Which process moves food through the digestive tract after ingestion?

• A. Circulation
• B. Peristalsis
• C. Respiration
• D. Perfusion

Answer: (B)

Movement of food through the digestive tract after ingestion is produced by peristalsis, coordinated, wave-like contractions of the smooth muscle in the walls of the alimentary canal. These propulsive waves push the food forward from the esophagus through the stomach and into the intestines, while mixing it with digestive secretions and aiding absorption. Peristalsis relies on the interaction of circular and longitudinal muscle layers and the enteric nervous system to ensure unidirectional flow. Circulation moves blood, respiration handles gas exchange in the lungs, and perfusion refers to blood flow through tissues—none of these move ingested material through the GI tract.