Gastric acid is produced by specialized cells in the stomach lining called parietal cells.
The Location of Parietal Cells
- Parietal cells are primarily located in the proximal two-thirds (body) of the stomach. This region is crucial for the secretion of gastric acid.
Role of Gastric Acid
Gastric acid plays multiple essential roles in the digestion process:
-
Optimal pH for Digestive Enzymes: It creates an acidic environment, which is the optimal pH for the function of two key digestive enzymes:
- Pepsin, which breaks down proteins.
- Gastric lipase, which digests fats.
-
Stimulates Pancreatic Bicarbonate Secretion: Gastric acid triggers the release of bicarbonate from the pancreas. This bicarbonate is essential for neutralizing stomach acid as the partially digested food (chyme) enters the small intestine.
| Component | Function |
|---|---|
| Parietal Cells | Secrete Gastric Acid |
| Gastric Acid | Creates optimal pH for pepsin and gastric lipase activity |
| Pepsin | Breaks down proteins |
| Gastric Lipase | Digests fats |
| Pancreatic Bicarbonate | Neutralizes stomach acid in the small intestine |
In summary, gastric acid production involves the secretion from parietal cells located in the body of the stomach, which then creates an environment ideal for specific digestive enzymes and further supports the digestive process by stimulating pancreatic bicarbonate secretion.
