Question

A functional immune system requires primary and secondary lymphoid organs.

a) Briefly describe the immunological processes that occur in primary lymphoid organs. (Marks: 6)

b) Briefly describe the immunological processes that occur in secondary lymphoid organs. (Marks: 6)

Answer 1

(a) Ans. Primary lymphocyte organs are the organs in our body where there is production and maturation of lymphocytes take place. Bone marrow and thymus are examples of primary lymphoid organs. Lymphocytes are white blood cells (WBCs) that play important role in immune system. Lymphocytes include B lyphocytes ( B cells) and T lymphocytes (T cells). The fuction of B cells is to produce antibodies interacting with particular antigens. T cells help in killing of infected cells in our body anfd hence it removes pathogens and prevents spread of pathogens futher by removing the infected cells.

(b) Ans. Secondary lymphoid organs are the organs of immune system such as spleen, lymph nodes, mucosal associated lymphoid tissue (MALT). These organs provide the site for interaction of lymphocytes with antigens and their activation occurs. They also maintain mature neive lymphocytes. Initiation of adaptive immune response takes place in which the pathogens already detected are protected for long term due to the presence memory cells.