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Chemical Coordination and integration — BIOLOGY STD 11 Science — Question

Rajasthan BoardEnglish MediumSTD 11 ScienceBIOLOGYChemical Coordination and integration2 Marks
Question
Old people have weak immune system. What could be the reason?
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Answer

The thymus gland secretes the hormone thymosin which plays a major role in differentiation of T-lymphocytes. T-lymphocytes are responsible for cell mediated immune response. In old age, the thymus gland gets degenerated resulting in reduced production of thymosin. Hence, old people have weak immune system.

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