III: Abdominal Cavity I- embryology Flashcards
forms the integument and nervous system
ectoderm
spinal cord and all nerves come from …
ectoderm
proctodeum
primary lining of the anus in deuterostomes
stomodeum
secondary lining of the mouth
what does the mesoderm form?
muscles, muscular walls of the gut tube, and most connective tissue including bones
lining of the gut and most gut derived organs come from…
endoderm
when does the primitive gut tube begin to form?
4 week
what is the future umbilical cord?
omphaloenteric duct or yolk stalk
what does the yolk sac become?
- nourishment immediately after pregnancy before the placenta attaches
- endodermal gut tube and respiratory tract
- its germ cells become the gonads
- blood develops here until the liver is ready
Foregut division
stomodeum (ectodermal) –> first 1/3rd of the duodenum
what separates the stomodeum from the foregut
oropharyngeal membrane
arterial supply to the foregut
celiac trunk
what gut division gives rise to pharyngeal pouches?
foregut
midgut division
last 2/3rd of duodenum –> proximal 2/3rd of colon
arterial supply to the midgut
superior messenteric artery
what does the midgut give rise to?
yolk stalk (attaches yolk sac to embryo)
hindgut division
last 1/3rd of colon —> procotdeum (ectodermal)
hindgut arterial supply
inferior mesenteric artery
what does the hindgut give rise to?
allantosis
recanalization
hollowing out of primitive gut tube
atresia
blockage
stenosis
narrowing
define mesenteries
double layer of peritoneum formed by splanchnic mesoderm which connects organs to the body wall
parietal peritoneum
lines the body wall
visceral peritoneum
lines the guts/organs
where do you see the ventral mesentery?
- coronary and falciform ligament
- lesser omentum (not attached to body wall)
dorsal mesentery
provides mesentery for most abdominal organs you will see in lab
define intraperitoneal
organ suspended in the mesentery
define primarily retroperitoneal
organ always has been external to the peritoneum
define secondarily retroperitoneal
organ developed in the mesentery but is now external
SAD PUCKER
retroperitoneal
Suprarenal glands aorta, vena cava duodenum (2nd and 3rd parts) Pancreas Ureters Colon (asc. and desc.) Kidneys Esophagus Rectum
stomach
intraperitoneal
spleen
intraperitoneal
transverse colon
intraperitoneal
esophagus
primarily retroperitoneal
rectum
primarily retroperitoneal
anal canal
primarily retroperitoneal
kidneys
primarily retroperitoneal
distal 2/3rds duodenum
secondarily retroperitoneal
ascending colon
secondarily retroperitoneal
descending colon
secondarily retroperitoneal
4 main components of the foregut
pharynx
esophagus
stomach
proximal 1/3rd of duodeum
5 outpocketings of foregut
- pharyngeal pouches
- lower respiratory system
- liver
- pancreas
- gallbladder
liver developmentally…
foregut
pancreas developmentally…
foregut
polyhydraminosis
fetus normally drinks amniotic fluid, may see an increase in fluide because the infant is not drinking due to atresia or fistula (connecting tube) between esophagus and trachea
which border of the stomach grows faster?
dorsal border (stomach rotates 90 degrees clockwise while developing)
which vagus nerve is on the ventral surface of the stomach and why?
left vagus
- they also turn with the stomach
pancreas forms from how many buds
2 one ventral (short) and one dorsal (long) which fuse together
spleen derivative
mesoderm in the dorsal mesentery
NOT endodermal derivative!!
5 components of midgut
small intestine (minus first 1/3 of duodenum)
cecum
appendix
ascending colon
proximal 2/3rd of transverse colon (to l. colic flexure)
what direction do the intestines rotate in the midgut?
counter-clockwise around the superior mesenteric a.
what causes secondary retroperitoneal configurations?
rotations of the midgut press organs against body wall where the peritoneum fuses to the dorsal body wall
volvulus
intestine twists around itself
internal hernia
mesentery tangled with intestines inside
5 major components of the hindgut
distal 1/3rd of transverse colon descending colon sigmoid colon rectum superior portion of anal canal
outgrowths of the hindgut
urinary bladder and most of urethra
what divides the allantois and yolk stalk
urorectal septum
- separates cloaca into urogenital membrane and anal membrane
what separates the caudal hindgut from the proctodeum?
anal membrane —> defines the pectinate line
Derivative above the pectinate line? below
above: endoderm
below: ectoderm
drainage and innervation above the pectinate line? below?
above: hindgut
below: abdominal wall
rectovaginal fistula or rectourethral fistula
shit coming out of the wrong holes