Fat Soluble Vitamins (A, D, E, and K)
Vitamin D can also be known as
1, 25 dihyroxy Vitamin D (calcitriol)
Rhodopsin
A molecule composed of opsin (protein) and cis-retinal (vitamin A)
Keratinization
Accumulation of keratin in a tissue (due to diminished goblet cells in GI tract for mucous production)
Vitamin D must be _____________ before it can function
Activated
Other name for vitamin E
Alpha-tocopherol
Retinyl esters are found in __________ foods
Animal
Chief function of vitamin E
Antioxidant (stabilization of cell membrane, regulation of oxidation reactions, protection of polyunsaturated fatty acids and vitamin A)
Beta-carotene (precursor for Vitamin A) can act as an ___________, capable of protecting the body against disease
Antioxidants
Toxicity symptoms of vitamin E
Augments (increases) the effects of anti clotting medication
What is the precursor of Vitamin A?
Beta-carotene
Acute toxicity symptoms of vitamin A
Blurred vision, Nausea, vomiting, vertigo, increase of pressure inside skull, mimicking brain tumor, headaches
Vitamin A and D play a key role in ____________ ________
Bone growth
Rickets symptoms
Bowing of legs (inadequate calcification), enlargement of ends of long bones (knees, wrists), deformities of ribs (bowed with beads), rapid enlargement of head (delayed closing of fontanel), protrusion of abdomen
Vitamin D is also known commonly as
Calciferol
Vitamin D and ________ in bone growth
Calcium
Foods derived from plants provide __________, some of which can be converted vitamin A
Carotenoids
__________ who are deficient in vitamin A don't grow
Children
Rickets are found in __________, while osteomalacia is found in ________
Children, adults
Precursor for vitamin D is the body's own _________
Cholesterol
As rhodopsin absorbs light, retinal changes from ______ to ______, which triggers an electrical impulse that carries visual information to the brain through the optic nerve
Cis to trans
Cones
Color vision
Vitamin D3
Derived from animal foods in diet
Vitamin D2
Derived from plant foods in diet
Toxicity symptoms of vitamin D
Elevated blood calcium, calcification of soft tissues (blood vessels, kidneys, heart), frequent urination
With help of vitamin A, ___________ destroy selected sites in the bone, removing parts that are not needed
Enzymes
Vitamin A promotes differentiation of ____________ cells and __________ cells, one-celled glands that synthesize and secrete mucous
Epithelial and goblet
These vitamins are less readily ________, and tend to remain in fat storage sites
Excreted
These vitamins are stored in the cells associated with ______
Fat
How do these vitamins absorb?
First into the lymph, then the blood
Significant sources of vitamin A: Retinol
Fortified milk, cheese, cream, butter, fortified margarine, eggs, liver
Previtamin D3 is converted to vitamin D3 with the help of the body's __________
Heat
Vitamin E is easily destroyed by ________ and __________
Heat and oxygen
Vitamin A plays two indispensable roles in the eye
Helps maintain a crystal clear outer window (cornea) and participates in the conversion of light energy into nerve impulses at the retina
Deficiency symptoms of vitamin K
Hemorrhaging
Two __________ reactions must occur for the activation of vitamin D
Hydroxlation
Toxicity disease of vitamin A
Hypervitaminosis A
Toxicity disease of Vitamin D
Hypervitaminosis D
Deficiency disease for vitamin A
Hypovitaminosis A
Without vitamin A, the normal structure and function of the cells in the mucous membrane are __________
Impaired
Chronic toxicity symptoms of Vitamin A
Increased activity of osteoclasts causing reduced bone density, liver abnormalities, birth defects
Softening of cornea
Keratomalacia, softening of cornea that leads to irreversible blindness
90 percent of Vitamin A stores are found in the
Liver
After absorption via the lymph system, vitamin A eventually arrives at the __________, where it is stored
Liver
Osteomalacia symptoms
Loss of calcium causes soft, flexible, brittle, and deformed bones , progressive weakness, pain in pelvis, low back, legs
Chief functions of vitamin D in the body
Mineralization of bones
Vitamin A maintains healthy cells in ________ membranes
Mucous
Hypovitaminosis A deficiency symptoms
Night blindness, corneal blinding, triangular grey spots on eyes, softening of cornea, corneal degeneration and blindness, keratinization
Toxicity symptoms of vitamin K
No toxicity symptoms known
Night blindness
Nyctalopia, slow recovery of vision after flashes of bright light or inability to see in dim light
The liver and kidneys add an ______ group to produce the active vitamin
OH
Vitamin A acts as _________ and __________ for bone remodeling
Osteoclasts and osteoblasts
Vitamin E protects vitamin A from _________
Oxidation
Retinal
Participates in vision
How often should these vitamins be consumed?
