Acidic chyme splashes into the esophagus, causing a burning pain commonly called heartburn or acid indigestion. This happens when ____.

A) excess gastrin is present in the blood
B) a sphincter does not close properly
C) the stomach is full
D) the chyme is too acidic
E) cells lining the esophagus release acid

Acidic Chyme

The partially digested, acidic food mixture that moves from the stomach to the small intestine.

Heartburn

A discomforting burning sensation in the chest, usually occurring after eating, caused by stomach acid refluxing back into the esophagus.

Sphincter

Ring of muscle in a tubular organ or at a body opening.