Embryo of GI system Flashcards
How is primitive gut tube formed?
incorporation of yolk sac into embryo during cranial-caudal and lateral folding
from the primitive gut tube, what is formed from the endoderm?
epithelial lining and glands of mucosa
what does recanalization follow?
epithelial lining of gut tube proliferating rapidly and obliterating the lumen of the gut tube
what is derived from the mesoderm in the GI tract?
lamina propria, muscularis mucosa, submucosa;
muscularis externa, adventitia/serosa
What are divisions of the primitive gut tube?
foregut, midgut, hindgut
What is the artery, PANS, SANS of the foregut?
celiac artery;
PANS=>vagus nerves;
SANS=>greater splanchnic nerves- T5-T9
What is the artery, PANS, SANS of the midgut?
superior mesenteric artery;
PANS=> vagus nerves
SANS=>lesser & lowest splanchnic nerves-T9-T12
What is the artery, PANS, SANS of the hindgut?
inferior mesenteric artery;
PANS=> pelvic splanchnic nerves;
SANS=> lumbar splanchnic nerves - L1-L2
What are derivatives of foregut?
esophagus, stomach, duodenum;
liver, pancreas, biliary apparatus, gall bladder;
pharyngeal pouches, lungs, thyroid
what is unique about the pharyngeal pouches, lungs, and thyroid of the foregut?
derived from foregut but => not supplied by celiac artery, vagus, greater splanchnics
What is the spleen associated with?
foregut due to celiac artery being supplied
What are the midgut derivates?
duodenum (2nd, 3rd, 4th); jejunum; ileum;
cecum; appendix;
ascending colon; transverse colon (prox. 2/3)
What are the hindgut derivaties?
transverse colon (distal 1/3);
descending colon; sigmoid colon;
rectum; anal canal (above pectinate line)
define referred pain of the GI system
stimulation of visceral pain fibers that innervate a GI structure resulting pain being felt over T5-L1 dermatomes
What do the sites of referred pain mean?
correspond to spinal cord segments that provide sympathetic innervation to affected GI structure
