Learn the parts of digestion step-by-step with functions and a quiz
The digestive system is a group of organs that work together to break down food into nutrients your body can use for energy, growth, and repair. Digestion starts in the mouth where teeth chew food into smaller pieces and saliva begins breaking down starches. The tongue pushes food to the back of the throat where it enters the esophagus.
The esophagus is a muscular tube that moves food to the stomach using wave-like contractions called peristalsis. In the stomach, food is mixed with gastric juices containing hydrochloric acid and enzymes that break down proteins. Food stays in the stomach for two to four hours before moving to the small intestine.
The small intestine is where most digestion and nutrient absorption happens. It is about 20 feet long and lined with tiny finger-like projections called villi that increase surface area. The liver, gallbladder, and pancreas help by producing bile and digestive enzymes. After nutrients are absorbed, the remaining waste moves to the large intestine where water is absorbed before it exits the body.
This interactive tool lets students explore each organ of the digestive system, follow the path of food through the body, and take a quiz to test their knowledge. Great for life science in grades 3 through 6.
Last reviewed: April 2026