Mark the odd one

Options

A. Gastrin
B. Trypsin
C. Secretin
D. Enterocrinin

Answer

To solve the question "Mark the odd one," we need to analyze the given options: gastrin, trypsin, secretin, and anterocrinone. We will identify which one does not belong with the others based on their functions and locations in the digestive system.

### Step-by-Step Solution:

1. **Identify the Functions of Each Option**:
- **Gastrin**: This is a hormone that stimulates the secretion of gastric acid in the stomach. It is produced by G cells in the gastric mucosa.
- **Trypsin**: This is an enzyme that is secreted by the pancreas into the small intestine. It helps in the digestion of proteins.
- **Secretin**: This is a hormone that is secreted by S cells in the duodenum (part of the small intestine) and regulates water homeostasis and the secretion of digestive fluids.
- **Anterocrinone**: This is a hormone that affects the duodenum and is involved in the secretion of mucus by the submucosal glands in the small intestine.

2. **Determine the Location of Action**:
- **Gastrin** acts in the stomach.
- **Trypsin**, **Secretin**, and **Anterocrinone** all act in the small intestine.

3. **Identify the Odd One Out**:
- Since gastrin is the only option that acts in the stomach and not in the small intestine, it is the odd one out.

4. **Conclusion**:
- Therefore, the correct answer is **Gastrin** (Option 1).

### Final Answer:
**Gastrin** is the odd one out.

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