AP BIOLOGY

Detailed explanation-1: -B lymphocytes are the cells of the immune system that make antibodies to invading pathogens like viruses. They form memory cells that remember the same pathogen for faster antibody production in future infections.

Detailed explanation-2: -During the secondary immune response, the immune system can eliminate the antigen, which has been encountered by the individual during the primary invasion, more rapidly and efficiently. Both T and B memory cells contribute to the secondary response.

Detailed explanation-3: -Memory B cells are generated during primary responses to T-dependent vaccines. They do not produce antibodies, i.e., do not protect, unless re-exposure to antigen drives their differentiation into antibody producing plasma cells.

Detailed explanation-4: -Another hallmark of memory B cells is that they display and secrete antibodies with a markedly higher affinity than those produced by primary plasma cells, as a result of somatic hypermutation and selection.

Detailed explanation-5: -The B cells producing the antibodies remember the infection (germ) and provide long-lasting immunity to it. Similarly, T cells can remember viruses that the body has encountered and can make a more vigorous response when they encounter the same virus again.