Cockroach and other insects have exoskeleton made up of :

Options

A. Keratin
B. Spongin
C. Chitin
D. Cuticle

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:**
The question asks about the composition of the exoskeleton in cockroaches and other insects.

2. **Identifying the Options:**
The options provided are:
- Keratin
- Spongin
- Chitin
- Cuticle

3. **Analyzing Each Option:**
- **Keratin:** This is a fibrous protein found in hair, nails, and the outer layer of skin in animals, but it is not found in the exoskeleton of insects.
- **Spongin:** This is a protein that makes up the skeleton of sponges, not insects.
- **Chitin:** This is a long-chain polymer that is a primary component of the exoskeletons of arthropods, including insects like cockroaches.
- **Cuticle:** While cuticle refers to a protective layer, it is not a specific material but rather a term that can describe various protective layers in different organisms.

4. **Conclusion:**
The correct answer is **Chitin**. The exoskeleton of cockroaches and other insects is primarily made up of chitin, which provides protection and support.

5. **Additional Information:**
The exoskeleton can also contain calcium carbonate, which adds toughness. The process of shedding the exoskeleton is known as molting.

**Final Answer:**
Cockroach and other insects have exoskeleton made up of **Chitin**.

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