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Rectum - Anatomy & Physiology (view source)
Revision as of 13:28, 16 July 2008
, 13:28, 16 July 2008→Function
==Function==
==Function==
'''Defeacation''
*After the mass movements of the large intestine, the rectum becomes filled with faeces.
*This stimulates pressue sensitive cells in the wall of the rectum and initiates the defeacation reflex.
*The reflex causes a forceful contraction of the rectum, and relaxation of the internal anal sphincter.
**This produces the conscious sensation of the need to empty the bowel.
**Some species (see species differences) are able to voluntarily keep the external anal sphincter closed if defeacation is not suitable for the situation.
***This reduces the defeaction reflex and reduces the conscious perception of needing to empty the bowel, until another mass movement occurs and a fresh reflex is created.
==Vasculature==
==Vasculature==