Answer;
-Cholecystokinin
Explanation;
-Cholecystokinin is a hormone that is secreted by the mucosal epithelial cells of the upper small intestine (ileum). Its secretion is stimulated by the introduction of hydrochloric acid, amino acids, or fatty acids into the stomach or duodenum.
-Cholecystokinin stimulates the gallbladder to contract and release stored bile into the intestine. In other words it stimulates delivery into the small intestine of digestive enzymes from the pancreas and bile from the gallbladder.