©GRACEAMELIA 2024/2025 ACADEMIC YEAR. ALL RIGHTS RESERVED
FIRST PUBLISH OCTOBER 2024
Final Exam FSHN 360 Study Guide Solutions
fat soluble vvitamins - Ans:✔✔-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 - Ans:✔✔-main form: all-trans retinol
can also be oxidized to retinal (ketone)
or oxidized once more to retinoic acid
sources of vitamin A - Ans:✔✔-animal- preformed, retinyl esters, FA with ester linkage to alcohol
plant- provitamin, carotenoids, metabolized to become active vitamin A
Page 1/20
, ©GRACEAMELIA 2024/2025 ACADEMIC YEAR. ALL RIGHTS RESERVED
FIRST PUBLISH OCTOBER 2024
lecitin retinol acyl transferase - Ans:✔✔-enzyme in the enterocyte that re-esterifies retinol to retinyl
ester
retinyl ester hydrolase - Ans:✔✔-enzyme in the GI tract that hydrolyzes a retinyl ester into retinol and FA
retinyl ester - Ans:✔✔-storage form of vitamin A
100 % absorbed
retinol binding protein - Ans:✔✔-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) - Ans:✔✔-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 - Ans:✔✔-enzyme in the enterocyte that transforms beta-carotene into 2
retinal
beta-carotene - Ans:✔✔-plant form of vitamin A
2 retinols linked together
Page 2/20
, ©GRACEAMELIA 2024/2025 ACADEMIC YEAR. ALL RIGHTS RESERVED
FIRST PUBLISH OCTOBER 2024
approximately 1/12 becomes active vitamin A
retinol activity equivalents (RAE) - Ans:✔✔-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 - Ans:✔✔-visual cycle (retinal), cellular differentiation (RA), whole body growth
(RA), reproductive function (retinol)
visual cycle - Ans:✔✔-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 - Ans:✔✔-protein that combines with 11-cis-retinal in the eye cells to create rhodopsin
vitamin A deficiency - Ans:✔✔-compromised visual cycle
night blindness leading to keratomalacia
stunted growth
infection in GI tract
Page 3/20
FIRST PUBLISH OCTOBER 2024
Final Exam FSHN 360 Study Guide Solutions
fat soluble vvitamins - Ans:✔✔-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 - Ans:✔✔-main form: all-trans retinol
can also be oxidized to retinal (ketone)
or oxidized once more to retinoic acid
sources of vitamin A - Ans:✔✔-animal- preformed, retinyl esters, FA with ester linkage to alcohol
plant- provitamin, carotenoids, metabolized to become active vitamin A
Page 1/20
, ©GRACEAMELIA 2024/2025 ACADEMIC YEAR. ALL RIGHTS RESERVED
FIRST PUBLISH OCTOBER 2024
lecitin retinol acyl transferase - Ans:✔✔-enzyme in the enterocyte that re-esterifies retinol to retinyl
ester
retinyl ester hydrolase - Ans:✔✔-enzyme in the GI tract that hydrolyzes a retinyl ester into retinol and FA
retinyl ester - Ans:✔✔-storage form of vitamin A
100 % absorbed
retinol binding protein - Ans:✔✔-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) - Ans:✔✔-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 - Ans:✔✔-enzyme in the enterocyte that transforms beta-carotene into 2
retinal
beta-carotene - Ans:✔✔-plant form of vitamin A
2 retinols linked together
Page 2/20
, ©GRACEAMELIA 2024/2025 ACADEMIC YEAR. ALL RIGHTS RESERVED
FIRST PUBLISH OCTOBER 2024
approximately 1/12 becomes active vitamin A
retinol activity equivalents (RAE) - Ans:✔✔-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 - Ans:✔✔-visual cycle (retinal), cellular differentiation (RA), whole body growth
(RA), reproductive function (retinol)
visual cycle - Ans:✔✔-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 - Ans:✔✔-protein that combines with 11-cis-retinal in the eye cells to create rhodopsin
vitamin A deficiency - Ans:✔✔-compromised visual cycle
night blindness leading to keratomalacia
stunted growth
infection in GI tract
Page 3/20
