Rectum

Rectum
Scheme of digestive tract, with rectum marked
Anatomy of the anus and rectum
Details
Precursor	Hindgut
Part of	Large intestine
System	Gastrointestinal system
Artery	Superior rectal artery (first two-thirds of rectum), middle rectal artery (last third of rectum)
Vein	Superior rectal veins, middle rectal veins
Nerve	Inferior anal nerves, inferior mesenteric ganglia[1]
Lymph	Inferior mesenteric lymph nodes, pararectal lymph nodes, internal iliac lymph nodes, deep inguinal lymph nodes
Function	Store feces prior to defecation
Identifiers
Latin	rectum intestinum
MeSH	D012007
TA98	A05.7.04.001
TA2	2998
FMA	14544
Anatomical terminology [edit on Wikidata]

Major parts of the
Gastrointestinal tract
Upper gastrointestinal tract Mouth Pharynx Esophagus Stomach Duodenum
Lower gastrointestinal tract Small intestine Jejunum Ileum Large intestine Cecum Appendix Ascending colon Transverse colon Descending colon Sigmoid colon Rectum Anus
See also Gastrointestinal wall Human digestive system Anatomical terminology Outline of anatomy
v t e

The rectum (pl.: rectums or recta) is the final straight portion of the large intestine in humans and some other mammals, and the gut in others. The adult human rectum is about 12 centimetres (4.7 in) long,^[2] and begins at the rectosigmoid junction (the end of the sigmoid colon) at the level of the third sacral vertebra or the sacral promontory depending upon what definition is used.^[3] Its diameter is similar to that of the sigmoid colon at its commencement, but it is dilated near its termination, forming the rectal ampulla.^[4] It terminates at the level of the anorectal ring (the level of the puborectalis sling) or the dentate line, again depending upon which definition is used.^[3] In humans, the rectum is followed by the anal canal, which is about 4 centimetres (1.6 in) long, before the gastrointestinal tract terminates at the anal verge. The word rectum comes from the Latin rēctum intestīnum, meaning straight intestine.