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 Pancreas Function**: The pancreas is an organ that plays a crucial role in digestion by secreting digestive enzymes, particularly proteases that break down proteins.

2. **Identifying the Enzymes**: The pancreas secretes three main protein-digesting enzymes:
- Trypsinogen (inactive form)
- Chymotrypsinogen (inactive form)
- Procarboxypeptidase (inactive form)

3. **Activation of Enzymes**: These enzymes are secreted in their inactive forms to prevent them from digesting the proteins in the pancreas itself.
- Trypsinogen is converted to its active form, trypsin, by the enzyme enterokinase.
- Trypsin then activates chymotrypsinogen to chymotrypsin and procarboxypeptidase to carboxypeptidase.

4. **Site of Action**: The activation of these enzymes occurs only when they reach the small intestine, which is their site of action for digesting proteins.

5. **Conclusion**: The cells of the pancreas are not digested by their own enzymes because these enzymes are secreted in inactive forms and are activated only when they reach their specific site of action.

**Final Answer**: Cells of the pancreas are not digested by their own enzymes because they are secreted in inactive forms and activated only in the small intestine.

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