Digestion 2 Flashcards
what phases can regulation of the stomach be divided into
cephalic, gastric, and intestinal phases
describe what happens during cephalic regulation
thinking or smelling food
secretion of acid happens sometimes even before food enters the mouth
why does secretion of acid happen sometimes before food enters the mouth
stomach churns due to habituation of getting food
due to vagus nerve and parasympathetic (long reflex)
what is an example of something that triggers cephalic regulation
depression can cause loss of appetite and inhibit digestion
describe when gastric regulation occurs
several hairs after eating food
describe what happens during intestinal regualtion
occurs in the intestines
primarily inhibits digestion due to enough food in intestine (slows food emptying)
gastric inhibitory peptide
what does the stomach act as a gatekeeper for
intestine
what does it mean for the stomach to be a gatekeeper for intestine
prevent intestine from having too much food at once
stomach has ability to store food for a little bit unlike intestine
why do you not want to overload intestine
it is where absorption happen
how often does small bolus go into the small intestine
every 3 minutes
what is suited for chemical digestion and absorption
small intestine
what does the small intestine have a large amount of
surface area due to the layers of folding
what finger like projection is on each fold of the small intestine
villi
what does the villi do
creates surface area
what grabs amino acids and transports them across membrane into the blood
absorptive cells
what do the goblet cells do
secretes mucus to get food liquefied and moving along
what has a rich blood supply
interior of villus
where does digestion of proteins begin and end
begins in the stomach and is completed in the small intestine
what is the enzyme of the stomach that breaks down protein
pepsin
what enzymes are found in the lumen of the small intestine
pepitadases and trypsins
what do pepitadase and trypsin send to the brush border enzymes on epithelium
short trains of amino acids(2 or 3)
what happens at the brush border in the digestion of proeins
finish the job, take short train and split the bonds
then amino acids are immediately absorbed in the blood
where does digestion of carbohydrates begin and end
begins in the mouth and ends in the small intestine
the digestion of what is water soluable
proteins
what enzyme in the stomach breaks down carbohydrates
no enzymes in stomach
what breaks down carbohydrates
salivary amylase
what is found in the lumen of the small intestine that helps break down carbohydrates
intestinal amylase
do the brush border enzymes have the same function in the digestion of proteins and carbohydrates
yes, in both they finish the job of breaking down and absorb the subsequent sugars and amino acids into the blood
where does digestion of lipids occur and what is it facilitated by
it occurs in the intestine and is facilitated by bile
what is the function of the digestion of lipids
process to break apart big globs of fat
the digestion of what is not water soluable
lipids
what allows for the emulsification of fats
bile
what allows chemical digestion by lipases
emulsification of fats
what does fatty chyme release
CCK
what coordinates fat digestion
CCK
liver releases bile to the _______
gallbladder
what stimulates the gall bladder to release bile
CCK
this is the break down of large flat globules into small droplets
emulsification
what do lipases chemically digest lipid into
fatty acids and glyceral
where are fatty acids and glyceral absorbed into
lymph lacteal for drainage
what neutralizes the acidic chyme in the small intestin
secretin
whats main target is the pancreas
secretin
what does the pancreas do
secretes enzymes and HCO3 into the small intestine
makes products that small intestine needs for digestion
what does the pancreas facilitate and how
digestion in small intestine by secreting bicarbonate(pH8) which is stimulated by secretin
how long does the pancreas continue to make bicarbonate
until the chyme is neutralized to pH7 int the duodenum
what are the enzymes of digestion for the duodenum stimulated by
CCK
