What does the rectum primarily collect from the digestive process?

The rectum primarily functions as the final section of the large intestine, responsible for storing undigested waste material until it is expelled from the body during the act of defecation. As food passes through the digestive system, nutrients and most of the water are absorbed in earlier sections, such as the small intestine and the colon. By the time material reaches the rectum, it consists mainly of undigested food remnants, fiber, and other waste products that are no longer needed by the body. This collection prepares the waste for eventual elimination, making it clear that the rectum's primary role is in the storage of this undigested waste before it is expelled.