Abdominal Ultrasound Practice Test 2025 – Complete Exam Prep

Cholecystokinin (CCK) is the hormone released after the ingestion of a fatty meal that plays a crucial role in digestion. When fats enter the small intestine, CCK is secreted by the cells of the duodenum. Its primary functions include stimulating the contraction of the gallbladder, which facilitates the release of bile into the intestine, essential for the emulsification and absorption of fats.

In addition to gallbladder contraction, CCK also promotes the secretion of digestive enzymes from the pancreas, enhancing the digestive process. The timing of this response is critical, as the presence of fats necessitates the efficient breakdown and absorption of dietary fats in the gastrointestinal tract. By directly stimulating the gallbladder, CCK ensures that bile is readily available when needed.

The other hormones listed have different roles in the digestive system. Insulin primarily manages blood glucose levels and facilitates cellular uptake of glucose. Gastrin stimulates gastric acid secretion in response to food intake, particularly proteins, but does not specifically affect gallbladder contraction. Secretin plays a role in regulating the pH of the small intestine by stimulating pancreatic bicarbonate secretion but does not directly influence gallbladder activity. This distinct role of CCK as a gallbladder contractor