MICROANATOMY

Detailed explanation-1: -Primary lymphoid organs: These organs include the bone marrow and the thymus. They create special immune system cells called lymphocytes. Secondary lymphoid organs: These organs include the lymph nodes, the spleen, the tonsils and certain tissue in various mucous membrane layers in the body (for instance in the bowel).

Detailed explanation-2: -The thymus is responsible for producing and maturing lymphocytes, or immune cells. These include T cells, a type of white blood cell that defends the body from infections. Additionally, the thymus suppresses the effects of aging, according to a 2016 study.

Detailed explanation-3: -The thymus tissue is distinguishable into an outer zone, the cortex, and an inner zone, the medulla. The organ is composed principally of two types of cells, called, respectively, lymphocytes (specifically, T cells, B cells, and natural killer cells) and reticular cells.