IMMUNOLOGY

Detailed explanation-1: -Some of the activated B cells transform into memory cells and become part of the “memory” of the adaptive immune system. The various cells of the adaptive immune system communicate either directly or via soluble chemical messengers such as cytokines (small proteins).

Detailed explanation-2: -Memory is a characteristic recognized within both the innate and adaptive arms of the immune system. Although the mechanisms and properties through which innate and adaptive immune memory are induced are distinct, they collude to improve host defense to pathogens.

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.