Ramesh's grandfather falls ill repeatedly due to infections. The doctor says it's because his immunity is lowered owing to his old age. Which of the following is likely to be affected ?

Options

A. Thyroid gland
B. Pituitary gland
C. Adrenals
D. Thymus

Answer

To solve the question regarding Ramesh's grandfather and the impact of aging on his immunity, we need to identify which gland is likely affected and how it relates to immunity. Here’s a step-by-step breakdown:

### Step 1: Understand the Problem
Ramesh's grandfather is experiencing repeated infections due to lowered immunity, which is attributed to his old age. We need to determine which gland is primarily responsible for immunity and is likely affected by aging.

### Step 2: Analyze the Options
The options provided are:
- A) Thyroid gland
- B) Pituitary gland
- C) Adrenal gland
- D) Thymus gland

### Step 3: Evaluate Each Gland
1. **Thyroid Gland**:
- Function: Secretes thyroxine, which regulates metabolism.
- Relation to Immunity: Does not play a significant role in immune response.

2. **Pituitary Gland**:
- Function: Known as the "master gland," it regulates other endocrine glands.
- Relation to Immunity: While it affects various body functions, it does not directly influence immunity.

3. **Adrenal Gland**:
- Function: Produces hormones like adrenaline and cortisol, which help manage stress and metabolism.
- Relation to Immunity: While it can influence immune response indirectly, it is not the primary gland responsible for immunity.

4. **Thymus Gland**:
- Function: A primary lymphoid organ responsible for the maturation of T-lymphocytes (a type of white blood cell crucial for immune response).
- Relation to Immunity: Directly involved in the immune system; its size and function decrease with age, leading to reduced immunity.

### Step 4: Identify the Correct Answer
Based on the analysis, the thymus gland (Option D) is the structure that is likely affected due to aging, leading to lowered immunity and increased susceptibility to infections.

### Conclusion
The answer to the question is **D) Thymus gland**.

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