Which of the following is not related with thymosins ?

Options

A. In addition to cell mediated immunity, thymosins also promote production of antibodies to provide humoral immunity
B. In old age, thymosins production is more, so immunity is strong
C. Tymosins are produced by thyroid gland
D. Both b and c

Answer

To determine which of the following options is not related to thymosins, we need to analyze the functions and sources of thymosins, particularly thymoxin, and its relation to the immune system.

### Step-by-Step Solution:

1. **Identify the Source of Thymosins**:
- Thymosins, including thymoxin, are hormones produced by the thymus gland.

2. **Understand the Role of Thymosins**:
- Thymosins play a crucial role in the immune system, particularly in the maturation of T lymphocytes (T cells), which are essential for cell-mediated immunity.

3. **Differentiate Between Types of Immunity**:
- T lymphocytes are responsible for cell-mediated immunity, while B lymphocytes are responsible for humoral immunity by producing antibodies.

4. **Evaluate the Function of Thymosins**:
- Thymosin promotes the production of T cells and influences the immune response, including the production of antibodies by B cells.

5. **Consider the Impact of Age on Thymosins**:
- It is important to note that the thymus gland degenerates with age, leading to a decrease in thymosin production, which can weaken the immune response.

6. **Identify the Incorrect Option**:
- Since thymosin is produced by the thymus gland and not the thyroid gland, any option that states thymosin is produced by the thyroid gland would be incorrect.

### Conclusion:
The option that states thymosin is produced by the thyroid gland is not related to thymosins.

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