Anatomy And Physiology CFE Practice Exam

Mechanical digestion is the physical breakdown of food into smaller pieces to increase surface area for enzymes. This starts in the mouth, where teeth chew and mix food with saliva. In the stomach, muscular contractions churn and mix the contents, further breaking them into a semi-liquid form. In the small intestine, rhythmic segmentation helps mix and move the contents, aiding further breakdown and preparation for chemical digestion and absorption. So the set that includes mouth, stomach, and small intestine matches all the sites where these mechanical processes actively occur. The other options pair organs that aren’t primarily involved in mechanical breakdown—esophagus mainly moves everything along, the large intestine focuses on water absorption, and liver/pancreas/gallbladder are mainly secretory, not mechanical, functions.