Rectum and anal canal (part 1)

The rectum is the distal portion of the large intestine. It is a continuation of the sigmoid colon, and is approximately 4.8 - 5.9 inches (12 - 15 cm) long and is rather fixed than mobile. The primary function of the rectum is a temporary storage of feces before they are further discharged from the large intestine through the anus during a process known as defecation. 

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