Protein present in silk fibres are

Options

A. a basket made of pollen
B. a simple basket
C. sac in flowers where pollen are carried
D. cavity in hind leg of a worker bee

Answer

**Step-by-Step Solution:**

1. **Identify the Source of Silk Fibers:**
Silk fibers are produced by the silkworm during its life cycle, specifically when it forms a cocoon.

2. **Understand the Composition of Silk:**
Silk is primarily composed of proteins. The two main proteins found in silk fibers are fibroin and sericin.

3. **Differentiate Between the Two Proteins:**
- **Fibroin:** This is the primary structural protein that makes up about 70-80% of silk. It provides strength and structure to the silk fibers.
- **Sericin:** This is a secondary protein that makes up about 20-30% of silk. It acts as a gum or adhesive that helps to bind the fibroin fibers together.

4. **Summarize the Protein Content:**
In summary, silk fibers are composed of:
- 70-80% Fibroin (structural protein)
- 20-30% Sericin (adhesive protein)

5. **Conclude the Answer:**
Therefore, the proteins present in silk fibers are fibroin and sericin.

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