Digestion and Abs II Flashcards
once lipids are in the enterocyte they are ____ and then packaged into ____
re-esterified, chylomicrons
the chylomicron has a ___ coat over it
lipoprotein
in the liver, the lipids will be made into ____
VLDL, LDL, and HDLs
when you eat a meal, the bile cycles approx. ___ times. It cycles more if ___
3-6 times, there is a lot of fat
in the terminal ilium, the reabsorption of conjugated bile is via _____
secondary active transport with sodium
____ bile can diffuse into the cell because ____
unconjugated, it is lipophilic
____ bile cannot be reabsorbed
secondary
in the jejunum, sodium comes in the cells as ___ goes out. This is possible because of ___
H+, carbonic anhydrase
as Na is absorbed, ___ also comes in to preserve electro-neutrality
Cl-
if iron is in the ____ form, it can diffuse in
hemin
once iron is absorbed, it is ____ for ____ or ____ and ____ to be taken to the ____
bound to ferritin for storage, taken out of the cell by IREG1 and bound to transferrin, liver or bone marrow
we take in ___ of iron per day
3 mg
how do we usually lose iron on a daily basis?
sloughing off of enterocytes
iron is bound because ___
it is toxic
calcium is bound because ____
many systems use it as a 2nd messenger
in the cell, calcium is bound to ____
calbindin
calcium gets out of the cell via ____ and a ____
ATPase, Ca/3Na exchanger
Vitamin D3 helps get calcium into the kidneys and enterocytes by ____ and ___
increasing the binding sites, increasing the Calcium ATPase
___% of calcium in the blood is bound and ___% is free
40%, 60%
in the ____ calcium doesn’t have to be bound, but in the ____ it does have to be bound
blood, cell
in the mouth, B12 is protected by ____
TC-1 (transcobalamin 1)
in the stomach, B12 is protected by ___
intrinsic factor
in the lumen of the small intestine, the trypsin cleaves the ____ of B12, and ___ will bind
TC-1, intrinsic factor
when intrinsic factor binds, the B12 forms a ___
dimer
in the ____ a receptor recognizes the B12 dimer and intercalate it into the cell
terminal ileum
when the B12 leaves the cell, it binds to ___
TC-2
a type of good bacteria, can process plant polysaccharides making products (Vitamin K and biotin) which can diffuse through the intestinal lining
bifidobacteria
_____ can cause infection if abscesses occur and have been implicated in initiation of colon cancer and possibly colitis. These are good at ____
bacteroides, becoming resistant to antibiotics
the highest percentage (___%) of total solids in feces is ____
30%, bacteria
inorganic materials (__) account for ___% of solid waste in feces
calcium and phosphates, 15%
fat accounts for ___% of total solids in the feces and come from ___
5, desquamated intestinal cells
