The backflow of faecal matter is prevented by

The opening between the ileum and caecum is guarded by ileo-caecal valve, which prevents the back flow of the faecal matter. The anal sphincter controls the release of the stool. There are two anal sphincters – external sphincter (voluntary) and internal sphincter (involuntary). The pyloric sphincter regulates the flow of chyme into the duodenum. Sphincter of Oddi controls the release of bile juice and pancreatic juice into the duodenum.