Buccopharyngeal membrane is future ____. Cloacal membrane is future _____.
Mouth
Butthole
Which embryological structure connect gut tube to the yolk sac?
vitelline duct
Embryological layer for: gut tube, liver and pancreas, peritoneal, neuro crest GI tract
Gut tube- endoderm
Liver and pancreas- endoderm
Peritoneal- endoderm
Neuro crest- ectoderm
Which embryological structure is often considered to be part of the foregut?
Pharyngeal gut
True/false: spleen is derived from the foregut tube
False; spleen isn’t however spleen is considered in the foregut because of blood supply (celiac trunk)
Ventral stomach receives innervation from _____ vagal trunk; dorsal stomach receives innervation from _____ vagal trunk.
Anterior (was the left vagus up in the neck)
Posterior (was the right vagus; think LARP)
Which direction does the stomach rotate?
clockwise, 90 degrees along the longitudinal
Which side of the stomach enlarges?
Posterior side, forming the greater curvature of the stomach
Pancreas is formed from two endodermal buds, where does the ventral bud move?
Dorsally, ultimately fusing with dorsal bud
What does the ventral bud of pancreas give rise to? Dorsal bud?
Ventral bud: uncinate process, inferior head, main pancreatic duct
Dorsal bud: accessory pancreatic duct, proximal main pancreatic duct
Accessory pancreatic duct is form from which endodermal bud?
Dorsal bud
When does rapid liver development occur?
Rapid growth in weeks 5 through 10
True/false: liver, gallbladder, and bile duct system arise together as ventral outgrowth from the foregut
True
How does oxygenated blood get to the fetus?
Travel from the placenta through the umbilical vein towards the fetus
What is the developmental blood bypassing the liver called?
Ductus venosus
What is the ductus venosus?
Connects the umbilical vein to the inferior vena cava allowing most oxygenated blood to bypass the liver and get to the heart
Liver develop between layers of ____mesentery; spleen develops in ___ mesentery
Ventral
Dorsal
True/false: spleen, along with the pancreas, liver, gallbladder and bile duct, is also formed from an outgrowth of the foregut tube
False; spleen is not an outgrowth form the foregut tube. Spleen is developed from a mass of mesenchymal cells.
Primary intestinal loop rotates around axis formed by the ______
Superior mesentery artery
Primary intestinal loop’s rotation is ______ and total of_____ degrees
Counterclockwise
270
When does the intestinal loop exit the body? When does it come back to the abdominal cavity?
Week 6
Week 10
Gut herniates into the umbilical cord at week 6, bowel rotates ____ degrees ______ rotation. When it returns to abdominal cavity at week 10, it undergoes and additional _____180 degrees ____ rotation
90, CCW
180, CCW
What is an omphalocele?
Malformation of the intestines where the intestines do not return to the abdominal cavity and remain inside the umbilical cord for the remainder of development
Omphalocele ___(is/Is not) contained in a sac that consists of peritoneum and other membranes. Whereas gastroschisis ____(is /is not ) contained in a sac.
Is
Is not
Vitelline duct eventually becomes what structure?
umbilical cord
What is a meckel’s diverticulum?
aka an illeal diverticulum; where a small segment of the vitelline duct persists
50 cm proximal to the ileocecal valve
What results if the vitelline duct remains patent for its entire length?
Umbilical fistula or vitelline fistula
Poop from the umbilicus
What could result from an abnormal partitioning of the cloaca?
anorectal agenesis – no butthole
What is the embryological layer of upper anal canal? Lower anal canal?
Upper: Endoderm (part of hindgut)
Lower: ectoderm
What is the blood supply to the lower anal canal? Upper anal canal?
Lower: Inferior rectal arteries
Upper: superior rectal artery, branch of IMA
What are mesenteries?
Double layers of peritoneum that suspend the gut
True/false: entire gut tube has a ventral mesentery
False; entire gut tube has DORSAL mesentery, but only foregut has ventral mesentery
