Development of digestive system Flashcards
Gut tube is formed from rolling of…
endoderm
Tube on top of a tube refers to…
Neural tube superior to gut tube
Lateral folding is seen in what section
Horizontal/transverse
Cephalocaudal folding is seen in what sections
Sagital
Movement of amnionic cavity pinching and closing yolk sac
lateral folding
ANT and POST lateral folding’s fuze, but mid do not. T or F
True
End of lateral and cephalocaudal folding creates…
Lung bud, liver bud, Foregut, midgut, hindgut, allantois
Known as the 3rd/extra embryonic membrane.
Allantois (extends from hindgut) Collect waste
Clinical condition: Heart outside the thorax
Ectopia cordis
Clinical condition: Intestines herniate through abdominal wall.
Gastroschisis
Clinical condition: Failed closure in pelvic region.
Bladder exstrophy
Clinical condition: Bladder, rectum, and anal canal exposed due to failed closure of pelvic region.
Cloacal exstrophy
Foregut gives rise to
esophagus, stomach, liver and pancreas
Midgut gives rise to
duodenum, jejunum, ileum, ascending colon
Hindgut gives rise to
transverse colon to cloacal membrane
What does the endoderm give rise to?
epithelial lining of digestive tract
secretory cells of exocrine and endocrine cells of pancreas
what does the visceral mesoderm give rise to?
Glands, muscle, connective tissue, and other gut all components.
Temporary closer of foregut, sealing primitive oral cavity and pharynx)
Oropharyngeal membrane
Primitive oral cavity
Stomodeum
When does the oropharyngeal membrane rupture?
4th week
Between rectum and upper part of anal canal
Cloacal membrane
Proctodeum
Separates upper and lower anal canal
When does the cloacal membrane break down creating anal opening?
7th week
Respiratory diverticulum/ lung bud forms when
4 weeks old
Separating lung bud from dorsal part of foregut (pharynx)
Tracheoesophageal septum
Lungs, esophagus and stomach develop at the same time. T or F
False. Lungs and esophagus do, but the stomach develops in rotational stages
Rotation of the stomach along the longitudinal axis creates…
curvatures
Rotation of the stomach along antero-posterior axis creates…
fundus and pylorus
greater omentum
Shortly after the 2nd month, the duodenum transitions from being blocked to becoming open. This process is called…
Recanalization
Hepatic diverticulum/ liver bud is formed from endodermal epithelium at what time?
Middle of the third week
Tissue (mesodermal origin) presenting outside the liver bud is called…
Septum transversum
The bile duct is formed by narrowing of…
hepatic diverticulum and foregut
Bile duct gives rise to…
Gallbladder and cystic duct
When is bile formed?
12th week
Cystic duct and hepatic duct join to form…
common bile duct
When do pancreatic islets (of langerhans) develop?
3rd month
When does insulin secretion begin?
5th month
Rapid elongation of the midgut and its mesentery forms…
primary intestinal loop
What artery supplies the midgut?
Superior mesenteric artery
During the 6th week, the primary intestinal loop and expansion of liver creates…
physiological herniation
Failure of physiological herniation returning to the body cavity=
omphaloceles
Layer of mesoderm separating allantois and hindgut
urorectal septum
As the embryo grows, the urorectal septum and cloacal membrane bind. T or F
True
Rectoperineal fistula
no connection to rectum in males
Urorectal fistula
rectum to urethra not anal canal (males)
Imperforate anus
no anus formed (females)
Rectovaginal fistula
rectum to vagina
