GENERAL HISTOLOGY

Detailed explanation-1: -Memory T and B cells remain, however, and maintain a heightened ability to mount a response to a recurrence of infection with the same pathogen. The antibody and memory T cells remaining in an immunized individual also prevent the activation of naive B and T cells by the same antigen.

Detailed explanation-2: -Memory cells are the way that the immune system learns. Both B cells and T cells can become memory cells. These cells mainly live in the spleen, tonsils, lymph nodes, and bone marrow, although some of them circulate throughout the body as well.

Detailed explanation-3: -Adaptive immune responses are carried out by white blood cells called lymphocytes. There are two broad classes of such responses-antibody responses and cell-mediated immune responses, and they are carried out by different classes of lymphocytes, called B cells and T cells, respectively.