Embryology of GI Flashcards
Define Gastrulation
Occurs when a blastula (single layer) folds and enlarges to create a gastrula (three layers)
What are the three germ layers of a gastrula
ectoderm, mesoderm, endoderm
When does the primordial gut form
4th week
What is the cranial end closed by
oropharyngeal membrane
What is the caudal end closed by
cloacal membrane
What thee parts does the primordial gut tube divide into
foregut, midgut, hindgut
Endoderm of the primordial gut forms
most of gut, epithelium and glands
Epithelium from cranial and caudal end are derived from
ectoderm (stomodeum) and anal pit (proctodeum)
In 4th week the intra-embryonic coelom becomes
embryonic body cavity
Embryonic body cavity divides into
Pleural, Pericardial and Peritoneal cavities
Primordial pharynx derived from
foregut
Lower respiratory tract derived from
foregut
Oesophagus derived from
foregut
Stomach derived from
foregut
Duodenum (part above opening of bile and pancreatic duct) derived from
foregut
Liver derived from
foregut
Biliary apparatus derived from
foregut
Pancreas derived from
foregut
Oesophageal Atresia
congenital condition causing oesophagus to end in a blind end pouch. Caused by failure of recanalization
Tracheoesophageal fistula
abnormal connection in one or more places between the oesophagus and the trachea. Caused by abnormal deviation of trachea-oesophageal septum