Antioxidants

_____is an important part of the glutathione peroxidase enzyme system. a. selenium b. vitamin e c. beta carotene

a. selenium (think S for Samantha and glutathione is my supplement)

what is the purpose of carnitine? a. transports long-chain fatty acids b. transports short-chain fatty acids c. binds lipids to vitamin e d. redox rxns

a. transports long-chain fatty acids

The mechanism by which selenium opposes oxidation involves __________. neutralizing peroxide molecules so that they cannot form free radicals promoting the storage of triglycerides in adipose tissue preventing oxidation of lipids in cell membranes regenerating vitamin E after it has been oxidized

neutralizing peroxide molecules so that they cannot form free radicals

Vitamin E is critical for athletic performance. adolescent growth. postmenopausal bone health. normal fetal and early childhood development.

normal fetal and early childhood development.

Kashin-Beck disease from too little selenium causes joint deformities. t or f

true

antioxidants can easily donate electrons to calm free radicals. t or f.

true

humans cannot synthesize vitamin c. true or false

true

selenium is an antioxidant. t or f

true

match each cancer cell stage with the definition. initiation promotion progression a. first step, a cell's dna mutates, can be random, inherited, or due to genetics. at this stage may self-repair, self destruct, or be annoyed by the immune system. b. cancerous cells grow out of control c. mutated cell divides

(think of sorority steps) initiation = A promotion = C Progression = B

When a person's diet is deficient in vitamin A, mucus production by epithelial cells increases. T or F

False, decreases

Which statement regarding free radicals is FALSE? a. Free radicals steal electrons from phospholipids found in cell membranes. b. Free radicals can be neutralized by antioxidants. c. Free radicals contain an unpaired electron. d. Free radicals donate electrons to unstable compounds.

Free radicals donate electrons to unstable compounds.

Which of the following is NOT a function of vitamin C? It helps to synthesize tissues. It acts as an antioxidant. It is critical for normal fetal and early childhood development of nerves and muscles. It boosts absorption of iron.

It is critical for normal fetal and early childhood development of nerves and muscles. it does help synthesize tissues, think of collagen production

Which of the following is a critical function of vitamin C? It is required for the formation of collagen. It reduces the incidence, duration, and severity of the common cold. It regenerates glutathione to its antioxidant form. It promotes the conversion of beta-carotene to vitamin A.

It is required for the formation of collagen. Vitamin C does not regenerate glutathione to its antioxidant form, but is regenerated by glutathione. It does not reduce the incidence of the common cold in the general population, nor has it been shown to reduce its severity. It has been shown to modestly reduce the duration of a cold if taken before the onset of symptoms. Cleavage of beta-carotene results in the formation of two molecules of vitamin A; vitamin C is not involved in this process.

Which of the following is not a characteristic of vitamin E? It is used to make collagen. It is a fat-soluble vitamin. It is part a part of very low-density lipoproteins. It is a known antioxidant.

It is used to make collagen. that is vitamin c

Which of the following is a characteristic of vitamin E? It protects the lipid molecules in cell membranes from oxidation. It can be manufactured from beta-carotene. It is a critical component of the glutathione peroxidase system. It enhances the absorption of iron.

It protects the lipid molecules in cell membranes from oxidation. (why there is vitamin e in all our lotions - lipid like)

Vitamin E is considered an antioxidant. T or F

True

Individuals taking anticoagulants are often advised to avoid vitamin E supplements. What is the best explanation for this advice? Vitamin E supplementation increases the risk of erythrocyte hemolysis. Vitamin E supplementation could augment the action of anticoagulants and increase the risk of uncontrollable bleeding. Vitamin E supplementation might cause anemia. Vitamin E supplementation might increase the formation of free radicals in individuals taking anticoagulants.

Vitamin E supplementation could augment the action of anticoagulants and increase the risk of uncontrollable bleeding.

unstable electrons are called __________. they want to steal an electron from somewhere else! a. free radicals b. antioxidants c. redox rxns d. selenium

a. free radicals

Kashin-Beck disease is from too little_____ a. selenium b. vitamin e c. beta carotene d. antioxidants

a. selenium

how to increase vitamin e? eat more nuts canola and sunflower oil have an avocado all above

all above

Beta-carotene is all of the above. a weak antioxidant phytochemical. a provitamin for vitamin A. a carotenoid.

all of the above. Beta-carotene is a weak antioxidant phytochemical in the carotenoid group. The body converts it to retinol; therefore, it acts as a provitamin for vitamin A.

The most biologically active form of vitamin E is __________. beta-tocotrienol beta-tocopherol alpha-tocopherol alpha-tocotrienol

alpha-tocopherol remember because it is "alpha" and this question is ferrel (pherol) so mean

Oxidation is best described as a process in which a carcinogen causes a mutation in DNA. a complex compound is broken apart with the addition of water. an atom loses an electron. two atoms exchange electrons.

an atom loses an electron.

