The digestive system is a tube-like system that begins with the mouth and includes the esophagus, stomach, liver, pancreas, gallbladder, and rectum. Food enters the mouth and is broken down through chewing and the actions of these organs. The esophagus transports food to the stomach using muscle movements, while the stomach churns and bathes food in acid. The liver, pancreas, and gallbladder produce enzymes and bile to further break down food, and the rectum stores waste before it exits the body.