In this video, we look atge the histology of the ano-rectal junction which forms the pectinate line. Here, we will see how the mucosa and muscle layers transition abruptly as we go from the rectum to the anus. 0:00 introduction 0:36 transition of epithelium 1:26 internal anal sphincter 2:10 rectal mucosa 2:29 anal mucosa 2:34 pectinate line