Secretin acts on the

Options

A. liver
B. stomach
C. pancreas
D. small intestine

Answer

**Step-by-Step Solution:**

1. **Understanding Secretin**: Secretin is a peptide hormone that plays a crucial role in the digestive process. It is important to know that it is produced by specific cells in the duodenum, which is the first part of the small intestine.

2. **Source of Secretin**: Secretin is produced by S cells located in the intestinal glands of the duodenum. This information is essential as it helps us identify where secretin originates.

3. **Target Organ of Secretin**: The primary target of secretin is the pancreas. It stimulates the pancreas to release bicarbonate, which helps neutralize stomach acid in the small intestine.

4. **Functions of Secretin**: Besides acting on the pancreas, secretin also has other functions, such as regulating gastric acid secretion and stimulating bile production in the liver. However, its principal action is on the pancreas.

5. **Evaluating Options**: Given the options (liver, stomach, pancreas, small intestine), we need to identify which organ secretin primarily acts upon. Since we established that the pancreas is the main target, we can conclude that the correct answer is the pancreas.

6. **Final Answer**: Therefore, secretin acts on the pancreas.

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