Thymus is mainly concerned with -

Options

A. Regulation of body temperature
B. Regulation of body growth
C. Immunological functions
D. Secretion of thyrotropin

Answer

**Step-by-Step Solution:**

1. **Identify the Organ**: The question asks about the thymus gland, which is an important organ in the immune system.

2. **Understand the Function**: The thymus is primarily responsible for the maturation of T lymphocytes (T cells), which are crucial for the adaptive immune response.

3. **Hormonal Secretion**: The thymus secretes a hormone known as thymosin (often referred to as thymoxin in some contexts), which plays a vital role in the development and maturation of T cells.

4. **Primary Lymphoid Organ**: The thymus is classified as a primary lymphoid organ. Primary lymphoid organs are responsible for the formation and maturation of lymphocytes.

5. **Role in Immunity**: The main function of the thymus is related to the immune system, specifically in immunological functions, which involve fighting against pathogens and disease-causing agents.

6. **Conclusion**: Therefore, the thymus is mainly concerned with the maturation of T lymphocytes and plays a significant role in the immune response.

**Final Answer**: The thymus is mainly concerned with the maturation of T lymphocytes and plays a crucial role in the immune system.

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