Ch 10 Flashcards
The gaining of electrons by an atom during metabolism is called:
A) oxidation.
B) reduction.
C) radiation.
D) mineralization.
B) reduction.
Which of the following statements is TRUE regarding free radicals?
A) Free radicals are formed as a by-product of healthy metabolism.
B) Our body has no mechanism to combat free radicals.
C) Exposure to pollution decreases free radical production.
D) A free radical is an atom with paired electrons in its outermost shell.
A) Free radicals are formed as a by-product of healthy metabolism.
Which of the following statements about antioxidants is TRUE?
A) Antioxidants are formed in the body.
B) Antioxidants oxidize free radicals.
C) Antioxidants reduce free radicals by removing an electron.
D) Antioxidants donate an electron, thus reducing the free radical.
D) Antioxidants donate an electron, thus reducing the free radical.
Which antioxidant enzyme system functions by removing hydrogen peroxide from the body by converting it into water and oxygen?
A) superoxide dismutase
B) catalase
C) glutathione peroxidase
D) microsomal enzyme-oxidizing system
B) catalase
Which of the following are required components of many antioxidant enzyme systems?
A) antioxidant minerals
B) antioxidant vitamins
C) phytochemicals
D) gastrointestinal microflora
A) antioxidant minerals
From what source does our body obtain the majority of its antioxidants?
A) from sunlight
B) from the by-products of healthy metabolism
C) from the diet
D) gastrointestinal microflora
C) from the diet
How do antioxidant vitamins stabilize free radicals?
A) donate electrons or hydrogens
B) enzymatic destruction
C) phagocytosis
D) break down and convert them to less damaging molecules
A) donate electrons or hydrogens
Which of the following diseases has been linked to free radical damage?
A) cancer
B) celiac disease
C) anemia
D) gallstones
A) cancer
The most powerful and abundant form of vitamin E is:
A) alpha-tocopherol.
B) alpha-tocotrienol.
C) gamma-tocopherol.
D) delta-tocopherol.
A) alpha-tocopherol.
Which water-soluble vitamin can regenerate vitamin E after it has been oxidized?
A) vitamin D
B) vitamin B12
C) vitamin C
D) folate
C) vitamin C
About 90% of vitamin E is stored in:
A) adipose tissue.
B) the liver.
C) cell membranes.
D) the skin.
A) adipose tissue.
Which of the following is a function of vitamin E?
A) protecting PUFA (polyunsaturated fatty acids) in cell membranes from oxidation
B) regenerating vitamin C by donating an electron
C) improving the absorption of vitamin C if dietary intake is low
D) increasing bone density
A) protecting PUFA (polyunsaturated fatty acids) in cell membranes from oxidation
Which of the following foods are the richest sources of vitamin E?
A) milk and dairy products
B) fruits and vegetables
C) meat, fish, and poultry
D) vegetable oils
D) vegetable oils
Which of the following foods will have the least amount of viable vitamin E?
A) chicken fried in vegetable oil
B) bread dipped in sunflower oil
C) peanuts, dry roasted
D) salad with canola oil and vinegar
A) chicken fried in vegetable oil
Taking vitamin E supplements along with ___ can cause uncontrollable bleeding.
A) antidepressants
B) anticoagulants
C) cholesterol-lowering medications
D) oral contraceptives
B) anticoagulants
Vitamin E is added to many oil-based skin care products because:
A) it prevents oxidation in these products.
B) it has an additive affect on the function of the products.
C) it is an inactive filler.
D) it improves the smell and texture of the products.
A) it prevents oxidation in these products.
Vitamin E is critical for:
A) normal fetal and early childhood development.
B) athletic performance.
C) postmenopausal women.
D) adolescent growth.
A) normal fetal and early childhood development.
Diseases that cause the malabsorption of fat can result in a deficiency of:
A) copper.
B) vitamin E.
C) vitamin C.
D) selenium.
B) vitamin E.
Which of the following nutrients requires the most frequent consumption to ensure adequate body stores?
A) vitamin A
B) vitamin E
C) vitamin C
D) beta-carotene
C) vitamin C
The deficiency disease associated with vitamin C is:
A) scurvy.
