Glycogen is a homopolymer made of:

Options

A. Glucose units
B. Galactose units
C. Ribose units
D. Aminoacids

Answer

### Step-by-Step Solution:

1. **Understanding Glycogen**: Glycogen is a polysaccharide that serves as a form of energy storage in animals and fungi. It is primarily found in the liver and muscle tissues.

2. **Composition of Glycogen**: Glycogen is classified as a homopolymer, which means it is made up of repeating units of the same type of monomer. In the case of glycogen, these monomer units are glucose.

3. **Structure of Glycogen**: Glycogen consists of long chains of glucose molecules linked together. The glucose units are connected primarily through glycosidic bonds. Specifically, glycogen has:
- **1,4-glycosidic bonds**: These bonds connect the glucose molecules linearly.
- **1,6-glycosidic bonds**: These bonds create branches in the glycogen structure.

4. **Branching in Glycogen**: Glycogen is highly branched, with branches occurring approximately every 10 glucose units. This branching allows for rapid release of glucose when energy is needed.

5. **Conclusion**: Since glycogen is made entirely of glucose units, we can conclude that glycogen is a homopolymer made of glucose.

### Final Answer:
Glycogen is a homopolymer made of glucose.

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