Which of the following is a heteropolysaccharide?

Options

A. Peptidoglycan
B. Chitin
C. Cellulose
D. Starch

Answer

To determine which of the following is a heteropolysaccharide, we need to understand the definition of heteropolysaccharides and analyze the given options.

### Step-by-Step Solution:

1. **Understand Heteropolysaccharides**:
- Heteropolysaccharides are polysaccharides that are composed of two or more different types of monosaccharide units. This means they are made from different kinds of sugar molecules.

2. **Analyze the Options**:
- **Starch**: Starch is a polysaccharide that consists of amylose and amylopectin, both of which are polymers made entirely of glucose units. Therefore, starch is a homopolysaccharide.
- **Cellulose**: Cellulose is also a homopolysaccharide, as it is composed solely of glucose units linked together.
- **Chitin**: Chitin is a homopolysaccharide made up of N-acetylglucosamine units, which are also similar in structure and composition.
- **Peptidoglycan**: Peptidoglycan is composed of different types of monomer units, specifically N-acetylglucosamine and N-acetylmuramic acid. This makes it a heteropolysaccharide.

3. **Conclusion**:
- Among the options provided, the only heteropolysaccharide is **Peptidoglycan**.

### Final Answer:
**Peptidoglycan is the heteropolysaccharide.**

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