Skip to content
My WebMD Sign In, Sign Up

Image Collection:

Human Anatomy

anus

Picture of the Anus

back buttonnext button

© 2012 WebMD, LLC. All rights reserved.

The anus is the opening where the gastrointestinal tract ends and exits the body. The anus starts at the bottom of the rectum, the last portion of the colon (large intestine). The anorectal line separates the anus from the rectum.

Tough tissue called fascia surrounds the anus and attaches it to nearby structures.

Circular muscles called the external sphincter ani form the wall of the anus and hold it closed. Glands release fluid into the anus to keep its surface moist.

A plate-like band of muscles, called the levator ani muscles, surround the anus and form the floor of the pelvis. A network of veins lines the skin of the anus.

Today on WebMD

man holding his stomach
Get the facts on common problems.
blueberries in a palm
Best and worst foods.
 
woman shopping
Learn what foods to avoid.
fresh and dried plums
Will it help constipation?
 
top foods for probiotics
Slideshow
couple eating at cafe
Article
 
sick child
Slideshow
Woman blowing bubble gum
Slideshow
 

Send yourself a link to download the app.

Loading ...

Please wait...

This feature is temporarily unavailable. Please try again later.

Thanks!

Now check your email account on your mobile phone to download your new app.

Woman with crohns in pain
Slideshow
Woman with stomach pain
Slideshow
 
diet for diverticulitis
Video
what causes diarrhea
Video