Cellulose is

Options

A. simple sugar
B. glycogen
C. carbohydrate
D. protein

Explanation

**Step-by-Step Text Solution:**

1. **Definition of Cellulose**:
Cellulose is a complex carbohydrate, specifically a polysaccharide, which consists of long chains of glucose molecules linked together. It is not a simple sugar but rather a structural component found in the cell walls of plants.

2. **Composition**:
Cellulose is made up of hundreds to thousands of carbon (C), hydrogen (H), and oxygen (O) atoms. The general formula for cellulose can be represented as (C6H10O5)n, where 'n' indicates the number of repeating glucose units.

3. **Function in Plants**:
The primary function of cellulose is to provide structural support to plant cells. It helps maintain the rigidity and upright position of plants, allowing them to grow tall and withstand various environmental pressures.

4. **Structure of Cellulose**:
The structure of cellulose is characterized by linear chains of β-D-glucose units linked by β-1,4-glycosidic bonds. This means that the hydroxyl group (OH) on the first carbon of one glucose unit is linked to the fourth carbon of the next glucose unit in an alternating manner.

5. **Linkage and Configuration**:
The β-1,4 linkage in cellulose results in a straight, unbranched chain, which allows the molecules to pack tightly together, forming strong fibers. This structural arrangement is crucial for its role in providing strength to plant cell walls.

6. **Conclusion**:
In summary, cellulose is a vital polysaccharide in plants, composed of glucose units linked by β-1,4-glycosidic bonds, contributing to the structural integrity and rigidity of plant cells.

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