Keratin , a structural protein is present in

Options

A. Hair
B. Skin
C. Wool
D. All of these

Answer

**Step-by-Step Solution:**

1. **Understanding Keratin**: Keratin is a type of structural protein that is essential for the integrity and protection of various body parts. It is known for its fibrous structure and is a key component in the formation of protective layers.

2. **Identifying Locations of Keratin**: Keratin is primarily found in several outer body parts, including:
- **Hair**: Keratin forms the main structural component of hair, providing strength and resilience.
- **Skin**: The outer layer of skin, known as the epidermis, contains keratin which helps protect underlying tissues and prevents water loss.
- **Nails**: Keratin also makes up the hard structure of nails, providing durability and protection to the fingertips.

3. **Considering Wool**: Wool, which comes from sheep, is also composed of keratin. The protein structure in wool fibers is similar to that found in hair, making it a natural product derived from keratin.

4. **Conclusion**: Since keratin is present in hair, skin, nails, and wool, the correct answer to the question is that keratin is present in all of these options.

5. **Final Answer**: Therefore, the answer to the question is **all of these**.

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