Cellulose present in the food of grazing animals is

Options

A. Digested by intestinal bacteria
B. Digested by animals itself
C. Digested partly by the animals and partly by bacteria
D. Passed out undigested.

Answer

### Step-by-Step Solution:

1. **Understanding the Diet of Grazing Animals**:
- Grazing animals, also known as ruminants (like cattle, sheep, and deer), primarily consume grasses which are high in cellulose.

2. **Role of Cellulose**:
- Cellulose is a complex carbohydrate that is difficult for many animals to digest due to the lack of specific enzymes.

3. **Symbiotic Relationship**:
- Ruminants have a symbiotic relationship with certain bacteria in their intestines. These bacteria have the necessary enzymes to break down cellulose.

4. **Digestion Process**:
- When grazing animals consume grass, the cellulose is not digested by the animals themselves but rather by the symbiotic bacteria present in their digestive system.

5. **Evaluating the Options**:
- **Option A**: "Cellulose present in the food of grazing animals is digested by intestinal bacteria." - This is correct.
- **Option B**: "Digested by animals itself." - Incorrect, as ruminants lack the enzymes to digest cellulose.
- **Option C**: "Digested partially by the animals and partially by bacteria." - Incorrect, as cellulose is fully digested by bacteria.
- **Option D**: "Passed out undigested." - Incorrect, as cellulose is digested by bacteria in ruminants, unlike in humans where it may pass undigested.

6. **Conclusion**:
- The correct answer is **Option A**: Cellulose present in the food of grazing animals is digested by intestinal bacteria.