In man cellulose is digested in

Options

A. The caecum
B. The colon
C. The appendix
D. Not digested at all

Explanation

### Step-by-Step Solution:

1. **Understanding Cellulose**:
- Cellulose is a complex carbohydrate, specifically a polysaccharide, composed of β-glucose monomer units. It is a major component of plant cell walls.

2. **Enzyme Requirement for Digestion**:
- To digest cellulose, an enzyme called cellulase is required. This enzyme breaks down the β-glucose bonds in cellulose.

3. **Human Digestive System**:
- In humans, the digestive system lacks the enzyme cellulase. This means that humans are unable to break down cellulose into simpler sugars.

4. **Consequences of Lack of Digestion**:
- Since cellulose cannot be digested, it passes through the human digestive tract undigested. It is often referred to as dietary fiber or roughage.

5. **Conclusion**:
- Therefore, in humans, cellulose is not digested at all. The correct answer to the question is that cellulose is not digested in the human body.

### Final Answer:
Cellulose is not digested at all in humans.

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