vitamins lecture 3 Flashcards
what are the examples of Fat soluble vitamins?
A, D3, D2, E,K
what is an example of vitamin A?
retinol
where is the fat soluble vitamins absorbed in?
SI
what are FSV?
antioxidant
where do the FSV dissolve in?
lipids
where do the FSV circulates in?
lymph
where do the excessive FSV accumulate in?
liver and adipose
what is an active form of vitamin A?
retinal and retinoic acid
where are the vitamin A stored in?
liver
what are the functions of vitamin A?
synthesis of RNA
embryonic development
reproduction
what are the two types of vitamin A?
retinoids
carotenoids
what are the e.g. in retinoids?
retinol
retinal
retinoic acid
what are the e.g. in carotenoids?
provitamins A
nonprovitamins A
what are retinol?
they are preformed vitamin A that can be synthesised from retinal.
what can retinal be converted to?
retinoic acid
what is the regulation of vitamin A?
chylomicrons- lymph- thoracic duct-blood(muscles, adipose, eyes), then the unused vitamin A will go to the liver.
what are the sources of vitamin A:
lutein
lycopene
beta carotene
if you intake appropriate amount of lutein what does it result to?
decreased growth of breast tumours
decreases muscle degeneration
what food are examples of lutein?
dark, green leafy vegetables.
if you intake appropriate amount of lycopene which does it result to?
decreases risk of prostate cancer
what are the examples of lycopene?
tomatoes, grapefruit and apricots
what are the examples of beta carotene?
carrots and sweet potatoes
what disorders does deficiency in vitamin A cause?
night blindness/ nyctalopia
increased risk of infections
xerophthalmia
hyperkeratosis.
what does what is night blindness caused by?
deficiency in retinal
what are the two examples of toxicity in vitamin A?
carotenoid toxicity
retinoic acid/isotretinoin
what are the negative effects of carotenoid toxicity?
blurred vision
liver abnormalities
reduce strength in the bones
birth defects
risk of lung cancer
hypercarotemia
what are the negative effects of retinoic acid/ isotretinoin toxicity?
reduced size of sebaceous glands - decreases oil production
improves ance
what is an example of vitamin D?
cholecalciferol
what is the deficiency caused by Vitamin D?
rickets
what are the functions of vitamin D?
exposed to sunlight vitamin D synthesised to the skin
regulates the absorption of Ca2+ during bone formation.
enhances the immune system
improves muscle strength
what hormone is vitamin D activated by?
parathyroid hormone
what is an example of vitamin E?
Tocopherol
what deficiency is caused by deficiency of vitamin E?
hemolysis and anaemia
oxidative degradation of polyunsaturated membrane phospholipids.
what is the function of vitamin E?
synthesised by plants
most found in fatty tissues
antioxidant properties
provide integrity to the membrane
what does antioxidant property in vitamin E do?
reduces division of oxygen reagents and free radicals
protects polyunsaturated fatty acids in membrane phospholipids from oxidative damage
what is an example of vitamin K ?
menaquinone
what are the types of vitamin K?
K1
K2
what are vitamin K1 synthesised by?
plants
what are vitamin K2 synthesised by?
gram positive bacteria in ileum and jejunum
what is vitamin K2 needed for?
synthesis of zymogens for blood clotting.
what are the functions of vitamin K?
normal blood clotting
provides bone structure
cell signalling
lipid metabolism
what do vitamin K do ?
carboxylates and activates clotting factors
what are vitamin K essential for?
post translation modifications
what are the deficiency caused by vitamin K ?
clotting disorders
decreased bone mineral density
menorrhagia
