CAMRT Radiography Practice Exam

What sphincter regulates the passage of food into the duodenum?

1. Cardiac sphincter

2. Pyloric sphincter

3. Iliocecal sphincter

4. Anal sphincter

The correct answer is: Pyloric sphincter

The pyloric sphincter plays a crucial role in regulating the passage of food from the stomach into the duodenum, which is the first part of the small intestine. This sphincter is located at the lower end of the stomach and acts as a gatekeeper, controlling the release of chyme (the semi-liquid mixture of food) into the duodenum. By ensuring that the contents of the stomach are adequately processed and mixed with digestive enzymes and acids, the pyloric sphincter helps facilitate the beginning of nutrient absorption while also preventing backflow into the stomach. In contrast, the other options serve completely different functions in the digestive system. The cardiac sphincter, also known as the lower esophageal sphincter, is responsible for preventing the backflow of stomach contents into the esophagus. The iliocecal sphincter regulates the passage of material from the small intestine into the large intestine, while the anal sphincter controls the expulsion of feces from the rectum. Understanding the specific roles of these different sphincters is essential for grasping the overall process of digestion and the directed movement of food through the gastrointestinal tract.