Anus

The anus is a muscular organ at the end of the gastro-intestinal tract.^[1] It is a sphincter, and can be controlled to open for expulsion of gas or feces.

References

↑ Phil Owen (2019-03-01). "Upper vs. Lower GI Tract: What Are They?". Austin Gastroenterology. Archived from the original on 2026-05-20. Retrieved 2026-08-03. The path food takes in the body, in the gastrointestinal (GI) tract, starts with the mouth and ends with the anus (rectum). The GI tract is divided into two main sections: the upper GI tract and the lower GI tract. The upper GI tract is generally considered to be the mouth, esophagus, stomach, and finally the first part of the small intestine (duodenum). The lower GI tract runs from the small intestine to the large intestine (colon) to the anus.

[AustinGastroenterology-2019-03-01-1] Phil Owen (2019-03-01). "Upper vs. Lower GI Tract: What Are They?". Austin Gastroenterology. Archived from the original on 2026-05-20. Retrieved 2026-08-03. The path food takes in the body, in the gastrointestinal (GI) tract, starts with the mouth and ends with the anus (rectum). The GI tract is divided into two main sections: the upper GI tract and the lower GI tract. The upper GI tract is generally considered to be the mouth, esophagus, stomach, and finally the first part of the small intestine (duodenum). The lower GI tract runs from the small intestine to the large intestine (colon) to the anus.

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