Silk contains a proteins known as

Options

A. Fibroin
B. Caseia
C. Sericin
D. Both (1) and (3)

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks about the type of protein found in silk.

2. **Understand Silk Production**: Silk is obtained from the larvae of the silk moth, specifically the species known as *Bombyx mori*.

3. **Know the Types of Proteins in Silk**: Silk contains two main proteins:
- **Fibroin**: This is the primary fibrous protein that constitutes about 70-80% of silk.
- **Sericin**: This is a sticky protein that makes up about 20-30% of silk.

4. **Evaluate the Options**:
- **Fibroin**: Correct, as it is a protein found in silk.
- **Casein**: Incorrect, as it is a milk protein and not related to silk.
- **Sericin**: Correct, as it is also a protein found in silk.
- **Both 1 and 3**: This option is correct since both fibroin and sericin are proteins present in silk.

5. **Conclusion**: The correct answer to the question is "Both 1 and 3".

**Final Answer**: Silk contains proteins known as fibroin and sericin (Both 1 and 3).

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