Presence of fats and chyme in the food causes duodenum to produce this polypeptide hormone

Options

A. secretin
B. Gastric inhibitory peptide
C. Gastrin
D. Cholecystokinin

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:**
The question asks which polypeptide hormone is produced in the duodenum in response to the presence of fats and chyme in the food.

2. **Identifying Chyme:**
Chyme is the semi-fluid mass of partly digested food that is expelled from the stomach into the duodenum. It contains nutrients, digestive enzymes, and gastric juices.

3. **Role of the Duodenum:**
The duodenum is the first part of the small intestine, where the majority of chemical digestion occurs. It receives chyme from the stomach and bile from the liver, as well as pancreatic juices.

4. **Hormones Produced in the Duodenum:**
Several hormones are produced in the duodenum, including:
- Secretin
- Gastric inhibitory peptide (GIP)
- Gastrin
- Cholecystokinin (CCK)

5. **Functions of the Hormones:**
- **Secretin:** Regulates pancreatic bicarbonate secretion and gastric acid.
- **GIP:** Enhances insulin production and plays a role in lipid metabolism.
- **Gastrin:** Stimulates acid secretion in the stomach.
- **Cholecystokinin (CCK):** Stimulates the release of digestive enzymes from the pancreas and bile from the gallbladder, particularly in response to fats and proteins.

6. **Determining the Correct Hormone:**
Since the question specifies the presence of fats and chyme, the hormone that is specifically stimulated by fats in the duodenum is **Cholecystokinin (CCK)**. CCK is released when fats are present and plays a crucial role in digestion by promoting the release of digestive enzymes.

7. **Conclusion:**
Therefore, the polypeptide hormone produced in the duodenum in response to the presence of fats and chyme is **Cholecystokinin (CCK)**.

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