Among mammals, a significant role in the digestion of milk is played by:

Options

A. Rennin
B. Invertase
C. Amylase
D. Intestinal bacteria

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which substance plays a significant role in the digestion of milk among mammals.

2. **Identifying the Options**: The options provided are Renin, Invertase, Amylase, and Intestinal Bacteria.

3. **Analyzing Each Option**:
- **Renin**: This enzyme is secreted in the stomach of young mammals. It acts on milk proteins, specifically caseinogen, causing it to curdle and convert into casein. This process is crucial for the digestion of milk in young mammals.
- **Invertase**: This enzyme breaks down sucrose into glucose and fructose. It does not play a role in milk digestion.
- **Amylase**: This enzyme is responsible for breaking down starch into maltose. It is not involved in the digestion of milk proteins.
- **Intestinal Bacteria**: While some bacteria in the intestines produce vitamins, they do not digest milk proteins.

4. **Conclusion**: Based on the analysis, Renin is the enzyme that plays a significant role in the digestion of milk among mammals, particularly in young mammals.

5. **Final Answer**: The correct answer is Renin.

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