Which two circular rings of muscle act as gatekeepers for the stomach?

• A. Ileocecal valve and cardiac sphincter
• B. Lower esophageal sphincter and pyloric sphincter
• C. Tricuspid valve and mitral valve
• D. Anal sphincter and upper esophageal sphincter

Answer: (B)

Verified step by step guidance

1. Step 1: Understand the anatomy of the stomach and its connection to surrounding structures. The stomach is part of the digestive system and has muscular rings (sphincters) that regulate the flow of food and prevent backflow.
2. Step 2: Identify the two key sphincters associated with the stomach. The lower esophageal sphincter (also called the cardiac sphincter) is located at the junction between the esophagus and the stomach, preventing acid reflux. The pyloric sphincter is located at the junction between the stomach and the small intestine, controlling the passage of partially digested food into the duodenum.
3. Step 3: Compare the options provided in the question. The ileocecal valve is located between the small intestine and large intestine, and the tricuspid and mitral valves are part of the heart, not the digestive system. The anal sphincter and upper esophageal sphincter are not directly related to the stomach's function.
4. Step 4: Eliminate incorrect options based on anatomical relevance. The correct answer must involve sphincters directly connected to the stomach, which are the lower esophageal sphincter and pyloric sphincter.
5. Step 5: Confirm the correct answer by reviewing the function of the lower esophageal sphincter (preventing acid reflux) and the pyloric sphincter (regulating food passage into the small intestine). These two sphincters act as gatekeepers for the stomach.