Which forms nails, hair and feathers

Options

A. Keratan sulphate
B. Keratin
C. Collagen
D. Elastin.

Answer

**Step-by-Step Solution:**

1. **Identify the components of nails, hair, and feathers**: Nails, hair, and feathers are all external structures found in animals.

2. **Understand the types of proteins**: The question provides four options: keratin sulfate, keratin, collagen, and elastin. We need to determine which of these proteins is responsible for forming nails, hair, and feathers.

3. **Analyze each option**:
- **Keratin Sulfate**: This is a sulfated glycosaminoglycan found in the cornea and cartilage, primarily involved in corneal development. It does not form nails, hair, or feathers.
- **Keratin**: This is a fibrous protein that is a major component of nails, hair, and feathers. It is known as alpha keratin in vertebrates and is a type of scleroprotein.
- **Collagen**: This protein is primarily found in the skin and is responsible for skin elasticity and structure. It does not form nails, hair, or feathers.
- **Elastin**: Similar to collagen, elastin is found in the skin and contributes to its elasticity. It does not contribute to the formation of nails, hair, or feathers.

4. **Select the correct answer**: Based on the analysis, the only protein that forms nails, hair, and feathers is **keratin**.

5. **Conclude the answer**: Therefore, the correct answer to the question "Which forms nails, hair, and feathers?" is **keratin**.

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