Final answer:
The process by which undigested material is removed from the gastrointestinal tract is elimination. It occurs in the colon and rectum, and involves peristaltic movements to move the waste and eliminate it through the anus.
Step-by-step explanation:
The process by which undigested material is removed from the gastrointestinal tract is elimination. It is the final step in digestion and occurs in the colon and rectum. Undigested food matter enters the colon, where most of the water is reabsorbed. The waste is moved through the colon by peristaltic movements and is stored in the rectum until elimination through the anus.