Which of the following hormones is a steroid ?

Options

A. Oestrogen
B. Insulin
C. Glucagon
D. Thyroxine

Answer

To determine which hormone is a steroid, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Hormone Classification**: Hormones can be classified based on their chemical structure into four main types:
- Iodothyronines
- Amino acid derivatives
- Peptides or polypeptides (protein hormones)
- Steroidal hormones

2. **Identify Steroidal Hormones**: Steroidal hormones are derived from cholesterol and include sex hormones. Common examples include:
- Estrogen
- Progesterone
- Testosterone

3. **Analyze the Given Hormones**:
- **Estrogen**: A steroid hormone produced by the ovaries.
- **Insulin**: A peptide hormone produced by the pancreas.
- **Glucagon**: Also a peptide hormone produced by the pancreas.
- **Thyroxine**: An iodothyronine hormone produced by the thyroid gland.

4. **Select the Steroid Hormone**: Among the hormones listed, estrogen is the only one that is classified as a steroid hormone.

5. **Conclusion**: Therefore, the hormone that is a steroid is **Estrogen**.

### Final Answer:
The hormone that is a steroid is **Estrogen**.

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