The optimum pH for pepsin is

Options

A. 11
B. `5-6`
C. `1.6-2.4`
D. `4-7`

Answer

To determine the optimum pH for pepsin, follow these steps:

1. **Understand Pepsin's Role**: Recognize that pepsin is a protein-digesting enzyme. It is crucial to know its function in the digestive system.

2. **Identify the Location of Action**: Note that pepsin is secreted in the stomach. This is important because the environment in which an enzyme functions can greatly affect its activity.

3. **Consider the pH Environment**: Enzymes often have specific pH ranges in which they are most active. For pepsin, it is essential to understand that it requires an acidic medium for optimal activity.

4. **Know the Source of Acidity**: The acidity in the stomach is primarily due to hydrochloric acid (HCl). This acid creates the necessary environment for pepsin to function effectively.

5. **Determine the Optimum pH Range**: The pH in the stomach, due to the presence of hydrochloric acid, typically ranges from 1.6 to 2.4. This is the range in which pepsin is most active.

6. **Select the Correct Answer**: Based on the information gathered, the optimum pH for pepsin is 1.6 to 2.4.

### Final Answer:
The optimum pH for pepsin is **1.6 to 2.4**.

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