Module 7- Part 1 and 2 Flashcards
This is the link for part 1, I made a quizlet for it
https://quizlet.com/_aqo3v2?x=1jqt&i=443okn
Password: vitamins
What are the characteristics of fat soluble vitamins
Dissolves in lipid, requires bile for absorption, are stored in tissues, may be toxic in excess
What is the precursor for vitamin A
Beta carotene
What is vitamin a important for
Reproduction, gene expression, vision, normal development of cells, bone growth and of the body etc
What are the different forms of vitamin A
Retinol, retinal, retinoic acid
How does beta carotene become vitamin A. Is all beta carotene converted into vitamin A
By being cleaved in its center. Not all beta carotene is converted to vitamin A and it’s absorption is not as efficient as vitamin A absorption
What are retinol, retinal and retinoic acid each responsible for
How can they be converted to different forms
Retinol: supports reproduction
Retinal: participates in vision
Retinoic acid: regulates growth ( regulates cell differenciation, growth, immunity
retinol and retinal can be converted into each other (reversible) but retinoic acid can only be made from retinal and is irreversible
What is retinals role in vision
When light is absorbed, retinal changes light from cis to trans which creates an electrical impulse that carries visual information to the brain through the optic nerve
What does retinal deficiency cause
Night blindness, where a person has a hard time adjusting to light
What are epithelial cells
Form skin on the outside of the body and form the mucous membrane on the inside of the body
Functions of retinoic acid
- Cell differenciation: controls gene expression to affect cellular differenciation
- Immunity: indirectly affects epithelial barrier and directly affects immune system
- Growth: cell division and bone remodelling
What does retinal combine with to form rhodopsin
Opsin
What are the consequences of vitamin A deficiency
Risk of infectious disease, night blindness and blindness and more severely death
Also, during deficiency, keratinisation can occur
Vitamin A toxicity
When vitamin A is free to damage cells,
Can have bone and birth defects
Vitamin A sources (carotenoids vs retinoids)
Retinoids come from animal sources (especially liver) and are then transformed to retinol in body, carotenoids come from plant sources and are transformed to retinal in the body
Since vitamin A deficiency is one of the most prevalent in the world, what are some suggestions to decrease these levels
- Eat more vitamin A rich food
- Shots every 6 months
- Fortify food supply
- GMO’s
What are the two subgroups of vitamin E
Tocopherols and tocotrienols. Only alpha tocopherol is maintained in the body
What food sources are vitamin E found in
Vegetable oils, nuts, eggs, wheat germ, whole grains
What is the vitamin E function
Antioxydant, protects polyunsaturated fatty acids and lipids from oxidation as well as protects heart and lungs from oxidation
Is a primary or secondary deficiency more common for vitamin E
Secondary deficiency from fat malabsorption
What would happen during vitamin E deficiency
May interfere with blood clotting of vitamin K activity and cause hemorrhages
What food sources is vitamin K abundant in
Green vegetables, liver and milk
What are the forms of vitamin K
Phylloquinone with dietary fats
Manaquinone: synthesized by colonic bacteria
What are the causes of primary and secondary deficiency of vitamin K
Primary: hemorrhage
Secondary: fat malabsorption
