Question

Once the undigested and unabsorbed substances enter the caecum, their backflow is prevented by

• A. Ileo-caecal valve
• B. Gastro-oesophageal sphincter
• C. Pyloric sphincter
• D. Sphincter of Oddi

Answer 1

The Correct Option is A

The question pertains to the physiological mechanism that prevents the backflow of substances from the caecum into the ileum of the small intestine. The correct answer to this particular query is the "Ileo-caecal valve." Let's understand why:

The ileo-caecal valve is a crucial anatomical structure located between the ileum of the small intestine and the caecum of the large intestine. Its primary function is to act as a barrier that controls the flow of materials, ensuring that digested and absorbed nutrients proceed in the right direction through the digestive tract while preventing any reverse movement, or backflow, of materials from the caecum back into the ileum.

In contrast, the other options serve different purposes in the digestive system:

• Gastro-oesophageal sphincter: This is responsible for preventing acid reflux from the stomach back into the esophagus.
• Pyloric sphincter: This regulates the passage of digested food from the stomach into the duodenum (the first part of the small intestine).
• Sphincter of Oddi: It controls the flow of bile and pancreatic juice from the bile duct and pancreatic duct into the duodenum.

Only the ileo-caecal valve performs the specific function of preventing backflow of intestinal contents from the caecum into the ileum, ensuring one-way passage along the digestive tract.