VITAMINS Flashcards
Vitamins are (essential or non-essential?) nutrients needed by the body in (small or large?) amounts to maintain normal bodily functions.
essential
Small
It is important to know that deficiencies of these vitamins ____________________________ while excess of vitamins may ________________
prevent the body from operating at full capacity
be damaging to the health.
Too many vitamins will be _________ or ________ , and an excess can be _____.
excreted or stored
Toxic
Classification of vitamins fall into two categories: 1. _______-soluble and 2. ____-soluble.
water
Fat
The water-soluble vitamins – _____ and ________ vitamins – ______ in water before the body can absorb them.
C and the B-complex
dissolve
Fat-soluble vitamins –________________– dissolve in ____ and can be stored in the ________ and ________ until needed.
A, D, E, and K
fat
liver and fat tissue
Characteristics of Fat Soluble Vitamins
Storage: Fat-soluble vitamins are stored in the ______________
Longevity: Fat-soluble vitamins last (shorter or longer?) in the body, because _______________.
liver and fatty tissue.
Longer
they are not needed every day
Characteristics of Fat Soluble Vitamins
Absorption and Excretion: The fat-soluble vitamins are absorbed through the __________ with _________ and are excreted (slowly or rapidly?) .
Toxicity: Because fat-soluble vitamins are _______________________________ they are more likely to cause toxicity, since the body cannot excrete them quickly enough.
small intestine
dietary fat ; Slowly
stored longer in the body’s fatty tissues and liver,
In general, a healthy diet will not cause toxicity, but ___________________ may create an imbalance of vitamins and cause illness.
taking supplements at high levels
Mechanism of action of fat soluble
vitamins
Fat-soluble substances dissolve in fat and are absorbed by the body through the _______________ (tubes that manage the fluid levels in the body).
lymphatic system
Mechanism of action of fat soluble
vitamins
Fat-soluble substances are stored in the __________________ and are eliminated from the body at a (slower or faster?) rate than water-soluble substances.
liver and adipose tissue
Slower
Mechanism of action of fat soluble
vitamins
These vitamins are stored in the body’s fatty tissues and liver, and can ____________ if consumed in excess.
accumulate to toxic levels
Mechanism of action of fat soluble
vitamins
They are absorbed along with ________ in the ________
dietary fat
small intestine.
Functions of Fat Soluble Vitamins
Vitamin A helps with good ____, ______ and ________ systems.
It is essential to ____ growth and ____ development.
It also keeps the _____ ,_____, and _______ working properly.
vision
immune, and reproductive
bone; tooth
heart, lungs and kidneys
Functions of Fat Soluble Vitamins
Vitamin D, along with ______, keeps the ________ by preventing diseases such as_______ ,________
Vitamin D also helps the _____ move, improves the ______ function and helps reduce __________.
calcium
bones strong
rickets, osteoporosis.
muscles; immune; inflammation
Functions of Fat Soluble Vitamins
Vitamin E acts as an ________[ that protects the body from _________ .
It also boosts the _____ system and keeps blood _______________
antioxidant
free radicals
immune
moving through the blood vessels without clotting.
Functions of Fat Soluble Vitamins
Vitamin K, conversely, allows ____________. It also helps the body by making proteins for _________________
the blood to clot
healthy bones and tissues.
rickets, a disorder that causes bones to _______________________
osteoporosis, which makes the bones _________________________
become soft and weak in children
weak and more likely to break.
Fat-soluble vitamins and minerals act as antioxidants, and play a role in bone health, blood clotting, and immune function.
T/F
T
Fat-soluble vitamins and minerals
They function primarily as ___________ of __________ and ________ .
regulators of gene expression and cell differentiation
Regulation of gene expression includes a wide range of mechanisms that are used by cells to ____________________ the production of _____________(protein or RNA)
increase or decrease
specific gene products
Vitamin A (Carotenoids and Retinols)
It occurs naturally only in foods of ________________ origin.
animal and plant
Vitamin A (Carotenoids and Retinols)
Animal sources include ____, butter, whole milk, and egg yolks.
Sometimes the body converts certain _______, especially __________, to vitamin A.
liver
carotenoids
beta- carotene
Vitamin A (Carotenoids and Retinols)
Plant sources are ______________ in colour.
Examples are mangos, papaya, carrots, cantaloupes, sweet potatoes and maize.
Another good source of vitamin A is _______
orange or yellow
red palm oil.
