GI Digestion and Absorption Flashcards
where are bile salts absorbed
distal ileum
what is affected if there is an inflammatory condition in the terminal ileum
bile salt absorption, B12 absorbtions
what is the function of plicae circularis
slows down chyme
what is the effect of dietary fibers on cholesterol
increase excretion (bind to bile salts)
how come salivary amylase doesnt work in stomach
does not work in acidic pH
pancreatic amylase hydrolyzes starch and glycogen to
maltose
at what pH does pancreatic amylase work
neutral
can intestines digest disaccharides
no
what transporters are used to absorb glucose and galactose
SGLT1 (also need Na) secondary active
how is fructose absorbed
carrier mediated (NOT NA DEPENDENT)
sugar absorbed is moved to the
liver
is disaccharide deficiency congential or aquired
could be either
90% of lipid intake is
Triglycerides
DHA and ERA are essential for
development of vision in newborns
acid lipase breaks down
median chain FA, essential for infants
what does pancreatic lipase do
Hydrolysis of TG to 2 FA and 2-monoglyceride
what does pancreatic colipase do
binds to lipase and allows lipase to the oil interphase, allows better interaction and counteracts bile salt inhibition of lipase
what is the major pancreatic enzyme for digesting
Phospholipase A2;
cholesterol ester is hydrolyzed by ________ to make cholesterol + FA
pancreatic cholesterol esterase
T/F bile salts are water soluable
T
How do bile salts aid in fat absorption
emulsification of fat droplets and lipids
_________ decreases intestinal absorption of cholesterol
ezetimibe
where are MG and FA resassembled to TG
SER
chylomicrons transport ______, VLDL transport ______
fat, cholesterol
most medium and shortchain FAs are transported via
hepatic portal route
what is APO A-1 needed for
LCAT, creates cholesterol ester
what are the major APO proteins
A-1, A-IV, B
pancreatic or bile salt deficiency results in
fat in stool (steatorrhea)
poor fat absorbtion results in a deficiency of which vitamine
ADEK
what is abetalipoprotinemia
no APO-B, cant make chylormicrons or VLDL, accumulation of lipid droplets in cytoplasm of enterocytes
Lack of APO B is caused by a deficiency in
MTTP
what is the effect of VIP on contractions? secretions?
negative, postitive
what is the effect of gastrin on motility? Ach?
stim contraction, stim strength of contract
pancreatic endopeptidase that splits basic AA
trypsin
pancreatic endopeptidase that attacks aromatic
chymotrypsin
pancreatic endopeptidase that attack neutral aliphatic
elastase
pancreatic exopeptidase that attack neutral aliphatic or aromatic
carboxypeptidase A
pancreatic exopeptidase that attack basic AA
carboxypeptidase B
intestines only absorbs what peptides
mono, di, tri
________rapidly dimmensish leakiness of fetal intestine
clostrum
T/F intact IgG absorbtion is a mode of passive immunity
false
gastritis, resection makes poor digestion of
collagen
hartnup disease is defective carrier of
neutral AA
cystinuria involves defective carrier of
basic AA, and cysteine
hartnup and cystinuria can be treated with
dipeptides
vitamin A, what you get, absorption, storage, def
retinol passive immunity, stored in liver
deficiency -night blindness and skin lesions
Vitamin D absorption, what its used for, def
passively absorbed, incorporated to chylomicrons, def causes rickets, osteomalacia
vitamin E transportation, def
lipoproteins and RBCs def-fragile RBC
Vitamin K derivation, usage, deficienct
vegetables, chylomicrons, bleeding disorder
which does not need chylomircons
vitamin E
Niacin what it does, required for, def
reduces plasma cholesterol, oxidation-reduction reaction, def-Dermatidis, Dementia, Diarrhea
B6 defieincey
anemia
how is folic acid uptaken and what is deficiency
facilitated transprt, magablastic anemia
B12 location of absorbtion, defi
terminal ileum, pernicious anemia
