Protection of intestinal mucosa as well as alkaline medium (pH = 7.8) for enzymatic actions in small intestine is provided by

Options

A. Mucus of intestinal juice
B. Bicarbonate from pancreas
C. Mucus and bicarbonates from Brunner's gland/ duodenal glands
D. All

Answer

To solve the question regarding the protection of intestinal mucosa and the provision of an alkaline medium (pH = 7.8) for enzymatic actions in the small intestine, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Role of pH in the Small Intestine**:
- The small intestine requires an alkaline medium for optimal enzymatic activity, particularly for pancreatic enzymes that are secreted into the small intestine.

2. **Identifying the pH Level**:
- The pH in the small intestine is approximately 7.8, which is slightly alkaline. This is essential for the proper functioning of digestive enzymes.

3. **Sources of Alkalinity**:
- The alkalinity in the small intestine is primarily provided by bicarbonate ions (HCO3-) that are secreted by the pancreas. This bicarbonate neutralizes the acidic chyme coming from the stomach.

4. **Protection of Intestinal Mucosa**:
- The intestinal mucosa is protected by mucus, which is secreted by the goblet cells in the intestinal lining. This mucus not only provides a protective barrier but also contributes to the alkaline environment.

5. **Additional Sources of Mucus and Bicarbonate**:
- The duodenum, which is the first part of the small intestine, also secretes mucus and bicarbonate through the Brunner's glands. This further enhances the protective and alkaline environment necessary for digestion.

6. **Conclusion**:
- Therefore, the protection of the intestinal mucosa and the provision of an alkaline medium in the small intestine is achieved through the secretion of mucus and bicarbonate from the pancreas and Brunner's glands.

### Final Answer:
The protection of intestinal mucosa as well as the alkaline medium (pH = 7.8) for enzymatic actions in the small intestine is provided by mucus and bicarbonate from the pancreas and Brunner's glands.

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