Mammalian thymus' is mainly concerned with

Options

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

Answer

**Step-by-Step Solution:**

1. **Understanding the Thymus Gland**: The thymus is a bilobed lymphoid organ located in the upper part of the sternum, just in front of the heart. It plays a crucial role in the immune system.

2. **Identifying the Functions of the Thymus**: The primary function of the thymus gland is related to the immune system, specifically in the development and maturation of T cells (T lymphocytes), which are essential for the adaptive immune response.

3. **Evaluating the Options**:
- **Option A**: Regulation of body temperature - This is not a function of the thymus.
- **Option B**: Regulation of body growth - This is also not a function of the thymus.
- **Option C**: Immunological functions - This is the correct function of the thymus, as it is involved in the development of T cells.
- **Option D**: Secretion of thyrotropin - This is incorrect as thyrotropin (TSH) is secreted by the pituitary gland, not the thymus.

4. **Conclusion**: Based on the functions of the thymus gland, the correct answer is that the mammalian thymus is mainly concerned with **immunological functions**.

**Final Answer**: C. Immunological functions.

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