What does secretin do?

What does secretin do?

• A. Stimulates gallbladder contraction.
• B. Facilitates digestion in the stomach.
• C. Stimulates insulin release.
• D. Regulates digestion by maintaining normal pH.

Answer: (D)

Secretin is a hormone released by S cells of the duodenum in response to acidic chyme entering from the stomach. Its main role is to regulate digestion by maintaining the pH in the small intestine. It does this by signaling the pancreas and bile ducts to secrete bicarbonate-rich fluids, which neutralize the acidic chyme. This neutralization creates the proper chemical environment for digestive enzymes to function effectively. Actions like stimulating gallbladder contraction are driven by another hormone (cholecystokinin), not secretin, and secretin’s primary digestive impact is on pH rather than initiating stomach digestion or insulin release.

Secretin is a hormone released by S cells of the duodenum in response to acidic chyme entering from the stomach. Its main role is to regulate digestion by maintaining the pH in the small intestine. It does this by signaling the pancreas and bile ducts to secrete bicarbonate-rich fluids, which neutralize the acidic chyme. This neutralization creates the proper chemical environment for digestive enzymes to function effectively. Actions like stimulating gallbladder contraction are driven by another hormone (cholecystokinin), not secretin, and secretin’s primary digestive impact is on pH rather than initiating stomach digestion or insulin release.