Question

Identify the set of secondary lymphoid organs from the following :

• A. Bone marrow and lymph nodes
• B. Spleen and bone marrow
• C. Bone marrow and thymus gland
• D. Spleen and lymph nodes

Answer 1

The correct option is D Spleen and lymph nodes

• Lymphoid organs are of two types. They are primary lymphoid organs and secondary lymphoid organs.
• Primary lymphoid organs are the lymphoid organs in which lymphocytes are produced and undergo development and are then supplied to secondary lymphoid organs. For example, Bone marrow and thymus gland.
• Secondary lymphoid organs are the lymphoid organs in which lymphocytes are activated to participate in the specific immune response. For example, Appendix, lymph nodes, Tonsils, spleen, Peyer's patches of the small intestine, etc.
• Hence, Spleen and lymph nodes are the secondary lymphoid organs.
• So, the correct answer is 'Spleen and lymph nodes'.