It helps in differentiation of cells of immune system

Options

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

Answer

**Step-by-Step Solution:**

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

2. **Analyzing the Options**:
- **Cortisol**: This hormone is secreted by the adrenal cortex and is known for its role in producing anti-inflammatory reactions and suppressing the immune response. Therefore, it does not help in differentiation.
- **Thyroxine**: This hormone is produced by the thyroid gland and regulates metabolism and physical growth. It does not play a role in immune cell differentiation.
- **Thymosin**: This hormone is secreted by the thymus gland and is crucial for the differentiation of T lymphocytes, which are essential for cell-mediated immunity.
- **Steroids**: While steroids are secreted by the adrenal cortex and include hormones like cortisol and aldosterone, they do not specifically aid in the differentiation of immune cells.

3. **Identifying the Correct Answer**: Among the options, thymosin is the only one that specifically aids in the differentiation of T lymphocytes, which are vital for the immune response.

4. **Conclusion**: Therefore, the correct answer to the question is **Thymosin**.

**Final Answer**: Thymosin helps in the differentiation of cells of the immune system.

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