The secretin promotes the release of

Options

A. HCI and sodium carbonate ions
B. HCI and bicarbonate ions in gastric juice
C. Water and bicarbonate ions in pancreatic juice
D. Pancreatic enzymes and mucus

Answer

**Step-by-Step Solution:**

1. **Understanding Secretin**: Secretin is a hormone that is produced in the S cells of the small intestine. It plays a crucial role in the digestive process.

2. **Function of Secretin**: The primary function of secretin is to regulate the pH of the small intestine by promoting the release of bicarbonate ions.

3. **Release of Bicarbonate**: When secretin is released, it stimulates the pancreas to secrete a bicarbonate-rich fluid. This bicarbonate helps neutralize the acidic chyme that comes from the stomach into the small intestine.

4. **Effect on Gastric HCl**: Secretin also has an inhibitory effect on gastric acid (HCl) secretion. This means that while it promotes bicarbonate release, it decreases the secretion of gastric acid.

5. **Conclusion**: Based on the functions of secretin, we can conclude that it promotes the release of water and bicarbonate ions in pancreatic juice. This is important for maintaining the proper pH in the small intestine for optimal enzyme activity.

6. **Final Answer**: Therefore, the correct answer to the question "The secretin promotes the release of" is **water and bicarbonate ions in pancreatic juice**.

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