Class 12th Biology 2011 Set3 Delhi Board Paper Solution
Question 16
State the functions of primary and secondary lymphoid organs in humans.
Answer
Role of primary and secondary lymphoid organs in humans are:
Primary lymphoid organs: Here, immature lymphocytes are differentiated to form antigen-sensitive lymphocytes. Bone marrow and thymus are the examples of primary lymphoid organs.
Secondary lymphoid organs: Lymphocytes migrate here after attaining maturity. These organs provide an environment that enable mature lymphocytes to interact with each other, accessory cells and with antigens, resulting in the initiation of the antigen specific response. Spleen, lymph nodes tonsils, Peyer’s patches, and appendix are the examples of secondary lymphoid organs.
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