The ctinous axoskeleton of arthropoda is formed by polymerisation of

Options

A. Keratin sulphate and chondroitin sulphate
B. D-glucosamine
C. N-acetyl glucosamine
D. Lipoglycans.

Answer

To answer the question regarding the formation of the chitinous exoskeleton of arthropods, we can break down the solution into the following steps:

### Step-by-Step Solution:

1. **Understanding the Exoskeleton**: The exoskeleton of arthropods is a hard outer structure that provides support and protection. It is primarily made of a substance called chitin.

2. **Identifying Chitin**: Chitin is a long-chain polymer that is a derivative of glucose. It is a key component not only in the exoskeleton of arthropods but also in the cell walls of fungi.

3. **Polymerization Process**: The chitinous exoskeleton is formed through a process called polymerization, where smaller molecules (monomers) combine to form a larger molecule (polymer). In the case of chitin, the monomer is N-acetylglucosamine.

4. **Choosing the Correct Option**: Among the options provided:
- Carotene sulfate
- Chondroitin sulfate
- D-glucamine
- N-acetylglucosamine
- Lipo glycans

The correct answer is **N-acetylglucosamine**, as it is the monomer that polymerizes to form chitin.

5. **Conclusion**: Therefore, the chitinous exoskeleton of arthropods is formed by the polymerization of N-acetylglucosamine.

### Final Answer:
The chitinous exoskeleton of arthropods is formed by polymerization of **N-acetylglucosamine**.

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