Cholecystokinin and secretin are secreted by

Options

A. Stomach
B. Ileum
C. Duodenum
D. Colon

Answer

To answer the question "Cholecystokinin and secretin are secreted by," we will follow these steps:

### Step 1: Identify the hormones
Cholecystokinin (CCK) and secretin are both hormones involved in the digestive process.

### Step 2: Locate the source of secretion
These hormones are secreted by specific glands in the digestive system. Cholecystokinin is primarily secreted by I cells in the duodenum, while secretin is secreted by S cells in the same region.

### Step 3: Understand the function of these hormones
Cholecystokinin stimulates the gallbladder to contract and release bile, while secretin stimulates the pancreas to release bicarbonate, which neutralizes stomach acid in the small intestine.

### Step 4: Identify the organ
Both hormones are secreted in the duodenum, which is the first part of the small intestine.

### Step 5: Eliminate incorrect options
- **Stomach**: This is incorrect as the stomach does not secrete these hormones.
- **Avium**: This is not a recognized part of the digestive system in this context.
- **Colon**: This is also incorrect as the colon does not secrete these hormones.

### Conclusion
The correct answer is the **duodenum**.

### Final Answer
Cholecystokinin and secretin are secreted by the **duodenum**.

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