Question

Primary lymphoid organs are

• A. Lymphoid structures formed directly over the lymph vessels
• B. Structures formed in the foetus
• C. Structures where lymphocytes mature /undergo preprocessing
• D. Lymphatic structures where mature lymphocytes reside

Answer 1

The correct option is C Structures where lymphocytes mature /undergo preprocessing

The primary or central lymphoid organs generate lymphocytes from immature progenitor cells. The thymus and the bone marrow constitute the primary lymphoid organs which is involved in the production and early clonal selection of lymphocyte tissues. Bone marrow is responsible for both the production of T cells and the production and maturation of B cells. The thymus is important for maturation of T-cells.

So, the correct answer is 'Structures where lymphocytes mature or undergo processing'.