Vitamin A (Retinol) Flashcards
Vitamin A is a ____ carbon lipid molecule obtained in the diet either directly or indirectly from ______________
20/B-cartoene
when b carotene is cleaved what forms
vitamin A1(retinol)
when the oxidation of alcohol to aldehyde of vitamin a1 (retinol) forms:
11-cis-retinal (visual pigment)
when 11-cis retinal is exposed to visible light it forms
all trans retinal which is a neual signal to brain
when the aldehyde of 11 cis retinal is oxidized to acid it forms?
retonic acid which is a hormal signal epithelial cells
what is the function of retinoic acid?
is a singal compound that binds to receptor proteins inside the cells,
the ligand-receptor complexes binds then to chromosomes and regulate gene expression during cell differentiation
what is the function of retinal
light senstive compound (As said earler) so important in vision
retinal is a prosthetic group of the protein rhodopsin
absorption of photon of light by retinal triggers a neural impulse
what are dietary sources of vitamin A?
1 oily fish
2 liver
3 eggs
4 whole milk
5 butter
what are dietary sources of b carotene
1 carrots
2 sweet potatoes
3 yellow vegtables
what happens in the defeciency of vitamin a
1 dryness of the skin, eyes and mucous membranes
2 retarted development and growth
3 night blindness
4 tendencay to form inflammation
Toxicity primarily affects central nervous system and results in ________, ___________, _________, ____________.
ataxia, anorexia,sickness, headache
what is heptamegalia?
histological changes in the liver
what is hyperlipidemia?
thickness in long bones
what is hypercalcemia?
dryness in skin
what happens when a pregnant uses lots of vitamin A
affects the fetus development and cause malformations
