Growth rate in childhood is controlled by

Options

A. Thymosine
B. Thyroxine
C. Progesterone
D. Oestrogen

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the hormone that controls the growth rate in childhood. We need to identify which hormone among the given options is responsible for this.

2. **Examining the Options**: The options provided are:
- 1st: Thymosin
- 2nd: Thyroxin
- 3rd: Progesterone
- 4th: Estrogen

3. **Analyzing Each Hormone**:
- **Thymosin**: This hormone is produced by the thymus gland and is primarily involved in the development of T-cells, which are crucial for the immune response. While it plays a role in childhood, it is not directly responsible for growth.
- **Thyroxin**: This hormone is produced by the thyroid gland and is important for regulating metabolism and growth. It becomes more significant during puberty and beyond.
- **Progesterone**: This hormone is primarily involved in the menstrual cycle and pregnancy. It does not play a role in childhood growth.
- **Estrogen**: This hormone is involved in the development of secondary sexual characteristics and is more relevant during puberty.

4. **Identifying the Correct Answer**:
- Since the question specifically refers to childhood growth, the hormone that plays a significant role in growth during this period is **Thyroxin**. Although thymosin is important for immune function, it does not directly control growth.

5. **Conclusion**: The correct answer to the question "Growth rate in childhood is controlled by" is **Thyroxin**.

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