The digestive system is made up of the digestive tract and other organs that help break down food. The digestive tract runs from the mouth to the anus and includes the esophagus, stomach, small intestine, and large intestine. Digestion involves mixing food with digestive juices and moving it through the tract, breaking down molecules. The mouth, stomach, and small intestine play key roles in breaking down food, while the liver, pancreas and other organs produce juices to aid digestion and absorb nutrients. The large intestine finishes digestion before waste is excreted.