The chitinous exoskeleton of arthropods is formed by the polymerisation of :

Options

A. Kertain sulphate and chondroition sulphate
B. D-glucosamie
C. N-acetly glucosamie
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 Chitin**:
- The chitinous exoskeleton is a key feature of arthropods, such as insects, crustaceans, and arachnids. Chitin is a structural polysaccharide that provides rigidity and protection.

2. **Identifying the Monomer**:
- Chitin is formed by the polymerization of a specific monomer. The primary monomeric unit of chitin is N-acetylglucosamine. This compound is a derivative of glucose.

3. **Polymerization Process**:
- The process of polymerization involves the linking of multiple N-acetylglucosamine units to form long chains, resulting in the formation of chitin. This process is crucial for creating the structural integrity of the exoskeleton.

4. **Role of Chitin in Other Organisms**:
- Chitin is not only present in arthropods but also in the cell walls of fungi and the shells of some mollusks. This highlights the versatility and importance of chitin in various biological structures.

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 the polymerization of N-acetylglucosamine.

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