What is the omental bursa?
The space between the stomach and the posterior body wall.
What is the origin, blood supply, nerve supply, and lymphatic drainage for the inferior one third of the anal canal?
Origin: ectoderm (proctodeum).
Blood supply: middle and inferior rectals.
Nerve supply: pudendal nerve.
Lymphatic drainage: superficial inguinal lymph nodes.
The spleen is a part of the foregut — so it's endoderm derived, right?
NO, YOU IDIOT.
What gives rise to the falciform ligament of the liver?
The ventral mesentery.
How might esophageal atresia be diagnosed?
Insertion of an NG tube. If it coils after so many centimeters, esophageal atresia is confirmed.
When do the tracheoesophageal folds form, or if forming incorrectly, create a esophageal atresia / tracheoesophageal fistulae?
Why does the midgut have to leave the abdominal cavity and enter the umbilical cord?
Because it is growing faster than the abdominal cavity, because the liver is very large at this point (because it is performing hematopoiesis), and because the kidneys are taking up the length of the abdominal cavity as they are growing.
What would be the primary clinical difference between a symptomatic patient with an annular pancreas, and a symptomatic patient with pyloric stenosis?
In the case of the patient with pyloric stenosis, the vomit will be non-bilious because it hasn't reached the major duodenal papilla.
In the case of the annular pancreas, the vomit can be bilious because it may have.
What are the 3 parts of the dorsal mesogastrium?
What does each part go-between?
The splenorenal ligament goes between the spleen and the posterior body wall, passing by the kidney.
The gastrosplenic ligament goes between the stomach and the spleen.
The greater omentum, which does its own thing.
In the G.I. system, what comes from mesoderm – and what layer of mesoderm are we talking about?
The mesoderm of the G.I. is splanchnic mesoderm, which gives rise to smooth muscle and connective tissue.
Where does the striated muscle of the esophagus come from?
Mesoderm of the fourth and sixth pharyngeal arches.
What all hindgut membranes are made of endoderm and ectoderm?
The urogenital membrane.
The anal membrane.
The cloacal membrane
During which week does the midgut enter the umbilical cord, and during which week does it return from the umbilical cord?
The midgut leaves at week 6, and returns at week 10.
What disintegrates leaving the transverse pericardial sinus?
The dorsal mesocardium.
What are the main characteristics of a congenital diaphragmatic hernia?
What is the cause?
Characteristics: Displacement of the heart – typically to the right side. Displacement of intestinal contents into the thorax. Lung hypoplasia. Polyhydramnios.
Failure of the pleuroperitoneal membranes to close, resulting in a foramen of Bochdalek.
What is the adult structure of the septum transversum called?
The central tendon of the diaphragm.
What causes Meckel's diverticulum?
The vitelline duct pulling on the ileum creating a diverticulum.
What important G.I. structures come from the neural crest cells?
The autonomic ganglia of the plexus of Meissner and the plexus of Auerbach.
What are the intraperitoneal structures?
First 1/4 of the duodenum.
Tail of pancreas.
Jejunum and Ileum.
What are the urogenital membrane and the anal membrane made out of embryo logically?
Ectoderm and endoderm
What is the foramen of Bochdalek?
A large hole (typically on the left side) which forms as a result of the failure of the pleuroperitoneal membranes to close.
What structures arise from the midgut?
Distal duodenum (after the major duodenal papilla).
The rest of the small intestine.
The vermiform (cecum) appendix.
The ascending colon.
The proximal (right) half of the transverse colon.
What is the function of the dorsal mesogastrium?
Gives rise to the greater omentum.
What embryological layer does that the pleuroperitoneal membrane come from?
Somatic layer of the lateral plate mesoderm.
What structure grows ventrally out from the foregut just below the stomach?
The hepatic diverticulum.
What structures come from the foregut?
The pharynx (and derivatives).
The respiratory system (!).
The liver and pancreas.
The biliary apparatus.
The proximal duodenum (up to the major duodenal papilla).
What is the total rotation of the midgut?
90° in the umbilical cord, 180° when it returns.
A total of 270° rotation.
What structures form from the urogenital membrane?
The bladder and urethra.
When does bile start being produced?
The 12th week
What structures arise from the hindgut?
Distal (left) half of the transverse colon.
The superior anal canal.
The epithelium of the urinary bladder and urethra.