ANATOMY

Detailed explanation-1: -B cells secrete antibodies that contribute to tissue injury via multiple mechanisms. In addition, B cells contribute to disease pathogenesis in autoimmunity and alloimmunity by presenting antigens as well as providing costimulation and cytokines to T cells.

Detailed explanation-2: -They function in the humoral immunity component of the adaptive immune system. B cells produce antibody molecules which may be either secreted or inserted into the plasma membrane where they serve as a part of B-cell receptors.

Detailed explanation-3: -IgM is not only the first class of antibody to appear on the surface of a developing B cell. It is also the major class secreted into the blood in the early stages of a primary antibody response, on first exposure to an antigen.

Detailed explanation-4: -Plasma cells, also called plasma B cells or effector B cells, are white blood cells that originate in the lymphoid organs as B lymphocytes and secrete large quantities of proteins called antibodies in response to being presented specific substances called antigens.

Detailed explanation-5: -Human lymphoid organs. Lymphocytes develop in the thymus and bone marrow (yellow), which are therefore called central (or primary) lymphoid organs.