating epitopes.    '    ,

drfńduce B celi proliferation.

J provide co-stimulatory signals to B cells

37. Before a B celi can receive T celi help, the B celi must

a.    express membranę B7.

b.    express membranę CD40L.

c.    express membranę IFNy receptors.

d.    go to the site of infection.

e.    process and present peptide on Class ll MHC.

38. Isotype switching by B cells occurs in response to T celi

^v a. IFNy. i b. IL-4. i c.lL-5.

J    d. IL-6.

m    e. all of the above.

39. In order for T cells to provide help to B cells, T celi and B celi epitopes must be

a.    covalently linked.

b.    identical.

c.    non-identical. sff. peptides.

'ilT-dependent.

40. Humoral immunity involves all of the following EXCEPT

a antibody-dependent cell-mediated cytotoxicity. b, antibody secretion by plasma cells.

10.10

B celi activation by antigen plus cytokines. immunoglobulin isotype switching. macrophage activation by Th1 cells