Which structure regulates the flow of contents from the stomach to the duodenum?

• A. Cardiac sphincter
• B. Lower esophageal sphincter
• C. Pyloric sphincter
• D. Ileocecal valve

Answer: (C)

Verified step by step guidance

1. Step 1: Understand the anatomy of the stomach and its connection to the duodenum. The stomach is a muscular organ that connects to the duodenum, the first part of the small intestine, via a structure that regulates the flow of partially digested food (chyme).
2. Step 2: Identify the role of sphincters in the digestive system. Sphincters are circular muscles that act as valves to control the passage of substances between different parts of the digestive tract.
3. Step 3: Differentiate between the listed structures. The cardiac sphincter (also known as the lower esophageal sphincter) regulates the flow of food from the esophagus into the stomach. The ileocecal valve regulates the flow of contents from the small intestine to the large intestine. The pyloric sphincter specifically controls the flow of chyme from the stomach to the duodenum.
4. Step 4: Focus on the pyloric sphincter. The pyloric sphincter is located at the distal end of the stomach and acts as a gatekeeper, ensuring that chyme is released into the duodenum in controlled amounts to facilitate digestion and absorption.
5. Step 5: Confirm the correct answer. Based on the anatomical function, the structure that regulates the flow of contents from the stomach to the duodenum is the pyloric sphincter.