Animal foods have _________ Plant foods have ____________ B-carotene, retinol

animal = retinol ( think of humans/animals putting on face) plant food = b carotene (think of carrots)

a diet rich in antioxidants may help reduce the risk for CVD by: a. causing body cells with mutated DNA to self repair and self destruct b. protecting endothelial cell membranes and reducing inflammation and coagulation c. promoting the synthesis of homocysteine and CRP d. all the above

b. protecting endothelial cell membranes and reducing inflammation and coagulation

Which of the following carotenoids can be converted to retinol in the body? lutein beta-carotene retinol lycopene

beta-carotene

The anticoagulant properties of certain antioxidants may prevent blood vessels from developing _____________, which may in turn result in ________________. atherosclerotic plaque; a heart attack or stroke ROS; cancer blood clots; a heart attack or stroke random mutations; cancer

blood clots; a heart attack or stroke

what are the two main diseases related to free radicals?

cancer cardiovascular disease

yellowing of skin seen in people who consume excess amounts of beta-carotene. carotenosis and carotenodermia scurvy and anemia erythrocyte hemolysis and impaired movement xerophthalmia and hyperkeratosis

carotenosis and carotenodermia

When light energy hits the retina, the retinal changes from a _____ to a _____ configuration. circular; linear beta; gamma cis; trans trans;cis none of these answers are correct

cis; trans

beta carotene is ______ a. a weak antioxidant phytochemical b. a carotenoid c. a provitamin for vitamin a d. all of the above

d. all of the above

Which of the following is a characteristic of vitamin e? a. it enhances the absorption of iron b. it can be manufactured from beta carotene c. it is a critical component to the glutathione peroxidase system d. it protects the lipid molecule in cell membranes from oxidation

d. it protects the lipid molecule in cell membranes from oxidation vitamin e all about the lipids

what is the name of deoxidized vitamin c?

dehydroascorbic acid

Which of the following is NOT a function of vitamin C? collagen synthesis neurotransmitter synthesis enzyme synthesis bile synthesis

enzyme synthesis

Where in the body is selenium contained? in amino acids in the lymph system in adipose tissue in the liver

in amino acids

What are provitamins? inactive forms of vitamins that the body cannot use until they're converted to their active form vitamins with antioxidant properties vitamins with overwhelmingly positive effects when taken in the correct amounts inactive enzymes that become activated with the help of prooxidants

inactive forms of vitamins that the body cannot use until they're converted to their active form

Vitamin A is an antioxidant nutrient critical to body functioning. is a key player in the process by which humans see in the dark. is found in the body in three active forms collectively referred to as retinyl ester-compounds. is a key component of the pigment in rod cells that enables us to perceive black-and-white images.

is a key component of the pigment in rod cells that enables us to perceive black-and-white images. Although vitamin A plays a role in enabling humans to see in dim light, humans cannot see in the dark. we are not nocturnal

Which of the following is a function of selenium? All of these are functions of selenium indirectly assists in the regeneration of vitamin E is part of the structure of catalase is essential for the absorption of dietary iron

is essential for the absorption of dietary iron

A recently identified risk factor for CVD that could be reduced by the consumption of a diet rich in antioxidants is __________. obesity a sedentary lifestyle high HDL levels low-grade inflammation

low-grade inflammation

Which mineral does NOT play a key role in antioxidant enzyme systems? zinc magnesium selenium copper

magnesium

A diet rich in antioxidant nutrients may help reduce the risk for CVD by causing body cells with mutated DNA to self-repair or self-destruct. opposing inflammation and coagulation. all of the above promoting the synthesis of homocysteine and CRP.

opposing inflammation and coagulation. Non-malignant body cells with mutated DNA have internal mechanisms by which they typically self-repair or, if unable to self-repair, self-destruct. This behavior is helpful in avoiding cancer, not CVD.

Antioxidants perform all of the following functions EXCEPT __________. converting free radicals to less damaging substances breaking down fatty acids that have already been oxidized donating electrons to free radicals, thereby stabilizing them oxidizing fatty acids in cell membranes

oxidizing fatty acids in cell membranes

The longest stage in cancer development, during which mutated cells repeatedly divide, is known as progression. initiation. metastasis. promotion.

promotion.

Which is NOT an antioxidant enzyme system? radicalase superoxide dismutase glutathione peroxidase catalase

radicalase

Which form of vitamin A enables the eye to react to changes in light? retinol. retinoic acid. retinal. beta-carotene.

retinal.

The retinoid that has the most significant physiological role in the human body is: retinol. retinoic acid. retinal. beta-carotene.

retinol

The retinoid that has the most significant physiological role in the human body is retinol. retinal. retinoic acid. beta-carotene.

retinol.

The pigment that is responsible for night vision is called __________. retinal rhodopsin gamma opsin

rhodopsin

Keshan disease is a deficiency of which nutrient? iron vitamin C selenium vitamin E

selenium

Your best friend has recently joined the Peace Corps and is working to improve the nutrition of children in Somalia, where she has observed many children suffering from night blindness. What food might she recommend to families to help prevent this condition? whole wheat bread peanut butter orange juice sweet potato

sweet potato

Which of the following nutrients requires the most frequent consumption to ensure adequate body stores? vitamin A vitamin E vitamin C beta-carotene

vitamin C the more you consume te less you absorb

Which of the following does NOT function as an antioxidant? vitamin K beta-carotene vitamin C vitamin E

vitamin K

Deficiency of vitamin A is associated with carotenosis and carotenodermia scurvy and anemia erythrocyte hemolysis and impaired movement xerophthalmia and hyperkeratosis

xerophthalmia and hyperkeratosis Scurvy and anemia occur with vitamin C deficiency, and erythrocyte hemolysis and impaired movement are associated with deficiency of vitamin E. Carotenosis and carotenodermia are synonyms for the yellowing of skin seen in people who consume excess amounts of beta-carotene.