duodenum

The first part of the small intestine. At the junction of the stomach and the duodenum the alimentary canal is inflected. The duodenum first goes anteriorly for a short distance, turns dorsally, and eventually caudally, thus it is a U-shaped structure with two horizontal sections (a ventral and a dorsal one). Every claim on this page comes from the Leumas anatomy graph and carries its source.

What the duodenum is

The first part of the small intestine. At the junction of the stomach and the duodenum the alimentary canal is inflected. The duodenum first goes anteriorly for a short distance, turns dorsally, and eventually caudally, thus it is a U-shaped structure with two horizontal sections (a ventral and a dorsal one). The atlas records it as a organ at the organ scale in the human body.

Where the duodenum is

It sits within the digestive system. Positioned deliberately as part of this species body plan.

What the duodenum connects to

The atlas records 27 typed relationships for it, across 10 kinds of connection. part of small intestine.

Supply and innervation

Arterial supply: retroduodenal artery and supraduodenal artery.

Also called

Also recorded as proximal intestine and upper intestine. Searching any of those names reaches this page.

Source

Uberon multi-species anatomy ontology (Mungall et al.), CC BY 4.0. Term UBERON:0002114, version 2026-06-19, retrieved 2026-08-24. Licence: CC-BY-4.0.

• Part of: small intestine.
• A kind of: subdivision of digestive tract.
• Attaches to: suspensory ligament of duodenum.
• Adjacent to: pyloric sphincter.
• contains: crypt of Lieberkuhn of duodenum, duodenal ampulla, duodenal epithelium, duodenal gland, duodenal mucosa and duodenum lamina propria, and 6 more.
• flows to: jejunum, stomach, gallbladder and pancreas.
• connects: duodeno-jejunal junction, gastroduodenal junction and hepatoduodenal ligament.
• Supplied by: retroduodenal artery and supraduodenal artery.

Questions

Where is the duodenum?

It sits within the digestive system. Positioned deliberately as part of this species body plan.

What does the duodenum connect to?

Part of: small intestine.

Is the duodenum the same in other species?

Leumas holds the same relationship vocabulary for every species it carries, so where another dataset records this structure you can put the two side by side on /compare.