Macro molecule chitin is:

Options

A. Sulphur containing polysaccharide
B. simple polysaccharide
C. nitrogen containing polysaccharide
D. phosphorus containing polysaccha- ride

Answer

**Step-by-Step Solution:**

1. **Definition of Chitin**: Chitin is a macromolecule that is classified as a nitrogen-containing polysaccharide. It is composed of N-acetylglucosamine units, which are derivatives of glucose that contain nitrogen.

2. **Chemical Composition**: The structure of chitin consists of long chains of N-acetylglucosamine, which is a modified form of glucose. The presence of nitrogen in its structure distinguishes it from other polysaccharides like cellulose.

3. **Occurrence in Nature**: Chitin is found in various biological structures:
- **Fungi**: It is a key component of the cell walls of fungi, providing structural support and protection.
- **Insects**: Chitin forms the exoskeleton of many insects, contributing to their rigidity and protection against environmental factors.
- **Cephalopods**: In cephalopods (like squids), chitin is part of their internal shell structure.
- **Birds**: The beaks of birds are also composed of chitin, showcasing its presence in various animal forms.

4. **Importance of Chitin**: Chitin plays a crucial role in the structural integrity of organisms that possess it. It provides strength and protection, making it essential for the survival of fungi, insects, and certain marine animals.

5. **Conclusion**: Therefore, chitin can be defined as a nitrogen-containing polysaccharide that is integral to the structure of fungi, the exoskeletons of insects, and various other biological entities.

**Final Answer**: Chitin is a nitrogen-containing polysaccharide.

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