Periodically, every few weeks to months
Vitamin K other names
Phylloquinone, menaquinone, menadione, napththoquinone
Beta-carotene is found in _________ foods
Plant
Significant sources of Vitamin E
Polyunsaturated plant oils (margarine, salad dressings, shortenings), leafy green vegetables, wheat germ, whole grains, egg yolks, liver, nuts seeds
Major roles of vitamin A in the body
Promoting vision, protein synthesis and cell differentiation (maintaining the health of epithelial tissues and skin), reproduction and growth
These vitamins require __________ __________ for transportation
Protein carriers
Each cell that uses Vitamin A have special _______ _________ for it, and it's action within each cell may differ depending on the receptor
Protein-receptors
Mineralization of bones
Raises blood calcium and phosphorus by increasing absorption from digestive tract, withdrawing calcium from bones, stimulating retention by kidneys
Deficiency symptoms of vitamin E
Rare, red blood cell breakage (erythrocyte hemolysis), nerve damage
Retinoic acid
Regulates growth
Collectively, these 3 compounds are known as ________
Retinoids
Foods derived from animals provide compounds (retinyl esters) that are readily digested and absorbed as _________ in the intestine
Retinol
Zinc helps regenerate retinal from ___________ in eye
Retinol
___________ participates in sperm development
Retinol
There are three active forms of Vitamin A in the body
Retinol, retinal, and retinoic acid
Other names for Vitamin A
Retinol, retinal, retinoic acid, beta-carotene
What special transport protein picks up vitamin A from the liver and carries into blood?
Retinol-Binding Protein (RBP)
The cells of the retina contain __________
Rhodopsin
Vitamin D deficiencies diseases
Rickets and osteomalacia
The retina contains _______ and _______
Rods and cones
Significant sources of vitamin A: Beta-carotene
Spinach and other dark leafy greens, broccoli, deep orange fruits (apricot, cantaloupe) and vegetables (squash, carrots, sweet potatoes, pumpkin)
Retinol
Supports reproduction
Chief functions of Vitamin K in body
Synthesis of blood-clotting proteins and bone proteins that regulate blood calcium
The body can _______________ Vitamin D, with the help of sunlight, from a precursor that the body makes from cholesterol
Synthesize
Significant sources of Vitamin K
Synthesized in body by GI bacteria, dark green leafy vegetables, liver, milk
Significant sources of Vitamin D
Synthesized in the body with the help of sunlight, fortified milk, margarine, butter, cereals, and chocolate mixes, veal, beef, egg yolks, liver, fatty fish
These vitamins are likely to reach ________ levels when consumed from supplements
Toxic
To make vitamin D, _____________ from sun hit a precursor (7-dehydrocholesterol) and convert to ____________
UV rays, previtamin D3
Rods
Vision at low lifht
The most studied of carotenoids with __________ ____ activity is beta carotene, which can be split to form Retinol in the intestine and liver
Vitamin A
Vitamin D comes in two major forms, __________ and __________
Vitamin D3 (cholecalciferol) and vitamin D2 (ergo calciferol)
Corneal degeneration and blindness
Xerophthalmia
Corneal drying
Xerosis, progressive blindness caused by inadequate mucus production
_______ is needed for Vitamin A's transport protein
Zinc