The anus is part of the digestive system.
Function of the anus
The anus is the terminal opening of the digestive tract which follows on directly from the rectum. The anus controls defecation of faecal matter in the rectum.
Structure of the anus
The anus is composed of two sphincters (internal and external) which control defecation and provide continence. The Morgagni column, invaginations of the anal mucosa form the anorectal junction.
The anus follows the rectum, the last part of the digestive tract. © Medscape