What is Rectum ? :
Rectum is the final straight portion of the large intestine in some mammals, and the gut in others. The human rectum is about 12 centimeters (4.7 in) long, and begins at the rectosigmoid junction, It terminates at the level of the anorectal ring (the level of the puborectalis sling) or the dentate line In humans, the rectums followed by the anal canal, before the gastrointestinal tract terminates at the anal verge.
As being the last part of the digestive tract, the rectum acts as a
temporary storage facility for feces / waste material. These feces remain in rectum until we proceed with defecation in which through bowel movement they are transferred to anal canal and then outside of the body