The presence of which substance in the duodenum stimulates the release of bile from the gallbladder?

The presence of triglycerides in the duodenum is a key factor in stimulating the release of bile from the gallbladder. When dietary fats, specifically triglycerides, enter the duodenum, they are detected by specialized cells that release the hormone cholecystokinin (CCK). CCK not only promotes the contraction of the gallbladder to release bile but also stimulates the pancreas to secrete digestive enzymes that further aid in the emulsification and digestion of fats.

Bile, which contains bile salts, is essential for the digestion and absorption of dietary lipids. The bile salts act to emulsify fats, increasing their surface area so that digestive enzymes can more effectively break them down. This process is crucial for the absorption of fatty acids and monoglycerides in the intestine.

In contrast, while glucose, proteins, and vitamins do play roles in digestion and nutrient absorption, it is specifically the presence of triglycerides that directly triggers this response related to bile release.