It helps in differentiation of cells of immune system

Options

A. Cortisol
B. Thyroxine
C. Thymosin
D. Steroid

Answer

To solve the question "It helps in differentiation of cells of immune system," we need to identify which substance is responsible for this function. Let's analyze the options step by step:

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks for a substance that aids in the differentiation of immune system cells. Differentiation refers to the process by which cells develop into their specialized forms and functions.

2. **Analyzing Option A: Cortisol**:
- Cortisol is a hormone secreted by the adrenal gland.
- Its primary function is to suppress the immune system.
- **Conclusion**: Cortisol does not help in differentiation; hence, this option is incorrect.

3. **Analyzing Option B: Thyroxine**:
- Thyroxine is a hormone produced by the thyroid gland.
- It is mainly involved in regulating the basal metabolic rate and physical growth.
- **Conclusion**: Thyroxine does not play a role in the differentiation of immune cells; thus, this option is also incorrect.

4. **Analyzing Option C: Thymosine**:
- Thymosine is a protein found in many animals.
- It is specifically responsible for the differentiation of T lymphocytes, which are crucial for cell-mediated immunity.
- **Conclusion**: Thymosine is the correct answer as it directly aids in the differentiation of immune system cells.

5. **Analyzing Option D: Steroid**:
- Steroids are hormones secreted by the adrenal cortex.
- Examples include cortisol and androgens, which do not promote differentiation of immune cells.
- **Conclusion**: This option is incorrect as well.

### Final Answer:
The correct answer is **Thymosine** (Option C), as it is responsible for the differentiation of T lymphocytes in the immune system.

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