Which of the following is a heteropolymer ?

Options

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

Explanation

To determine which of the following is a heteropolymer, we need to understand the definition of a heteropolymer and analyze the options provided.

### Step-by-Step Solution:

1. **Understand the Definition of Heteropolymer**:
A heteropolymer is a type of polymer that is composed of different types of monomeric units. This means that the repeating units in the polymer chain are not identical.

2. **Analyze the Given Options**:
- **Cellulose**: This is a polymer made up of repeating units of beta-glucose. Since all the monomers are the same, cellulose is a homopolymer.
- **Peptidoglycan**: This polymer consists of alternating units of N-acetylglucosamine (NAG) and N-acetylmuramic acid (NAM). Since it contains two different types of monomers, peptidoglycan is a heteropolymer.
- **Starch**: Starch is composed of alpha-glucose units. Like cellulose, all the monomers are the same, making starch a homopolymer.
- **Glycogen**: Similar to starch, glycogen is also made up of alpha-glucose units, thus it is a homopolymer as well.

3. **Identify the Correct Answer**:
From the analysis, the only option that contains different types of monomers is peptidoglycan. Therefore, the correct answer to the question is **Peptidoglycan**.

### Final Answer:
**Peptidoglycan** is a heteropolymer.

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