Herbivorous animals can digest celulose because

Options

A. they have large alimentary canal
B. Bacteria present in their rumen help in the digestion of cellulose
C. Gastric juice has a digestive enzyme for cellulose digestion
D. their molar and premolar teeth can crush and grind the food

Answer

### Step-by-Step Solution:

1. **Understanding Herbivorous Animals**:
- Herbivorous animals are those that primarily consume plant-based materials, such as grasses and leaves. This diet is rich in cellulose, a complex carbohydrate found in the cell walls of plants.

2. **Role of Cellulose**:
- Cellulose is a tough and fibrous substance that is difficult to digest for many animals. It requires specific enzymes to break it down into simpler sugars that can be absorbed and utilized by the body.

3. **Digestive System of Herbivores**:
- Herbivores have a specialized digestive system that includes a large alimentary canal. However, the key factor in their ability to digest cellulose is not just the size of their digestive tract.

4. **Rumen and Microbial Action**:
- In ruminants (like cows), the first compartment of their stomach is called the rumen. The rumen contains a rich population of microorganisms, including bacteria and protozoa, that play a crucial role in breaking down cellulose.

5. **Bacterial Digestion**:
- The bacteria present in the rumen produce enzymes that can effectively break down cellulose into simpler compounds. This microbial fermentation process allows herbivores to extract nutrients from plant material that they would otherwise be unable to digest.

6. **Conclusion**:
- Therefore, the primary reason herbivorous animals can digest cellulose is due to the bacteria present in their rumen, which assist in the fermentation and breakdown of cellulose.

### Final Answer:
Herbivorous animals can digest cellulose because of the bacteria present in their rumen that help in the digestion of cellulose.

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