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What role does the gallbladder play in digestion?

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Diagram of the human digestive system viewed from the front, showing and labeling organs including the mouth, teeth, tongue, salivary glands, pharynx, esophagus, liver, stomach, gallbladder, pancreas, large intestine, small intestine, appendix, rectum, and anus. — digestion The human digestive system as seen from the front.

The gallbladder serves as a muscular, pear-shaped sac that plays a vital role in the digestion of fats by storing and concentrating bile.12

Produced by the liver, bile is a fluid containing bile acids and salts that act as detergents to emulsify fat, preparing it for further breakdown by enzymes. When the small intestine is empty, the sphincter of Oddi remains closed, forcing bile to accumulate and flow into the gallbladder. Within this organ, the mucous membrane absorbs water and inorganic salts, concentrating the bile to several times its original strength.12

When food enters the duodenum, the hormone cholecystokinin and the vagus nerve stimulate the gallbladder to contract. This action releases the concentrated bile through the bile duct into the small intestine, where it facilitates the digestion of fats. Despite this function, the gallbladder can be surgically removed without serious long-term effects on digestion.12