The monomer units of chitin and fungus cellulose are

Options

A. Mannitol
B. Acetyl glucosamine
C. Ascorbic acid
D. Glucuronic acid.

Answer

To determine the monomer units of chitin and fungus cellulose, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Chitin**:
- Chitin is a long-chain polymer primarily composed of N-acetylglucosamine (GlcNAc). It is derived from glucose and consists of repeating units of N-acetylglucosamine linked together.

2. **Identifying the Monomer**:
- The monomer unit of chitin is N-acetylglucosamine. This is a derivative of glucosamine, which is a modified form of glucose where an acetyl group is attached to the amino group.

3. **Understanding Fungus Cellulose**:
- Fungus cellulose, like chitin, also contains N-acetylglucosamine as its monomer unit. This is because the structure of fungus cellulose is similar to that of chitin, where the hydroxyl group in cellulose is replaced by an acetylamine group.

4. **Analyzing the Options**:
- The options given are:
- Mannitol
- Acetylglucosamine
- Ascorbic acid
- Glucuronic acid
- Among these, mannitol is a sugar alcohol and not related to chitin or cellulose. Ascorbic acid (Vitamin C) is an antioxidant and has no relation to these polymers. Glucuronic acid is a compound produced in the liver and is not a monomer of chitin or cellulose.

5. **Conclusion**:
- The only correct option that represents the monomer units of chitin and fungus cellulose is **N-acetylglucosamine**.

### Final Answer:
The monomer units of chitin and fungus cellulose are **N-acetylglucosamine**.

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