Cholecystokinin is the secretion of

Options

A. Duodenum that causes contraction of gall bladder
B. Goblet cells of ileum stimulates secretion of succus entricus
C. Liver and controls secondary sexual characters
D. Stomach that stimulates pancreas to release juice

Answer

**Step-by-Step Solution:**

1. **Identify the Source of Cholecystokinin (CCK):**
Cholecystokinin is a hormone that is secreted by the cells located in the upper part of the small intestine, specifically the duodenum.

2. **Understand the Function of Cholecystokinin:**
The primary function of cholecystokinin is to stimulate the contraction of the gallbladder. This contraction helps in the release of bile, which is stored in the gallbladder.

3. **Recognize the Role of Bile:**
Bile plays a crucial role in the digestion of fats. It emulsifies fats, making them easier to digest by enzymes.

4. **Determine the Release Site:**
Cholecystokinin is released into the small intestine, where it acts to facilitate the digestion process by promoting bile release.

5. **Conclusion:**
Therefore, cholecystokinin is secreted by the cells of the duodenum in the upper small intestine.

**Final Answer:**
Cholecystokinin is the secretion of the duodenum.

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