Gastrointestinal Tract

The Gallbladder

The gallbladder is a small pear-shaped muscular sack that acts as a storage tank for bile. The bile is made in the liver by liver cells and is sent through tiny ducts or canals to the duodenum (small intestine) and to the gallbladder. The gallbladder stores the bile to have it available in larger quantities for secretion when a meal is eaten.

The ingestion of food and especially fats cause the release of a hormone, cholecystokinin, (CCK) which in turn signals the relaxation of the valve at the end of the common bile duct (the sphincter of oddi) which lets the bile enter the small intestine. It also signals the contraction of the gallbladder which squirts the concentrated liquid bile into the small intestine where it helps with the emulsification or breakdown of fats in the meal.