Which is steroid hormone

Options

A. Epinephrine
B. Thyroxine
C. Estrogen
D. Gonadotropin

Answer

To determine which of the given options is a steroid hormone, we can follow these steps:

### Step-by-Step Solution:

1. **Understand what a steroid hormone is**:
- Steroid hormones are a class of hormones that are synthesized from cholesterol. They are lipid-soluble and can easily pass through cell membranes. Their receptors are typically located inside the cell.

2. **Analyze the options provided**:
- **Epinephrine**: This hormone is derived from the amino acid tyrosine and is classified as a catecholamine, not a steroid hormone.
- **Thyroxine**: This hormone is derived from the amino acid tyrosine as well, but it is classified as a thyroid hormone, not a steroid hormone.
- **Gonadotrophin**: This is a glycoprotein hormone that stimulates the gonads (ovaries and testes) and is not a steroid hormone.
- **Estrogen**: This hormone is produced by the ovarian follicles and is classified as a steroid hormone. It plays a crucial role in the development of secondary sexual characteristics in females.

3. **Identify the correct answer**:
- Among the options, estrogen is the only hormone that is classified as a steroid hormone.

### Conclusion:
The correct answer is **option number 3: estrogen**.

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