Ptyalin cannot work in stomach, because it becomes-

Options

A. Inactive due to HCI
B. Inactive due to Renin
C. Inactive due to Pepsin
D. None of these

Answer

**Step-by-Step Solution:**

1. **Understanding Ptyalin:** Ptyalin, also known as salivary amylase, is an enzyme produced by the salivary glands. Its primary function is to break down starch into simpler sugars during the initial phase of digestion in the mouth.

2. **Optimal pH for Ptyalin Activity:** Ptyalin operates effectively in a slightly acidic to neutral pH range, typically between 6.35 and 6.85. This pH range is conducive for its enzymatic activity.

3. **Entry into the Stomach:** When food is ingested, it travels from the mouth to the stomach, carrying with it the saliva that contains Ptyalin.

4. **Stomach Environment:** The stomach has a highly acidic environment due to the secretion of hydrochloric acid (HCl). The pH in the stomach can drop to around 1.5 to 3.5, which is much lower than the optimal pH for Ptyalin.

5. **Inactivation of Ptyalin:** When Ptyalin enters the stomach, the highly acidic environment (due to HCl) causes the enzyme to become inactive. Enzymes are sensitive to pH changes, and when the pH falls outside their optimal range, they can denature or lose their functional shape.

6. **Conclusion:** Therefore, Ptyalin cannot work in the stomach because it becomes inactive due to the presence of hydrochloric acid (HCl).

**Final Answer:** Ptyalin cannot work in the stomach because it becomes inactive due to HCl.

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