Cells of the pancreas is not digested by their own enzymes because :

Options

A. enzymes are secreted in inactive form
B. cells are lined by mucous membrane
C. enzymes are released only when needed
D. None of the above

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:**
The question asks why the cells of the pancreas are not digested by their own enzymes. This is a fundamental concept in physiology, particularly related to the digestive system.

2. **Role of Pancreatic Enzymes:**
The pancreas secretes digestive enzymes that are crucial for breaking down food in the small intestine. However, these enzymes must be in an active form to function properly.

3. **Inactivated Form of Enzymes:**
The enzymes produced by the pancreas are initially secreted in an inactive form. For example, trypsinogen is an inactive precursor of the enzyme trypsin.

4. **Activation of Enzymes:**
These inactive enzymes are activated when they come into contact with specific activators. In the case of trypsinogen, it is activated by enterokinase, an enzyme present in the intestinal mucosa.

5. **Protection of Pancreatic Cells:**
Since the enzymes are secreted in an inactive form, they cannot digest the pancreatic cells themselves. This mechanism protects the pancreas from self-digestion.

6. **Conclusion:**
Therefore, the reason the cells of the pancreas are not digested by their own enzymes is that these enzymes are secreted in an inactive form.

7. **Final Answer:**
The correct answer is that the cells of the pancreas are not digested by their own enzymes because the enzymes are secreted in an inactive form.

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