Enzyme trypsinogen is changed to trypsin by

Options

A. Gastrin
B. Enterogastrone
C. Enterokinase
D. Secretin

Answer

To solve the question "Enzyme trypsinogen is changed to trypsin by", we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Trypsinogen and Trypsin**:
- Trypsinogen is an inactive precursor (zymogen) of the enzyme trypsin. It is produced by the pancreas and released into the small intestine.

2. **Activation Process**:
- Enzymes like trypsinogen are secreted in an inactive form to prevent them from digesting proteins in the cells that produce them. They need to be activated to perform their function.

3. **Identifying the Activating Enzyme**:
- The activation of trypsinogen to trypsin occurs in the small intestine. The enzyme responsible for this conversion is enterokinase (also known as enteropeptidase).

4. **Evaluating the Options**:
- **Gastrin**: This is a hormone that stimulates gastric acid secretion but does not activate trypsinogen.
- **Anterogastron**: This is a hormone related to the gastrointestinal tract but is not involved in the activation of trypsinogen.
- **Enterokinase**: This is the correct enzyme that activates trypsinogen into trypsin.
- **Secretin**: This hormone regulates water homeostasis and stimulates the pancreas but does not activate trypsinogen.

5. **Conclusion**:
- The correct answer to the question is **enterokinase**, as it is the enzyme that converts trypsinogen into the active enzyme trypsin.

### Final Answer:
Trypsinogen is changed to trypsin by **enterokinase**.

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