• Describe the embryological formation of the components of the foregut, midgut and hindgut

Foregut gives rise to the following;

Oesophagus (which, in turn gives rise to Tracheo-bronchial tree) • Stomach • Proximal duodenum • Liver and gall bladder • Pancreas

Midgut gives rise to the following;

distal duodenum

jejunum

ileum caecum

ascending colon and proximal two thirds of the transverse colon

Hindgut gives rise to the following

Distal 1/3 transverse colon, descending and sigmoid colon, and the upper two thirds of the anorectal canal

The ‘Primitive gut tube’ which is within the endoderm gives rise to all parts of the GIT

the gut tube is shown below, the caudal end gives rise to the hind gut and the cranial end gives rise to the oropharyngeal membrane

the vitellin duct is formed from the midgut to the umbilicus to allow for nutrient supply from the yolk sac although by week 6-8 of development it should be obliterated and if it is not pathologies can occur