The lower esophageal tone prevents what?

The lower esophageal tone prevents what?

• A. Gastroesophageal reflux
• B. Esophageal spasms
• C. Gastric ulcers
• D. Peptic ulcers

Answer: (A)

The barrier at the gastroesophageal junction is maintained by the lower esophageal sphincter, which keeps stomach contents from flowing back into the esophagus. Its resting tone acts like a valve to prevent gastroesophageal reflux, especially after meals or when intraabdominal pressure rises. Swallowing and belching involve brief LES relaxation to let the bolus pass, but overall the tone is what prevents reflux. The other options are not controlled by LES tone: esophageal spasms are a motility issue of the esophagus, and gastric or peptic ulcers are mucosal injuries in the stomach, not reflux-related failures of the valve.

The barrier at the gastroesophageal junction is maintained by the lower esophageal sphincter, which keeps stomach contents from flowing back into the esophagus. Its resting tone acts like a valve to prevent gastroesophageal reflux, especially after meals or when intraabdominal pressure rises. Swallowing and belching involve brief LES relaxation to let the bolus pass, but overall the tone is what prevents reflux. The other options are not controlled by LES tone: esophageal spasms are a motility issue of the esophagus, and gastric or peptic ulcers are mucosal injuries in the stomach, not reflux-related failures of the valve.