Lecture 17 Gut Flashcards
What gives rise to the CNS?
- Neural tube
What gives rise to the nucleous palposa?
- noto cord
septum transversum
- becomes the heart
Allantois
- duct that is important in embryonic respiration in embryos that develop in shells (birds)
Foregut gives rise to
- esophagus
- stomach
- gives rise to half of Duodenum (first part of small intestine )
Foregut/midgut transition
- duodenum is identical on both sides but blood supply is different
- arteries supplying duodenum changes at this point
Foregut derived organs
- pancreas
- gall bladder
- Liver
Spleen
- is not derived from foregut
- comes from mesoderm
- Lymphoid organ not digestive
Midgut gives rise to
- 2nd half of duodenum
- jejunum
- illeum
- cecum (L)
- appendix (L)
- asc. colon (L)
- 1st 2/3of transvere colon (L)
Midgut/hindgut transition
- not a boundary in major parts of GI tract
- transition measured by nerve and blood supply
Hindgut
- shortest and simplest part of gut tube
- last 1/3 of transverse colon
- descending colon
- sigmoid colon
- rectum
Accessory organs
- only connected to foregut
What are foregut derivaties supplied by?
- branches of the celiac artery
What are midgut derivatives are supplied by branches of the?
- superior mesenteric artery
- largest
Hindgut derivatives are supplied by branches of the ?
- inferior mesenteric artery
- smallest and simplest
Gut derivatives sensory innervation
- no somatic (internal organs)
- visceral motor
- visceral sensory
Sympathetic innervation
- reached by long splanchnic nerves
- T1-L2
Where are the sympathetic preganglionic cell bodies of the foregut
- T5-T9
- greater splanchnic nerve
- ## celiac (same as artery) (size of quarter)
What is the sympathetic splanchnic nerve that innervates the foregut?
- greater splanchnic nerve
What is the sympathetic prevertebral ganglion that innervates the foregut?
- celiac
- large (same size as quarter)
Sympathetic Postganglionic axons of the foregut follow
- celiac artery
- massive bundle
The sympathetic preganglionic cell bodies of the midgut are?
- T9-T12
What are the sympathetic splanchnic nerves that innervate the midgut?
- Lesser/least splanchnic nerves
What are the sympathetic prevertebral ganglion of the midgut?
- superior mesenteric/intermesenteric
- large ganglia close to celiac