Anal canal

From Wikipedia, the free encyclopedia

Jump to: navigation, search
 This article does not cite any references or sources. (December 2007)
Please help improve this article by adding citations to reliable sources. Unverifiable material may be challenged and removed.
Anal canal
Coronal section of rectum and anal canal.
Coronal section through the anal canal. B. Cavity of urinary bladder V.D. Ductus deferens. S.V. Seminal vesicle. R. Second part of rectum. A.C. Anal canal. L.A. Levator ani. I.S. Sphincter ani internus. E.S. Sphinear ani externus.
Latin canalis analis
Gray's subject #249 1184
Artery inferior rectal artery
Vein inferior rectal vein
Lymph superficial inguinal lymph node (below pectinate line) internal iliac lymph nodes (above line)
Precursor hindgut, proctodeum
MeSH Anal+Canal
Dorlands/Elsevier c_04/12208538

The anal canal is the terminal part of the large intestine.

It is situated between the rectum and anus, below the level of the pelvic diaphragm. It lies in the anal triangle of perineum in between the right and left ischiorectal fossae.

In humans it is approximately 2.5 to 4 cm long, extending from the anorectal junction to the anus. It is directed downwards and backwards. It is surrounded by inner involuntary and outer voluntary sphincters which keep the lumen closed in the form of an anteroposterior slit.

It is differentiated from the rectum by the transition of the internal surface from endodermal to skinlike ectodermal tissue.

Anatomy of the anus and rectum

Left Levator ani from within.

The interior of the anal cami and lower part of the rectum.

Median sagittal section of male pelvis.

Median sagittal section of female pelvis.

 This digestive system article is a stub. You can help Wikipedia by expanding it.
v • d • e
Anatomy of torso, digestive system: Gastrointestinal tract
Upper GI: to stomach Mouth • Pharynx (nasopharynx, oropharynx, hypopharynx) • Esophagus • Crop
Upper GI: stomach rugae - gastric pits - cardia/gland - fundus/gland - pylorus/gland - pyloric antrum - pyloric canal - greater curvature - lesser curvature - angular incisure
Lower GI: intestines Small intestine: Duodenum (Suspensory muscle, Major duodenal papilla, Minor duodenal papilla) • Duodenojejunal flexure • Jejunum • Ileum • continuous (intestinal villus, crypts of Lieberkühn, circular folds)

Junction: Vermiform appendix • Ileocecal valve

Large intestine: Cecum • Colon (ascending colon, hepatic flexure, transverse colon, splenic flexure, descending colon, sigmoid colon) • continuous (taenia coli, haustra, epiploic appendix)
Lower GI: termination Rectum: Houston valve • rectal ampulla • pectinate line

Anal canal: anal valves • anal sinuses • anal columns • Hilton's white line

Anus: Sphincter ani internus muscle • Sphincter ani externus muscle
Lower GI: lymph GALT: Peyer's patches (M cells)
Retrieved from "http://en.wikipedia.org/wiki/Anal_canal"
Advanced Search
Included Web Search Engines


Safe Search

close

Top Matching Results

Occasionally Search.com will highlight specialized results that are based on the context of your query. Examples of specialized results include specific links to news, images, or video.

Top Matching Results may highlight information from other Search.com pages, content from the CNET Network of sites, or third party content. The listings are based purely on relevance. Search.com does not receive payment for listings in this section but our partners that provide this data may get paid for listing these products.

Sponsored Links

This section contains paid listings which have been purchased by companies that want to have their sites appear for specific search terms and related content. These listings are administered, sorted and maintained by a third party and are not endorsed by Search.com.

Search Results

Search.com sends your search query to several search engines at one time and integrates the results into one list which has been sorted by relevance using Search.com's proprietary algorithm. You can customize the list of search engines included in your metasearch from the preferences.

The search engines that are used in your metasearch may allow companies to pay to have their Web sites included within the results. To view the Paid Inclusion policy for a specific search engine, please visit their Web site. Search.com does not accept payment or share revenue with any search engine partner for listings in this section.