Embryology Flashcards
When does the gut tube form?
During lateral and longitudinal folding
What are the 3 regions formed from the gut tube?
Foregut
Midgut
Hindgut
Where does the oropharyngeal membrane located?
Foregut
What region of the gut tube does the yolk sac remained connected to?
Midgut
Which region of the gut tube is the cloacal membrane?
Hindgut
What is the allantois?
Diverticulum from the hindgut that bulges into the connecting stalk
What is the gut tube surrounded by?
Visceral lateral plate mesoderm
What structures will the gut tube eventually form?
Epithelial lining of guts and organs
What does the visceral lateral plate mesoderm surrounding gut tube eventually form?
Smooth muscle
Connective tissue
Visceral peritoneum
True or False. Initially the gut tube is disconnected from the dorsal body wall.
False. It is connected by the dorsal mesentery
What is a mesentery?
Double layer of visceral peritoneum
True or False. Dorsal mesentery is just 2 layers of peritoneum.
False. It is, but there are vessels and nerves running between the layers as well.
Which regions of the gut does the dorsal mesentery remain in?
All 3: foregut, midgut, hindgut
What portion of the gut tube does the ventral mesentery form from?
Foregut
What structure forms the ventral mesentery?
Septum Transversum
What two structures form from the ventral mesentery?
Lesser omentum
Falciform ligament
Dorsal mesentery connects what to what?
Gut tube to dorsal wall
Intraperitoneal organs are:
Suspended in the abdominal cavity by a mesentery
True or False. Retroperitoneal organs are not covered by peritoneum.
False. They have peritoneum on their anterior surface only
What is the difference between a primarily and secondarily retroperitoneal organ?
Primarily- was never enclosed by a mesentery
Secondarily- was at one point enclosed by mesentery
True or False. The esophagus is entirely intraperitoneal.
False. The thoracic esophagus is retroperitoneal but the abdominal esophagus is intraperitoneal.
True or False. The entire colon is intraperitoneal.
False. The transverse and sigmoid colons are intraperitoneal but the ascending and descending colons are secondarily retroperitoneal.
What 4 structures are secondarily retroperitoneal?
Pancreas
Duodenum
Ascending colon
Descending colon
The aorta and IVC are intra or retroperitoneal?
Primarily retroperitoneal
The rectum is intra or retroperitoneal?
Subperitoneal
Which arteries supply the foregut?
Celiac Trunk
Which artery supplies the midgut?
Superior mesenteric artery
What artery supplies the hindgut?
Inferior mesenteric artery
What nerves innervate the foregut? Where do they originate and which ganglion are they associated with?
Greater splanchnic
T5-T9
Celiac ganglion
What nerves innervate the midgut? Where do they originate and which ganglion are they associated with?
Lesser and least splanchnic
T10-T12
Superior mesenteric ganglion
What nerves innervate the hindgut? Where do they originate and which ganglion are they associated with?
Lumbar splanchnics
L1-L2
Inferior mesenteric ganglion
Which parasympathetic nerve supplies the foregut?
Vagus
Which parasympathetic nerve supplies the midgut?
Vagus
Which parasympathetic nerve supplies the hindgut?
Pelvic splanchnics
S2-S4
Which gut tube forms pharynx?
Foregut