Vitamin A (Carotenoids and Retinols)
Only _____ of the more than ____ naturally occurring carotenoids have provitamin A activity
50
500
It is important to note that:
_______ is one of the most active, usable form of vitamin A.
__________ are present in dark-green vegetables.
Retinol
Carotenoids
Carotenoids are present in __________ vegetables.
dark-green
Carotenoids are also present in yellow and orange fruits and vegetables.
T/F
T
The two ________ rings in beta-carotene are joined by a _________ to form _________
beta ionone
poly-prenoid chain
All-trans retinal
Vitamin A is converted to ______,______, and _________
retinol, retinal and retinoic acid
retinol, retinal and retinoic acid
______ to ______ is reversible
_____ to _____ is one-way
Retinol to retinal
Retinal to retinoic acid
When carrot is eaten, it gets absorbed along side with ____ in the _______. Beta-carotene is metabolized in the ______
Beta-carotene cleaved with an enzyme known as ———— and produced ______ which is absorbed along with fat and goes into the _____ to be stored as _______
fats; small intestine
small intestine.
Di-oxygenase; retinal
liver; RETINOL PALMITATE
Retinol palmitate is released into the ______ when needed and it is carried by _________________ to where it is needed.
blood
retinol binding proteins (RBP)
Functions of vitamin A
Vitamin A helps form and maintain healthy teeth, skeletal and soft tissue, mucus membranes, and skin.
Vitamin A promotes good _____, especially in ____ light.
eyesight
Low
Functions of vitamin A
It is also known as retinol because it _________________________________________
produces the pigments in the retina of the eye.
Vitamin A deficiency and vision loss
G-protein coupled
rod
primary photoreceptor
Vitamin A deficiency leads to Nyctalopia
T/F
T
Rhodopsin
A light sensitivity of rhodopsin leads to a _________ in rhodopsin
conformational change
Rhodopsin
The key __________ in rhodopsin upon photoactivation are the ___ward tilting of the _______ end of ________
conformational changes
out; cytoplasmic; helix 6.
In the absence of light, rhodopsin is Inactivated.
T/F
F
In the absence of light, rhodopsin is activated.
The body synthesizes rhodopsin from vitamin ___, which is why a deficiency in vitamin ___ causes _________
A,
A
poor night vision.
In case of malabsorption
It is recommended to administer ______ units per day of Vitamin A injection intra________ for ____ days; followed with _____ units per day for ______, to be followed with oral therapy
100,000
muscularly
3
50,000
2 weeks
Pharmacokinetics of Vitamin A
Peak plasma concentration= ________
Elimination half-life= _____-_____
4hours
50-100days
Signs of deficiency of vitamin A
_________
Decreased _____________
Extremely ____ skin, hair or nails
Night blindness
resistance to infections
dry
Symptoms of vitamin A toxicity
Symptoms of vitamin A toxicity include dry, itchy skin, headache, nausea, and loss of appetite.
Signs of severe overuse over a short period of time include ______,________, and _______
Vitamin A toxicity can also cause severe _______ and may increase the risk for ________ and _______
dizziness, blurred vision and slowed growth.
birth defects
bone loss and hip fractures.
Vitamin D
The active form of vitamin D promotes _________ of ____________________ and influences _____________.
intestinal absorption of calcium and phosphorus
bone mineralization
Vitamin D
It occurs in two forms:
1. Vitamin D2 (______calciferol)
2. Vitamin D3 (_____calciferol)
ergo
Chole
Vitamin D
It occurs in two forms:
1. Vitamin D2 is produced commercially by _________ gotten from the _____ known as __________
- Vitamin D3 is formed by the action of __________ on the (precursor is _______________) on the ____.
ultraviolet (UV) irradiation ; plant; sterol ergosterol
sunlight
7-dehydrocholesterol; skin
Vitamin D
Interestingly, the human body utilizes both forms of vitamin D by _______ first the ___-position in the ____ and then the ____-position in the ______, producing the biologically active ______________
hydroxylating; 25; liver
1-Alpha; kidney
1,25- dihydroxycalciferols.
hydroxylation describes a chemical process that introduces a _________ into an organic compound.
hydroxyl group (−OH)
Vitamin D occurs naturally in ______ foods such as ___, butter, _____ fish (fish containing __________________ or ___________ ), and egg yolks.
animal
Liver ; fatty
high levels of cholesterol or fatty acids as glycerides
Vitamin D
The amount of vitamin D formed by exposure of skin to sunlight depends upon the ___________, the ______, which can be diminished by atmospheric pollution, and _________
length of the UV irradiation
intensity; skin pigmentation.
