Vitamins Flashcards
Which vitamin is most likely to give you toxicity symptoms
vitamin A
Bioavaliability
the degree to which nutrients can be absorbed and utilized by the body
3 things that can influence bioavaliablity
- present/absence of chronic diseases 2. age 3. alcohol abuse
How can our bodies synthesize and activate vitamin D
cholesterol + UV radiation = vitamin D liver and kidney enzymes activate it.
What is the predominant form of vitamin D found in our food
D2 Ergocalciferol
What happens to 80% of ingested vitamin D
incorporated into micelles
1 cause of non-traumatic blindness worldwide?
Vitamin A deficiency
Distinguish between Retinoids and Carotenoids
Retinoids are the most significant form in our diet and are called pre formed vitamin A because they are already active. Carotenoids have to be converted to Retinoids to be active.
Explain vitamin A absorbtion
- retinyl esters are converted to retinol in SI
- once absorbed, retinol re forms retinyl esters
- retinyl esters are packed into chylomicrons and sent to liver
- liver mobilizes stored vitamin a as retinol + retinol binding protein + transthyretin
- complex binds with retinol binding protein receptors on target cells
- endocytocisis and package with cellular transport protein
- complex binds with RAR/RXR nuclear receptors
- complex interacts with DNA to influence gene expression
3 sx of vitamin A deficiency
- blindness 2. night blindness 3. dry skin
3 sx of vitamin A toxicity
- GI issues 2. visual issues 3. HA
2 functions of vitamin E
- antioxidant 2. cell membrane integrity
2 sx of vitamin E deficiency
- anemia 2. nervous sx damange
2 functions of vitamin k
- coagulation via prothrombin 2. osteocalcin formation
What is the only water soluble vitamin that isn’t a coenzyme
choline
B1
Thiamin
B2
riboflavin
B3
Niacin
B5
Pantothenic acid
B6
Pyridoxine
B7
Biotin
B9
folate
B12
cobalamin
2 Functions of Thiamin B1
- coenzyme TPP 2. neurotransmitter production
2 diseases associated with thiamin defiency
1. beriberi
- muscular wasting
- AMS
- fatigue
2. Werneke-Korsakoff
- AMS
2 functions of Niacin B3
- Coenzyme NAD/NADP
- DNA repair
Disease associated with niacin deficiency
Pellagra
- dermatitis around neck
- AMS
- fatigue
- diarrhea
How can our bodies synthesize niacin
with tryptophan
1 function of riboflavin
conezyme FMN/FAD
disease associated with riboflavin deficiency
Arabiflavinosis
- tongue cracking
- tongue swelling
- mouth swelling
- throat swelling
1 function of pyridoxine B6
coenzyme coA
3 functions of Folate B9
- coenzyme tetrahyrofolic acid
- DNA synth
- nervous sx development
3 consequences of a folate deficiency
- spinal bidifda
- encephaly
- anemia
3 functions of cobalamin
- coenzyme
- maintain the myelin sheath
- homocysteine to methionine
3 sx of cobalamin deficiency
- anemia
- weakness
- AMS
2 functions of choline
- acetylcholine
- phospholipids
1 sx of a choline deficiency
liver damage
2 functions of vitamin C
- coenzyme
- collagin synth (Triple helix)
Disease associated with vitamin c deficiency
Scurvy
- bleeding gums
- decreased immune function
- decreased wound healing
- bruising
Explain vitamin B12 absorbtion
- free B12 binds with R protein from the salivary glands
- in the stomach, HCl and pepsin frees B12 from protein
- B12 leaves the stomach bound to K protein
- In SI, pancreatic protease releases B12 from K protein
- B12 binds with intrinsic factor from parietal cells
- B12/intrinsic factor is absorbed
- B12/intrinsic factor binds with transcobalamin in blood
- enters liver via protal vein
