GI tract overview Flashcards
where does the primordial gut tube develop from
endoderm lining of yolk sac
what is the primordial gut tube split into
foregut
midgut
hindgut
what structures are found in the foregut
Primordial pharynx and its derivatives
Lower respiratory system
Esophagus and stomach
Duodenum
Liver
biliary apparatus (hepatic ducts, gall bladder, and bile duct),
pancreas
what artery and lymph supplies the forgut
celiac
celiac lymph nodes
3 constrictions of the oesophagus
Cervical: – 15cm from incisor teeth (IT)
Thoracic: – crossed by arch of aorta (22.5 fromIT) and left main bronchus (27.5cm from IT)
Diaphragmatic: Where it passes through the oesophageal hiatus of the diaphragm- 40 cm from IT
parts of the stomach
and what does the pyloric sphincter do
controls discharge of contents to duodenum
where is bile
- produced
- transported
- stored/concentrated
- liver
- bile ducts
- gallbladder
what artery supplies gallbladder
and where does it lie
cystic artery
inside the triangle of calot
what doe sthe pancreas release as
exocrine
endocrine
exo = pancreatic juice
endo = insulin and glucagon
what plane does the pancreaslie
along the transpyloric plane L1-L2
what vein formed in relation to the pancreas and where
portal vein
behind the neck
branches of the celiac trunk in foregut
and where they run / supply
1) Left gastric artery – runs along the lesser curvature of the stomach
2) Hepatic artery – supply liver and gallbladder
3) Splenic artery – Runs retroperitoneally along the superior (upper) margin of the pancreas
structures in the midgut
- Small intestine including most of duodenum
- The cecum,
- appendix
- ascending colon
- right half to two-thirds of the transverse colon
what part of the duodenum receives bile and pancreatic duct
second part
how to tell the difference between the jejunum and ileum
basically, ileum had more loops of blood vessels (arcades)
midgut blood supply
and lymph
Superior mesenteric artery
Main branches: Jejunal and ileal arteries
Other branches: Middle colic, right colic and iliocoloic
superior mesenteric lymph nodes
Hind gut structures
and artery
- Left one-third of transverse colon
- descending colon
- sigmoid colon
- rectum
- upper part of anal canal
- Epithelium of the urinary bladder and most of the urethra
•Inferior Mesenteric artery
how is the large intestine different from the small
-
Omental appedices – small, fatty, peritoneal like projections
- Haustra or sacculations- constriction and bulges
- Teniae coli – Thickened bands of smooth muscle (longitudinal layer)
appendix definition
Blind intestinal diverticulum with masses of lymphatic tissue
what is the most common position of appendix
and where is it most painful during infection
Retrocecal
macburneys point
blood and lymph supply of hind gut
Inferior mesenteric artery
Origin: Anterior branch of abdominal aorta (L3)
Branches: Left colic, sigmoid arteries and superior rectal artery
Superior rectal artery is the terminal branch of inferior mesenteric artery
parasympathetic and sympathetic innervation nerves
para = vagus and pelvic splanic nerves S2-4
sympathetic = abdominopelvic splanchnic nerves- greater T5-9, lesser T10-11, and less T12
prevertebral sympathetic ganglia
abdo aortic plexus
what are portocaval shunts
venous enlargement during portal vein obstruction
where can portocaval shunts occur
anorectal junction
gastroesophageal junction
at umbilicus
symptoms of portocaval shunts
haemorrhoids
esophagael varices
caput medusae
3 groups nodes of the lumbar nodes
pre artic
lateral aortic
retro aortic
what nodes are included in the pre aortic group
coeliac
superior and inferior mesenteric nodes
what organs drain into the pre aortic lymph group
organs supplied by anterior branches of aorta
what organs drain into lateral aortic lymph group
organs supplied by lateral aortic branches
what organs drain into retro aortic lymph group
post abdominal wall
