Which structure marks the gateway between the esophagus and the stomach?

• A. Cardia
• B. Pyloric sphincter
• C. Fundus
• D. Lower esophageal sphincter

Answer: (D)

The gateway between the esophagus and the stomach is the lower esophageal sphincter, a ring of smooth muscle at the gastroesophageal junction. Its main job is to allow a swallowed bolus to pass into the stomach while keeping gastric contents from refluxing back into the esophagus. The term cardia refers to the region of the stomach around this opening, not the gateway itself. The pyloric sphincter sits at the other end of the stomach, controlling passage into the small intestine, and the fundus is the upper, dome-shaped part of the stomach.