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Assertion: Immune response of old person...

Assertion: Immune response of old persons become weak.
Reason: Thymus degenerates in old individuals.

A

(a) Both, Assertion and Reason, are true and Reason is the correct explanation of Assertion

B

(b) Both, Assertion and Reason, are true but Reason is not the correct explanation of Assertion

C

(c) If Assertion is true but Reason is false

D

(d) If Assertion is false but Reason is true

Text Solution

Verified by Experts

The correct Answer is:
A
Thymus plays a major role in the development of the immune system. This gland secretes the peptide hormones called thymosins. Thymosins play a major role in the differentitation of T-lymphocytes, which provide cell-mediated immunity In addition, thymosins also promote production of antibodies to provide humoral immunity Thymus id degenerated in old individuals resulting in a decreased production of thymosins. As a result, the immune responses of old persons become weak.
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