Answer :
Final answer:
The hormone cholecystokinin (CCK) stimulates the release of enzyme-rich pancreatic juice, which is essential for the digestion of proteins and fats in the small intestine.
Explanation:
When proteins and fats enter the duodenum, they stimulate the secretion of CCK. This hormone then prompts the acinar cells of the pancreas to secrete enzymes that are crucial for digestion.
In addition to this, CCK works alongside another hormone called secretin, which is released in response to the acidity of chyme entering the duodenum from the stomach.
Secretin primarily stimulates the duct cells to release bicarbonate-rich pancreatic juice to neutralize the acid, thus creating an optimal environment for the action of pancreatic enzymes.