1,362
edits
Changes
→Histology
==Histology==
==Histology==
[[Image:Anal Sacs.jpg|thumb|right|150px|Anal Sacs- Copywright RVC 2008]]
*At the anus, the columnar intestinal epithelium is replaced by the stratified squamous keratinised epithelium of the skin.
*At the anus, the columnar intestinal epithelium is replaced by the stratified squamous keratinised epithelium of the skin.
*As the muscosa changes from columnar to cutaneous, three zones are created:
*As the muscosa changes from columnar to cutaneous, three zones are created:
***Stratified squamous keratinised epithelium.
***Stratified squamous keratinised epithelium.
***Surrounds the anus.
***Surrounds the anus.
***Excretory ducts of the anal sacs open into this region.
***Excretory ducts of the '''anal sacs''' open into this region.
****Large, coiled apocrine tubules.
****Large, coiled apocrine tubules.
****Have many glands in their walls.
****Have many glands in their walls.