B) erythrocyte hemolysis.
C) night blindness.
D) Keshan disease.
A) scurvy.
Vitamin C assists in the formation of the structural protein called ___.
A) elastin
B) collagen
C) titan
D) ostiod
B) collagen
The doctor has recently told Julie that she is anemic. Julie should consume ___ with her iron supplement to increase its absorption.
A) a tablespoon of castor oil
B) a glass of milk
C) a glass of orange juice
D) scrambled eggs
C) a glass of orange juice
Which of the following increases the RDA for vitamin C?
A) smoking cigarettes
B) drinking alcohol
C) following a vegan diet
D) taking vitamin C supplements
A) smoking cigarettes
Which of the following are rich sources of vitamin C?
A) milk and cheese
B) seafood
C) wheat and oats
D) green and red peppers
D) green and red peppers
Which of the following is the best source of vitamin C?
A) citrus fruit
B) pork chops
C) hazel nuts
D) butter
A) citrus fruit
Absorption of which mineral is enhanced by vitamin C?
A) iron
B) copper
C) selenium
D) calcium
A) iron
Which of the following symptoms is associated with consuming a megadose of vitamin C?
A) night blindness
B) scurvy
C) nausea and diarrhea
D) erythrocyte hemolysis
C) nausea and diarrhea
Which of the following is considered an essential nutrient?
A) glycerol
B) beta-carotene
C) homocysteine
D) vitamin E
D) vitamin E
Which of the following carotenoids can be converted to retinol in the body?
A) lutein
B) beta-carotene
C) lycopene
D) retinol
B) beta-carotene
Which of the following is a function of carotenoids?
A) produces thyroxine
B) activate the glutathione peroxidase enzyme system
C) supports the immune system
D) increases cellular metabolic rate
C) supports the immune system
Provitamins are:
A) vitamins with overwhelmingly positive effects when taken in the correct amounts.
B) inactive forms of vitamins that the body cannot use until they’re converted to their active form.
C) prooxidents that have taken a new form.
D) vitamins with antioxidant properties.
B) inactive forms of vitamins that the body cannot use until they’re converted to their active form.
Compared to vitamin E, beta-carotene is:
A) a relatively weak antioxidant.
B) more easily absorbed and utilized by the body.
C) a better choice for people with GI tract problems.
D) a stronger antioxidant.
A) a relatively weak antioxidant.
Which of the following contains the greatest amount of bioavailable beta-carotene?
A) 1 cup raw carrots
B) 1 cup frozen carrots
C) 1 cup lightly cooked carrots
D) 1 cup thoroughly cooked carrots
C) 1 cup lightly cooked carrots
Foods that use beta-carotene as a natural coloring agent:
A) generally must be processed heavily.
B) are not significant sources of beta-carotene.
C) are largely foods with a high fat content.
D) also acquire a distinctive taste.
B) are not significant sources of beta-carotene.
The retinoid that has the most significant physiological role in the human body is:
A) retinol.
B) retinoic acid.
C) retinal.
D) beta-carotene.
A) retinol.
Where is beta-carotene converted to retinol?
A) in the stomach
B) in the liver
C) in the small intestine
D) in the large intestine
C) in the small intestine
Which of the following foods would be the BEST dietary source of pre-formed vitamin A?
A) carrots
B) egg
C) cantaloupe
D) rice
B) egg
Vitamin A affects our vision in two ways. it enables us to react to changes in brightness, and:
A) it enables us to see different colors.
B) it enables us to focus on distant objects.
C) it supports eye functioning later in life.
D) it supports the development of eye functioning in fetuses.
A) it enables us to see different colors.
When levels of vitamin A are deficient, people suffer from a condition known as:
A) astigmatism.
B) near-sightedness
C) night blindness.
D) partial blindness.
C) night blindness.
Which of the following hormones requires selenium for its synthesis?
A) estrogen
B) insulin
C) cortisol
D) thyroxine
D) thyroxine
Where in the body is selenium contained?
A) in the liver
B) in adipose tissue
C) in the lymph system
D) in amino acids
D) in amino acids