The anus is that part of the intestinal tract that passes through the muscular canal of the pelvis and anal sphincters. It is the final orifice through which stool passes out of the body. In adults, the anus is 4 to 5 centimeters long. The lower half of the anal canal has sensitive nerve endings. There are blood vessels under the lining, and in its mid portion there are numerous tiny, anal glands. This article describes four disorders that cause anal pain and irritation:. Anal fissure - An anal fissure, also called an anorectal fissure, is a linear split or tear in the lining "anoderm" of the lower anal canal.

The anal glands also referred to as the anal sacs are two sebaceous glands located on either side of the anus that secrete a pungent fluid. They are found in many mammals, including cats, dogs, and bears. But what about humans? Do humans have anal glands?

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