Which hormone regulates digestion by maintaining normal pH?

Which hormone regulates digestion by maintaining normal pH?

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

Answer: (D)

Maintaining the right pH in the digestive tract is achieved by secretin. When acidic chyme first enters the duodenum, S cells release secretin. This hormone signals the pancreas to secrete bicarbonate-rich juice (and also influences bile duct secretions), neutralizing the acid as it mixes with the chyme. That neutralization raises the pH to a level where digestive enzymes in the small intestine can function properly. Secretin also helps temper further acid release from the stomach, keeping digestion balanced as chyme moves along. The other options relate to different digestive roles—one describes gallbladder contraction, another promotes stomach digestion via acid secretion, and another controls insulin release—so they don’t regulate digestion by maintaining pH in the way secretin does.

Maintaining the right pH in the digestive tract is achieved by secretin. When acidic chyme first enters the duodenum, S cells release secretin. This hormone signals the pancreas to secrete bicarbonate-rich juice (and also influences bile duct secretions), neutralizing the acid as it mixes with the chyme. That neutralization raises the pH to a level where digestive enzymes in the small intestine can function properly. Secretin also helps temper further acid release from the stomach, keeping digestion balanced as chyme moves along. The other options relate to different digestive roles—one describes gallbladder contraction, another promotes stomach digestion via acid secretion, and another controls insulin release—so they don’t regulate digestion by maintaining pH in the way secretin does.