Question

Secretin and cholecystokinin are digestive hormones. They are secreted in

• A. Pyloric stomach
• B. Duodenum
• C. Ileum
• D. Oesophagus

Answer 1

The Correct Option is B

The question is asking about the site of secretion for two specific digestive hormones: secretin and cholecystokinin.

1. **Understanding the Hormones:** - **Secretin**: This hormone is primarily responsible for stimulating the pancreas to secrete bicarbonate, which neutralizes stomach acid in the small intestine. - **Cholecystokinin (CCK)**: This hormone triggers the gallbladder to release bile and the pancreas to secrete its enzymes, aiding in the digestion of fats and proteins.

2. **Site of Hormone Secretion:**
Both hormones, secretin and cholecystokinin, are secreted by the mucosal epithelial cells lining the **duodenum**, which is the first section of the small intestine immediately after the stomach.

3. **Evaluating the options:**
- **Pyloric Stomach:** This part is responsible for transferring food to the duodenum but not for secreting these hormones. - **Duodenum:** Correct, as both secretin and cholecystokinin are indeed secreted here. - **Ileum:** This is the last part of the small intestine and is primarily involved in nutrient absorption but not in the secretion of these hormones. - **Oesophagus:** This part of the digestive system is responsible for moving swallowed food to the stomach and does not secrete these hormones.

4. **Conclusion:**
The duodenum is the correct answer as it serves as the site for the secretion of secretin and cholecystokinin. Therefore, the correct option is: Duodenum.