Rennin enzyme occurs in the gastric juice of

Options

A. Calf
B. Human adults
C. Human infants
D. Both A and C

Answer

**Step-by-Step Solution:**

1. **Understanding Rennin**: Rennin is an enzyme that is primarily involved in the coagulation of milk. It helps in curdling milk, which is essential for digestion in young mammals.

2. **Identifying Sources of Rennin**: Rennin is produced in the stomachs of certain animals, particularly in calves and human infants. In calves, it plays a crucial role in digesting their mother's milk.

3. **Analyzing the Options**:
- **Option A: Calf**: This is correct because rennin is present in the gastric juice of calves to help digest milk.
- **Option B: Human Adult**: This is incorrect as rennin is not present in significant amounts in adults; instead, adults primarily have pepsin for protein digestion.
- **Option C: Human Infants**: This is correct as rennin is present in the gastric juice of human infants to aid in milk digestion.

4. **Conclusion**: The correct answers are both A (Calf) and C (Human Infants) since rennin is present in the gastric juice of both.

**Final Answer**: Rennin enzyme occurs in the gastric juice of calves and human infants.

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