http://upload.wikimedia.org/wikipedia/commons/9/9a/Gray27.png

Note we define this generically to include invertebrates (partly for consistency with GO), but the class may be split in future. In vertebrates the term may refer to a developmental structure

The anterior portion of the primitive digestive tube of the embryo that lies cephalic to the junction of the yolk stalk, consists of endodermal tissue, and gives rise to the the pharynx, lower respiratory system, esophagus, stomach, duodenum proximal to the biliary tract, liver, pancreas, biliary tract, and gall bladder.

uberon

proenteron, praeenteron

The bilaterian gut is typically a complete tube that opens to the exterior at both ends. It consists of mouth, foregut, midgut, hindgut, and anus (reference 1); Although all vertebrates have a digestive tract and accessory glands, various parts of this system are not necessarily homologous, analogous, or even present in all species. Therefore, broad comparisons can be best made under the listings of headgut, foregut, midgut, pancreas and biliary system, hindgut (reference 2).[well established][VHOG]

UBERON:0001041

• midgut

• esophagus
• liver primordium
• pancreatic epithelial bud
• lung primordium
• cavity of pharynx
• upper digestive tract
• lung epithelium

• foregut epithelium
• gland of foregut
• foregut duodenum mesentery
• stomach
• pharyngeal region of foregut