Which of the following endocrine glands degenerates in old age ?

Options

A. Thyroid
B. Thymus
C. Parathyroid
D. Adrenal

Answer

**Step-by-Step Solution:**

1. **Identify the Endocrine Glands**: The question asks about which endocrine gland degenerates with age. The relevant glands to consider include the thymus gland, thyroid gland, parathyroid glands, and adrenal glands.

2. **Understand the Function of the Thymus Gland**: The thymus gland is responsible for producing thymosin, a hormone that plays a crucial role in the development and differentiation of T lymphocytes (T cells), which are essential for the immune response.

3. **Examine the Changes in the Thymus Gland with Age**: As individuals age, the thymus gland undergoes a process of involution, meaning it decreases in size and function. This reduction in size leads to a decline in the production of thymosin and, consequently, a decrease in immune function.

4. **Compare with Other Endocrine Glands**:
- The **thyroid gland** primarily regulates metabolism and does not significantly degenerate with age.
- The **parathyroid glands** are involved in calcium regulation and do not show significant degeneration.
- The **adrenal glands** produce hormones related to stress response and do not typically degenerate in old age.

5. **Conclusion**: Based on the information, the thymus gland is the only endocrine gland that degenerates significantly with age, leading to decreased immune function.

**Final Answer**: The thymus gland degenerates in old age.

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