Trypsinogen is converted into active trypsin by the action of

Options

A. Cholecystokinin
B. Enterocrinin
C. Enterokinase
D. Secretin

Answer

To answer the question "Trypsinogen is converted into active trypsin by the action of," we need to identify the correct enzyme responsible for this conversion from the given options.

### Step-by-Step Solution:

1. **Understanding Trypsinogen**:
- Trypsinogen is an inactive precursor (zymogen) of the enzyme trypsin, which is produced by the pancreas.

2. **Role of Enterokinase**:
- Enterokinase, also known as enteropeptidase, is an enzyme secreted by the intestinal mucosa. Its primary function is to activate trypsinogen into trypsin.

3. **Examining the Options**:
- **Cholecystokinin**: This hormone stimulates the contraction of the gallbladder and the secretion of pancreatic juices but does not activate trypsinogen.
- **Enterocrinin**: This hormone stimulates the release of alkaline mucus from the intestinal glands but does not activate trypsinogen.
- **Secretin**: This hormone is involved in regulating water homeostasis and the secretion of pancreatic juices but does not activate trypsinogen.

4. **Conclusion**:
- The only enzyme listed that specifically activates trypsinogen into trypsin is **Enterokinase**. Therefore, the correct answer is **Enterokinase**.

### Final Answer:
Trypsinogen is converted into active trypsin by the action of **Enterokinase**.

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