Question

The contraction of gall bladder is due to

• A. Enterogastrone
• B. Cholecystokinin
• C. Secretin
• D. Gastrin

Answer 1

The correct option is B

Cholecystokinin

The correct option is B

Explanation of the correct option:

1. Food increases the creation of the hormone cholecystokinin in the small intestine when it enters the digestive tract.
2. When cholecystokinin is released, the gallbladder contracts and discharges the stored bile into the common bile duct, which eventually empties its contents into the duodenum.
3. Bile becomes concentrated as water in the gallbladder during storage, and certain electrolytes are taken from it.
4. Bile also aids in the elimination of bilirubin, a byproduct of hemoglobin metabolism.
5. Excess bilirubin can lead to gallbladder stones, which are dangerous to health.

Explanation of the incorrect options:

Option A:

1. Enterogastrone is a hormone produced by the duodenal mucosa in response to fatty foods in the stomach or small intestine.
2. It is also hypothesized to be released in response to carbohydrates and proteins in the intestine.

Option C:

1. Secretin's primary job is to neutralize the pH in the duodenum, allowing pancreatic digesting enzymes (such as pancreatic amylase and pancreatic lipase) to work optimally.
2. Hormones are secreted into the circulation by the duodenum to increase liver and pancreatic production (particularly in reaction to acidity).

Option D:

1. Gastrin is a hormone that facilitates gastric motility by stimulating the release of gastric acid (HCl) by the parietal cells of the stomach.
2. It is found in G cells of the antrum and duodenum of the stomach.

Final Answer: The contraction of the gall bladder is due to cholecystokinin.