1, storage of bile: a hungry person (i.e. non-digestive period), bile is stored in the gallbladder, when digestion needs, and then discharged from the gallbladder, so the gallbladder is called “bile warehouse”. At the same time, it also plays the role of buffering the pressure of the bile duct. 2.Concentrated bile: Most of the water and electrolytes in the golden-yellow alkaline liver bile are absorbed by the mucous membrane of the gallbladder and returned to the blood, leaving the active ingredients in the bile stored in the gallbladder, which turns into brown or dark green weakly acidic bile. 3.Secretion of mucus: The gallbladder mucosa can secrete 20ml of thick mucus every day to protect the bile duct mucosa from erosion and dissolution of concentrated bile. 4, emptying: 3 to 5min after eating, food through the duodenum, stimulate the duodenal mucosa, produce a hormone called cholecystokinin, so that the gallbladder contraction, the gallbladder bile immediately into the duodenum, in order to help the digestion and absorption of fat, in the discharge of bile at the same time, but also the bacteria in the bile duct with bile. Generally speaking, the gallbladder can be emptied after half an hour of eating fat.