Which is different ?

Options

A. Gastrin
B. Secretin
C. Ptyalin
D. Glucagon

Answer

To determine which option is different among gastrin, secretin, ptyalin, and glucagon, we can analyze each of them based on their classification and function.

### Step-by-Step Solution:

1. **Identify Each Option**:
- **Gastrin**: This is a hormone produced by G-cells in the stomach. Its primary function is to stimulate the secretion of hydrochloric acid (HCl) in the stomach.
- **Secretin**: This is also a hormone, produced in the duodenum (the first part of the small intestine). It helps regulate the pH of the intestinal contents by stimulating the pancreas to release bicarbonate.
- **Ptyalin**: This is an enzyme, also known as salivary amylase. It is found in saliva and is responsible for the initial digestion of carbohydrates in the mouth.
- **Glucagon**: This is another hormone, secreted by the alpha cells of the pancreas. Its main role is to increase blood glucose levels by stimulating the liver to convert stored glycogen into glucose.

2. **Classify the Options**:
- Gastrin, secretin, and glucagon are all hormones.
- Ptyalin is an enzyme.

3. **Determine the Odd One Out**:
- Since gastrin, secretin, and glucagon are hormones and ptyalin is an enzyme, ptyalin is the only one that does not belong to the same category as the others.

4. **Conclusion**:
- The option that is different from the others is **ptyalin** (option 3).

### Final Answer:
The odd one out is **ptyalin**.

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