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Human Health and Disease — BIOLOGY STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 ScienceBIOLOGYHuman Health and Disease3 Marks
Question
Why are lymph nodes and bone marrow called lymphoid organs? Explain the functions of each of them.
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Answer

  • Since lymph nodes and bone marrow are the organs where origin and/ or maturation and proliferation of lymphocytes occur, they are called lymphoid organs.
  • Lymph nodes serve to trap the microorganisms or other antigens that enter the lymph; the lymphocytes in the lymph are then activated by these foreign molecules/ organisms to mount an immuneresponse. 
  • Bone marrow is the primary lymphoid organ where lymphocytes are produced.

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