Embryology of GU and GI Systems Flashcards
(30 cards)
What embryological layer forms the gut tube?
The endoderm
The _______________ suspends the entire length of the gut from the posterior abdominal wall.
The Dorsal Mesentery
Suspends the entire length of the gut from the posterior abdominal wall
What 2 structures arise from the ventral mesentery?
the falciform ligament and lesser omentum
Name the 7 Derivatives of the Foregut.
1st and 2nd parts of the duodenum Esophagus Liver (Hepatic diverticulum) Gall bladder (Hepatic diverticulum) Biliary apparatus (Hepatic diverticulum) Pancreas Stomach
Name the 6 Derivatives of the Midgut.
Ascending colon 2nd, 3rd, 4th parts of duodenum Jejunum Ileum Cecum with appendix Proximal 2/3 of Transverse colon
Name the 4 Derivatives of the Hindgut.
Distal 1/3 of Transverse colon
Descending colon
Sigmoid colon
Rectum
What is the Blood Supply of the Embryological Gut?
Foregut - Celiac trunk
Midgut - superior mesenteric artery (SMA)
Hindgut - inferior mesenteric artery (IMA)
Define recanalization in the embryological gut tube.
Opens holes in the embryological gut tube
Define stenosis in the embryological gut tube.
Partial recanalization of the gut tube due to an inability to generate a full hole
Define atresia in the embryological gut tube.
A failure to recanalize at all; no hole opening in the gut
Define Duodenal atresia.
Duodenal atresia – the inability to pass food from the gut tube through to the duodenum because there is no hole
What is the Adult Derivative of the LEFT Umbilical Vein?
The left umbilical vein forms the ligamentum teres/round ligament of liver.
The stomach rotates ________ or _________on its longitudinal axis
The stomach rotates 90 degrees to the right or clockwise on its longitudinal axis
Midgut rotation is a _________ of rotation of ______ degrees around the _____________as its longitudinal axis for rotation.
Midgut rotation is a Counter-clockwise of rotation of 270 degrees around the Superior Mesenteric Artery (SMA) as its longitudinal axis for rotation.
What causes Omphalocele?
It results from failure of return of the intestine to the abdominal cavity (covered by peritoneum)
What forms from the ventral and dorsal pancreatic buds?
The ventral pancreatic bud becomes most of the head of the pancreas, including the uncinate process
The dorsal pancreatic bud becomes the remainder of the pancreas
What forms the annular process of the pancreas?
The annular process is formed by fusion of ventral and dorsal buds all around the 2nd part of the duodenum
What are symptoms of an annular pancreas?
A baby will present with vomit that contains bile and complete/partial bowel obstruction
Hemorrhoids above the pectinate will be _________ because of ________ innervation.
Hemorrhoids above the pectinate will be painless because of GVA visceral innervation.
Hemorrhoids below the pectinate will be _________ because of ________ innervation.
Hemorrhoids below the pectinate will be painful because of GSA somatic innervation.
What is Congenital Megacolon (Hirschprung’s) and its cause.
A Congenital Abnormality: s a result of a failure to pass meconium in a full term baby.
Neural crest cells responsible for bowel peristalsis (autonomic innervation) fail to migrate, causing constipation, colonic dilation, and bowel obstruction (no autonomic innervation).
What is Meckel’s (ileal) Diverticulum?
A congenital Abnormality due to a remnant of the vitelline duct that causes a syndrome of 2’s:
2 feet from ileocolic IC valve 2 inches long 2% of population 2% symptomatic 2 types of ectopic tissue (gastric and pancreatic) 2 years of age at clinical presentation 2X more common in boys
The ______________ becomes the Median umbilical ligament .
The obliterated Urachus becomes the Median umbilical ligament .
The ____________ becomes the Medial umbilical folds.
The obliterated umbilical artery becomes the Medial umbilical folds.