Vitamin D
______ skin may have diminished capacity to synthesize vitamin D.
Aging
Functions of vitamin D
Vitamin D promotes ______ in the gut.
It maintains adequate serum ________________
calcium absorption
calcium and phosphate
Functions of vitamin D
It maintains adequate serum calcium and phosphate concentrations
This process enables normal _________________ and prevents involuntary __________ (hypocalcemic _____), leading to ________ and ________
bone mineralization
contraction of muscles ; tetany
Cramps; spasms
Vitamin D deficiency can lead to a loss of bone ______, which can contribute to _________ and __________(broken bones).
density
osteoporosis and fractures
Severe vitamin D deficiency can also lead to other diseases: In children, it can cause _______.
rickets
Rickets is a rare disease that causes the bones to become ______ and ______
soft and bend.
The main consequence of vitamin D toxicity is a _________________, which can cause nausea and vomiting, weakness, and frequent __________.
Vitamin D toxicity might progress to ________ and ______ problems, such as the formation of ________.
buildup of calcium in your blood (hypercalcemia)
urination
bone pain and kidney
calcium stones
Mechanism of action of vitamin D
Vitamin D in coordination with _________ and __________ regulates serum calcium levels by:
_____easing calcium absorption from the small intestine.
parathyroid hormone and calcitonin
incr
Vitamin E
Vitamin E is an important _______ that is thought to protect _________________ from oxidative destruction in cell membranes.
antioxidant
polyunsaturated fatty acids
Vitamin E activity in foods is due to the presence of _______ and _______—compounds of _____ origin.
The most important of these is
____________ ; less active are _________, ___________ , and __________.
tocopherols and tocotrienols
plant
Alpha-tocopherol
Beta-tocopherol
Gamma-tocopherol
Alpha - tocotrienol
Functions of vitamin E
Vitamin E helps maintain _________________
It strengthens the body’s ________ against illness and infection (the immune system).
healthy skin and eyes.
natural defence
___________ are the richest source of vitamin E.
Other good sources include nuts, seeds, whole grains, and wheat germ.
Vegetable oils
The vitamin E content of animal foods is generally (low or high?) .
Low
The foods with high levels of __________ also have a high vitamin E content.
Polyunsaturated fats
Vitamin E deficiency can cause _____ and _________ that results in loss of feeling in the arms and legs, loss of body movement control, muscle weakness, and vision problems.
Another sign of deficiency is a _______________
nerve and muscle damage
weakened immune system
Vitamin K
Vitamin K is needed in the ____ for formation of several ____________
liver
blood clotting factors.
Vitamin K
Vitamin K1, (________) is synthesized by _______, whereas vitamin K2 homologs (_________) are synthesized by ______.
phylloquinone; plants
menoquinones; bacteria
Vitamin K
The human body can obtain vitamin K from ______ sources as well as through synthesis by the ___________
dietary
gut microflora.
Functions of vitamin K
Vitamin K helps to make various proteins that are needed for blood clotting and the building of bones.
T/F
T
Functions of vitamin K
___________ is a vitamin K-dependent protein directly involved with blood clotting.
________ is another protein that requires vitamin K to produce healthy bone tissue.
Prothrombin
Osteocalcin
Sources of vitamin K
• Phylloquinone. __________ including collard and turnip greens, kale, spinach, broccoli, Brussels sprouts, cabbage, lettuces. Soybean and canola oil. Salad dressings made with soybean or canola oil.
• Menaquinones.______ (________________s) Smaller amounts in _____, cheese, eggs.
Green leafy vegetables
Natto
meat
Larger amounts of vitamin K are present in _______________; lower levels are found in cereals, dairy products, meats, and fruits.
dark-green leafy vegetables
Vitamin K deficiency can contribute to significant _______, poor ________, osteoporosis, and increased risk of ________
bleeding
bone development
cardiovascular disease.
Vitamin K toxicity is common
T/F
F
Vitamin K toxicity is extremely rare
These water soluble vitamins are not as likely to reach toxic levels. But ______,______,_______,______, and __________ have upper consumption limits.
niacin, vitamin B6, folate, choline, and vitamin C
