Embryology Flashcards
Which way does the stomach rotate?
It rotates clockwise so that the left vagal nerves end up anterior. Then it bends towards the duodenum (rotates along the anteroposterior axis)
What is the lesser peritoneal sac, and its borders?
The space created behind the stomach as the stomach rotates pulling the dorsal mesentery.
What do the dorsal and ventral mesenteries become
What are the derivatives of the foregut?
- Primordial pharynx
- Lower respiratory tract
- Esophagus
- Stomach
- Duodenum, proximal to major duodenal papilla
- Liver, biliary tree
- pancreas
How is the liver formed? What is the relation to the gallbladder and the pancreas?
Same idea as the duodenum, occlusion of the lumen by proliferating epithelial cells, then recanalization.
Liver bud grows off of foregut, right about where the duodenum is. The cranial part grows up to meet the septum transversum and the caudal part grows down to become the gall bladder. The stalk of the bud becomes the cystic duct
How is the pancreas formed?
There are two buds: a ventral bud (that comes off the stalk of the liver bud) and a dorsal bud (that comes off the opposite site of the foregut tube, at the level of the duodenum)
The duodenum rotates to make it’s “C” and the two buds come together and fuse. The accesory pancreatic duct comes from dorsal pancreatic bud and the main pancreatic duct comes from the ventral pancreatic duct.
What is the spleen formed from?
A mass of mesenchymal cells located between the layers of the dorsal mesogastrium
