Development of Digestive System Flashcards
lateral plates fold and meet at midline into the embryo forming the
primitive gut tube
cranial fold will incorporate the part of the endoderm (primitive gut tube) forming the
foregut
remains in contact with the yolk stalk because it is not completely enclosed by the lateral plates of mesoderm
midgut region
caudal fold incorporates endodermal tissue which will become
hindgut region of the primitive gut tube
the ____ of the primitive gut tube develops into the epithelial lining and glands of the digestive system
endoderm
the ____ develops into smooth muscle, connective tissue, and outer layers of abdomen organs
splanchnic mesoderm
depressed area of surface ectoderm that develops near the anteriormost endoderm of the foregut
stomodeum
depression in ectoderm that forms near the caudal end of the hindgut
proctodeum (lower anus)
elongates and develops into the pharynx, esophagus, thyroid, stomach, and the proximal portion of the duodenum
foregut
all foregut organs, except pharynx, respiratory epithelium and esophagus, are vascularized by branches of
celiac artery
at what week does the stomach in for foregut rotate 90* clockwise @ the long axis
week 4
the enlarged dorsal border of the stomach will become
the greater curvature of the stomach
during the stomach rotation, ventral border rotates ___ and dorsal border rotates ____
ventral -> right
dorsal -> left
as the stomach rotates, it pulls the dorsal mesentery to the LEFT forming the
omental bursa (lesser sac)
large recess in the peritoneal cavity
omental bursa
liver and bilary duct system arise from the ____ within the ventral mesentery
foregut
in week 4 of the liver production, a ______ forms which is connected to the _______
hepatic diverticulum, septum transversum
what are the two parts the hepatic diverticulum divide into
- cranial portion
2. smaller caudal portion
all ligaments that attach to the liver are derived from
ventral mesentery
the liver is covered with visceral peritoneum except at the
bare area
pancreas forms a ___ and ___ pancreatic bud
dorsal and ventral
head of pancreas and uncinate process is which bud of the pancreas
ventral
body and tail of the pancreas is which bud
dorsal bud
failure in fusion of the pancreatic duct system lead to an
accessory pancreatic duct
2nd half of duodenum, jejunum, ileum, and portions of the large intestine are developed from
midgut
midgut structures are vascularized by branches of what
superior mesenteric artery
week 6, midgut elongates, U shaped loop of the gut projects into the umbilical cord
physiological umbilical herniation
within the umbilical cord, the midgut loop forms a ____ and ____ limb
caudal and cranial
________ 90 degree rotation around the SMA occurs bringing the cranial limb to the right and caudal loop to the left
counterclockwise
10 weeks, intestines will return to abdomen and in there rotates an additional ____ around ___ called ____
180 degrees around SMA
physiological midgut hernia reduction
physiological umbilical hernia anomaly: protrusion of abdominal organs without involving the umbilical cord, through a linear defect in abdominal wall
gastroschisis
physiological umbilical hernia anomaly: persistence of the herniated abdominal contents into the proximal umbilical cord
congenital omphalocele
yolk sac is initially wide communication with the midgut that gets compressed into a stalk when folding into cylindrical embryo occurs. the stalk may persist as a diverticulum off the ILEUM or as a cord from the umbilicus. cord may be fibrous or may have a cyst
meckel’s diverticulum
innervation of the hindgut
p/s: pelvic splanchnic S2-S4
sym: superior hypogastric plexus via IMG
hindgut structures are vascularized via
inferior mesenteric artery
week 7, caudal part of hindgut, the ____, is divided by the urorectal septum into the urogential sinus (urethra and bladder) and the rectum
cloaca (closes off anus)
superior 2/3 anal canal derived from
hindgut (columnar epith)
inferior 1/3 anal canal derived from
proctodeum (stratified squamous epith)
what line indicated the zone transition of endoderm to ectoderm where anal membrane once was
pectinate line
what mesentery extends from the lower esophagus to the cloacal region
dorsal
double layer of dorsal mesentery forming an apron that attaches at the greater curvature of the stomach and at the transverse colon is
greater omentum
limited structure that is only found around the liver
ventral mesentery
between the liver and anterior abdominal wall is, ventral mesentery becomes the
falciform ligament
caudal end of falciform ligament becomes the _____ (_____ in adult_ carrying what kind of blood
round ligament of the liver (ligamentum teres)
oxygenated
between the stomach and liver is the
lesser omentum
lesser omentum is comprised of what two adult ligaments
hepatogastric and hepatoduodenal (portal triad)
surrounding the bare area of the liver, ventral mesentery becomes
R an L triangular ligaments and coronary ligament
structures posterior to abdominal wall end up behind the
parietal peritoneum
parietal peritoneum thus becomes
retroperitoneal
kidneys, 3/4 of duodenum, and pancreas are located where
retroperitoneum
what 3 veins drain into the sinus venous
- vitelline veins
- common cardinal veins
- umbilical veins
veins that drain the yolk sac and become portal system
vitelline veins
drains the anterior cardinal vein and posterior cardinal vein, and become the systemic venous system
common cardinal vein
vein that receives oxygenated blood from the placenta. obliterates and becomes the ligamentum teres of the liver
umbilical vein
what are the arteries that supply the yolk sac
vitelline arteries
the vitelline arteries later become
celiac, superior mesenteric, and inferior mesenteric arteries
arteries that carry lesser oxygenated blood obliterate and become medial umbilical ligametns
umbilical arteries
