GI Flashcards
(135 cards)
what is in the upper gi tract?
mouth, esophagus, stoamch
What are the four functions of the gi system?
ingestion, digestion, absorption, elimination
what is in the middle gi tract
small intestine
what is amylase
helps breakdown larger polysaccharides into smaller sugars and dextrins
secreted by the parotid gland
what is in the lower gi tract?
caecum, colon, rectum
peritoneum
one continuous thin membrane that lines the abdominal cavity
supports abdominal organs
highly vascularized
lots of lymphatics
parietal peritoneum
outer layer attached to abdominal wall
peritoneal cavity
serous
sterile
comes into contact with lymphatics and blood
visceral peritoneum
inner layer wrapped around organs
cells secrete fluid to help keep organs slide freely past one another
esophagus
posteriort o trachea
propel food into stomach
only part of upper gi tract where no enzymes are secreted
upper esophageal shpincter
prevent air from entering the esophagus
aspiration of gastic contents back into the mouth
lower esophageal sphincter
controls passage of food into stomach
prevents reflux of gastric contents
your patients medical history included GERD. What is the pathophysiological abnormality?
lower esophageal sphincter incompetence
risk of upper gi bleed
cancer of essophagus
ulcers
Serosa
part of the visceral peritoneum
secretes serous fluid
muscularis
longitudinal and circular
stomach additional layer
muscle layer that helps mix chyme and propel it forward
what are the four layers of the stomach from outer to inner
serosa
muscularis
submucosa
mucosa
submucosa
blood vessels
lymphatics
when erosion through the mucosa can lead to bleeds here
mucosa
tight epithelial junctions
barrier to bacteria and other molecules
layer right against food and gastric contents
when tight junctions loosen, there is erosion which can lead to ulcers
secrete mucous to help protect the wall from the acidity of the gi contents
ruggae
coarse folds that expand and contract to help digest foods without increasing pressure
secretes acid
what are the functions of the stomach
temporary storage and mixing of chyme regulated emptying of gastric contents hematostatin inhibits the release of gastrin secretes substances for digestion releases gastrin and somatostatin
gastric secretions
hydrochlorioc acid pepsin (helps break down protein) mucous (with bicarb to neutralize acid) intrinsic factor (for b12 absorption) gastrin(promotes growth gastric mucousa)
parts of the small intestine
duodenum (extends to ligament of treitz)
jejunum
ileum
primary function of small bowel
nutrient absorption
talk about how small intestine digests carbs, proteins, fats, vitamins, minerals and water
proteases from pancrease to break down proteins
carbs get further broken dow
bile helps break down fats (produced in liver, stored in gallbladder)
water soluble vitamins and minerals and water passively reabsorb