A fibrous polysachharide is

Options

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

Answer

To answer the question "A fibrous polysaccharide is," we will analyze the options provided and identify which one fits the definition of a fibrous polysaccharide.

### Step-by-Step Solution:

1. **Understanding Polysaccharides**:
- Polysaccharides are complex carbohydrates made up of long chains of monosaccharide units (simple sugars). They can be classified into different types based on their structure and function.

2. **Identifying the Options**:
- The options given are:
- A. Glycogen
- B. Starch
- C. Cellulose
- D. Collagen

3. **Analyzing Each Option**:
- **Glycogen**: This is a storage polysaccharide found in animals. It is highly branched and not fibrous.
- **Starch**: This is a storage polysaccharide found in plants. It consists of amylose and amylopectin, which are not fibrous in structure.
- **Cellulose**: This is a structural polysaccharide that forms the cell wall of plants. It consists of long chains of glucose units linked by beta-1,4-glycosidic bonds, giving it a fibrous structure.
- **Collagen**: This is a protein, not a polysaccharide, and while it has a fibrous structure, it does not fit the definition of a polysaccharide.

4. **Conclusion**:
- Among the options, **cellulose** is the only fibrous polysaccharide. It provides structural support to plant cell walls and is characterized by its long, fibrous chains.

### Final Answer:
A fibrous polysaccharide is **cellulose**.

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