Enzyme pepsin acts upon food at a pH of about-

Options

A. 3 to split proteins
B. 2 to split carbohydrate
C. 7 to change protein into peptones
D. 2 to change proteins in amino acids

Answer

**Step-by-Step Solution:**

1. **Understanding Pepsin**: Pepsin is an enzyme that is primarily involved in the digestion of proteins. It is secreted by the stomach in an inactive form known as pepsinogen and is activated in the acidic environment of the stomach.

2. **pH Range for Pepsin Activity**: The optimal pH range for pepsin activity is between 1.5 to 3.5. This acidic environment is provided by gastric hydrochloric acid (HCl) present in the stomach.

3. **Function of Pepsin**: Pepsin acts on proteins and breaks them down into smaller peptides or peptones. This process is crucial for the subsequent digestion of proteins in the small intestine.

4. **Identifying the Correct pH**: Since the question asks for the pH at which pepsin acts upon food, we focus on the lower end of the pH range. The enzyme is most active at a pH around 3, which is still within the optimal range for its function.

5. **Conclusion**: Therefore, the enzyme pepsin acts upon food at a pH of about 3 to effectively split proteins.

**Final Answer**: The enzyme pepsin acts upon food at a pH of about 3 to split proteins.

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