FSHN 360 Final Exam Questions And
Answers
fat soluble vvitamins - - correct answer ✅structurally similar to
sterols or FA
micells, passive diffusion, chylomicrons in circulation
circulatory transporters
no membrane transporter
stored/toxic/don't need daily
toxicity is only really true for Vitamin A and Vitamin D to some
extent
vitamin A - - correct answer ✅main form: all-trans retinol
can also be oxidized to retinal (ketone)
or oxidized once more to retinoic acid
sources of vitamin A - - correct answer ✅animal- preformed,
retinyl esters, FA with ester linkage to alcohol
plant- provitamin, carotenoids, metabolized to become active
vitamin A
lecitin retinol acyl transferase - - correct answer ✅enzyme in the
enterocyte that re-esterifies retinol to retinyl ester
,FSHN 360 Final Exam Questions And
Answers
retinyl ester hydrolase - - correct answer ✅enzyme in the GI tract
that hydrolyzes a retinyl ester into retinol and FA
retinyl ester - - correct answer ✅storage form of vitamin A
100 % absorbed
retinol binding protein - - correct answer ✅a protein that is
necessary to transport vitamin A from the liver to other tissues
joins TTR to help retain retinol in circulation
Transthyretin (TTR) - - correct answer ✅protein that is necessary
to help transport vitamin A from the liver to the tissue
joins RBP to help retain retinol in circulation
Beta-carotene monooxygenase - - correct answer ✅enzyme in the
enterocyte that transforms beta-carotene into 2 retinal
beta-carotene - - correct answer ✅plant form of vitamin A
2 retinols linked together
approximately 1/12 becomes active vitamin A
, FSHN 360 Final Exam Questions And
Answers
retinol activity equivalents (RAE) - - correct answer ✅a measure of
vitamin A activity; the amount of retinol that the body will derive
from a food containing preformed retinol or its precursor, beta-
carotene
1 RAE= 1 microgram all-trans retinol or 12 micrograms of beta-
carotene
function of vitamin A - - correct answer ✅visual cycle (retinal),
cellular differentiation (RA), whole body growth (RA), reproductive
function (retinol)
visual cycle - - correct answer ✅a function of Vitamin A
taking retinol and transforming it into 11-cis-retinal in the eye cells,
11-cis-retinal is then combined with opsin to become rhodopsin
which is activated by light to become metarhodopsin
metarhodopsin translates light to the brain via the optic nerve and
then opsin is released and becomes all-trans retinal and the cycle
then continues
opsin - - correct answer ✅protein that combines with 11-cis-
retinal in the eye cells to create rhodopsin
vitamin A deficiency - - correct answer ✅compromised visual cycle
Answers
fat soluble vvitamins - - correct answer ✅structurally similar to
sterols or FA
micells, passive diffusion, chylomicrons in circulation
circulatory transporters
no membrane transporter
stored/toxic/don't need daily
toxicity is only really true for Vitamin A and Vitamin D to some
extent
vitamin A - - correct answer ✅main form: all-trans retinol
can also be oxidized to retinal (ketone)
or oxidized once more to retinoic acid
sources of vitamin A - - correct answer ✅animal- preformed,
retinyl esters, FA with ester linkage to alcohol
plant- provitamin, carotenoids, metabolized to become active
vitamin A
lecitin retinol acyl transferase - - correct answer ✅enzyme in the
enterocyte that re-esterifies retinol to retinyl ester
,FSHN 360 Final Exam Questions And
Answers
retinyl ester hydrolase - - correct answer ✅enzyme in the GI tract
that hydrolyzes a retinyl ester into retinol and FA
retinyl ester - - correct answer ✅storage form of vitamin A
100 % absorbed
retinol binding protein - - correct answer ✅a protein that is
necessary to transport vitamin A from the liver to other tissues
joins TTR to help retain retinol in circulation
Transthyretin (TTR) - - correct answer ✅protein that is necessary
to help transport vitamin A from the liver to the tissue
joins RBP to help retain retinol in circulation
Beta-carotene monooxygenase - - correct answer ✅enzyme in the
enterocyte that transforms beta-carotene into 2 retinal
beta-carotene - - correct answer ✅plant form of vitamin A
2 retinols linked together
approximately 1/12 becomes active vitamin A
, FSHN 360 Final Exam Questions And
Answers
retinol activity equivalents (RAE) - - correct answer ✅a measure of
vitamin A activity; the amount of retinol that the body will derive
from a food containing preformed retinol or its precursor, beta-
carotene
1 RAE= 1 microgram all-trans retinol or 12 micrograms of beta-
carotene
function of vitamin A - - correct answer ✅visual cycle (retinal),
cellular differentiation (RA), whole body growth (RA), reproductive
function (retinol)
visual cycle - - correct answer ✅a function of Vitamin A
taking retinol and transforming it into 11-cis-retinal in the eye cells,
11-cis-retinal is then combined with opsin to become rhodopsin
which is activated by light to become metarhodopsin
metarhodopsin translates light to the brain via the optic nerve and
then opsin is released and becomes all-trans retinal and the cycle
then continues
opsin - - correct answer ✅protein that combines with 11-cis-
retinal in the eye cells to create rhodopsin
vitamin A deficiency - - correct answer ✅compromised visual cycle
