HCl acts on the following to convert it into active form

Options

A. pepsin
B. trypsin
C. chymotrypsinogen
D. pepsinogen

Explanation

**Step-by-Step Solution:**

1. **Understanding the Role of HCl:**
- Hydrochloric acid (HCl) is secreted in the stomach and plays a crucial role in digestion. It creates an acidic environment that is necessary for the activation of certain digestive enzymes.

2. **Identifying the Inactive Form of Enzyme:**
- Among the various digestive enzymes, pepsinogen is known to be an inactive precursor (zymogen) of the active enzyme pepsin.

3. **Conversion Process:**
- When pepsinogen is exposed to the acidic environment created by HCl in the stomach, it undergoes a conformational change and is converted into its active form, pepsin.

4. **Function of Pepsin:**
- Pepsin is an active enzyme that helps in the digestion of proteins by breaking them down into smaller peptides.

5. **Conclusion:**
- Therefore, the answer to the question is that HCl acts on pepsinogen to convert it into its active form, pepsin.

**Final Answer:**
HCl acts on pepsinogen to convert it into its active form, pepsin.

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