The gallbladder contracts and expels bile into the duodenum

The gallbladder contracts and expels bile into the duodenum after a meal. The major factor bringing about this contraction is:

a) activation of the sympathetic nerve supplying the gallbladder.

b) an increased concentration of bile salts in the gallbladder bile.

c) a “downward” movement of the liver which increases the pressure around the gallbladder.

d) increased release of cholecystokinin.

e) increased activation of smooth muscle in the sphincter of Oddi.

Solution

Ans:- Gallbladder is a small hollow sac attached to the lower part of liver .Its main function is to store bile and release it in the intestine for digestion of food .Contraction of gallbladder is a normal physiological process. It occurs when we eat food or after a meal especially fatty foods.The bile released from the gall bladder helps in thedigestion of fats present in the food. It is a physiological process .After we eat a meal, a message is sent to the gallbladder to contract so that the stored concentrated bile is released in the intestine through the bile duct. The gall bladder after emptying of the bile becomes small and contracted till it is filled again with bile produced by liver.

So the correct answer is (b) an increased concentration of bile salt in the gallbladder bile.