Chapter 14: The Digestive System

Children are fascinated with the workings of the digestive system: They relish crunching a potato chip, delight in making "mustaches" with milk, and giggle when their stomach "growls." As adults, we know that a healthy digestive system is essential for good health, because it converts food into the raw materials that build and fuel our body's cells. Specifically, the digestive system takes in food (ingests it), breaks it down physically and chemically into nutrient molecules (digests it), and absorbs the nutrients into the bloodstream. Then it rids the body of the indigestible remains (defecates).