Chitin is

Options

A. Insoluble in water
B. Resistant to acids and alkalies
C. Insoluble in most organic solvents
D. All the above

Answer

**Step-by-Step Text Solution:**

1. **Definition of Chitin**: Chitin is a specific type of polysaccharide. It is a long-chain polymer made up of N-acetylglucosamine (GlcNAc) units, which are derived from glucose.

2. **Occurrence**: Chitin is primarily found in the cell walls of fungi. It serves a structural role, providing rigidity and strength to the cell wall, similar to how cellulose functions in plant cell walls.

3. **Properties of Chitin**:
- **Insolubility in Water**: Chitin is insoluble in water, which means it does not dissolve when mixed with water. This property is important for its function in providing structural support.
- **Resistance to Acids and Alkalis**: Chitin is resistant to various acids and bases, making it durable and stable under different environmental conditions.
- **Insolubility in Most Organic Solvents**: Chitin is also insoluble in most organic solvents, which further contributes to its stability and resistance to degradation.

4. **Conclusion**: Given the properties of chitin, it can be concluded that chitin is a polysaccharide that is insoluble in water, resistant to acids and alkalis, and insoluble in most organic solvents.

**Final Answer**: Chitin is a polysaccharide found in the cell wall of fungi, and it is insoluble in water, resistant to acids and alkalis, and insoluble in most organic solvents.

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