The gastrointestinal tract, often called the digestive system, is a long tube that runs from the mouth to the anus. It plays a crucial role in breaking down food, absorbing nutrients, and eliminating waste. The process begins in the mouth, where food is chewed and mixed with saliva, and continues through various organs like the stomach and intestines. As food travels through the gastrointestinal tract, it undergoes several transformations. In the stomach, it is mixed with digestive juices, while the small intestine absorbs most nutrients. Finally, any leftover waste moves into the large intestine before being expelled from the body.