Deck 11: The Fat-Soluble Vitamins: A, D, E, and K

Question 1

Why does vitamin A status depend on the person's protein status? ​

A)Adequate protein intake is a marker for liberal intake of the vitamin.
B)Dietary protein ensures synthesis of the vitamin's GI tract transporter.
C)Adequate protein intake reduces the risk for infection from bacteria that degrade the vitamin.
D)Transport of the vitamin within the body requires sufficient protein to synthesize retinol-binding protein.

Answer 1

D

Question 2

How many different forms of vitamin A are active in the body?

A)1 ​
B)2
C)3
D)5

Answer 2

C

Question 3

What is the major carrier of the fat-soluble vitamins from the intestinal epithelial cell to the circulation?

A)​a lbumin
B)​c holesterol
C)​c hylomicrons
D)​l ipid-soluble binding proteins

Answer 3

C

Question 4

What do beta-carotene and vitamin E have in common? ​

A)Both act as antioxidants.
B)Both are found in animal fats.
C)Neither is involved in free radical control.
D)Neither is involved in synthesis of retinal.

Question 5

What do retinal and unsaturated fatty acids have in common?

A)Neither is found in animal fats.
B)Neither is transported by chylomicrons.
C)They may exist in the cis or trans form.
D)They are both needed to prevent erythrocyte hemolysis.

Question 6

The first detectable sign of vitamin A deficiency is usually ____. ​

A)xerosis
B)xerophthalmia
C)night blindness
D)corneal keratinization

Question 7

Which statement describes an association between vitamin A and vision? ​

A)Retinoic acid is the form required for synthesis of retinoblasts.
B)Light causes retinal to shift from a cis to a trans configuration.
C)Retinol is the form bound to beta-carotene in the corneal membrane.
D)Pigment molecules in the retina are composed of a molecule of vitamin A bound to an omega-3 fatty acid.

Question 8

What part of the body is affected most by keratomalacia? ​

A)bone
B)liver
C)cornea
D)immune cells

Question 9

What is the most likely side effect for a person who regularly consumes large quantities of carrots or carrot juice?

A)bone pain
B)dermatitis
C)skin yellowing
D)vitamin A toxicity

Question 10

The effects of vitamin A deficiency are most severe in what population group? ​

A)adults
B)elderly
C)newborns
D)adolescents

Question 11

What is the name of the vitamin A compound that is active in the visual response?

A)opsin
B)keratin
C)retinal
D)carotene

Question 12

What are the known effects of raising animals on diets containing retinoic acid as the only source of vitamin A? ​

A)Growth is stunted.
B)Blindness develops.
C)Retinal synthesis is stimulated.
D)Retinol synthesis is stimulated.

Question 13

Which statement describes a feature of vitamin A nutrition? ​

A)Deficiency is common in United States.
B)Toxicity occurs from excess intakes of preformed vitamin A as well as beta-carotene.
C)Supplements are recommended for certain groups of infants and children infected with the measles in the United States.
D)In poor countries, supplements prevent and cure night blindness but offer little protection against malaria and lung disease.

Question 14

What form of vitamin A supports reproduction but not growth?

A)retinal
B)retinol
C)retinoic acid
D)retinyl esters

Question 15

What is a property of the fat-soluble vitamins? ​

A)Most of them are synthesized by intestinal bacteria.
B)Intestinal transport occurs by way of the portal circulation.
C)Deficiency symptoms may take years to develop on a poor diet.
D)Toxicity risk is higher for vitamins E and K than for other fat-soluble vitamins.

Question 16

The preferred unit of expression of vitamin A is the ____. ​

A)milligram
B)global unit
C)international unit
D)retinol activity equivalent

Question 17

How many micrograms of dietary beta-carotene are equivalent to 1 retinol activity equivalent? ​

A)​2
B)​4
C)​8
D)​12

Question 18

If a normal, healthy adult were to begin consuming a vitamin A-poor diet, approximately how much time would pass before the first deficiency symptoms would appear? ​

A)2 weeks
B)1 to 2 months
C)6 months
D)1 to 2 years

Question 19

Which food substance can be converted into vitamin A in the body? ​

A)​t ryptophan
B)chlorophyll
C)​x anthophyll
D)​b eta-carotene

Question 20

Which statement describes the primary function of vitamin A in bone health? ​

A)It stimulates uptake of calcium from the intestines.
B)It promotes synthesis of specific bone proteins involved in the mineralization process.
C)It assists enzymes that degrade certain regions of the bone, thereby allowing remodeling to occur.
D)It inhibits oxidation of bone mucopolysaccharides, thereby preserving bone crystal integrity and promoting growth.

Question 21

In what system would the effects of a vitamin D deficiency be most readily observed? ​

A)nervous
B)skeletal
C)muscular
D)circulatory

Question 22

The plant version of vitamin D is known as ____. ​

A)ergocalciferol
B)foliocalciferol
C)cholecalciferol
D)phyllocalciferol

Question 23

What is a characteristic of vitamin A in foods? ​

A)Fast foods are generally considered good sources of vitamin A.
B)A regular intake of chicken liver is known to induce toxicity in children.
C)Xanthophylls in certain vegetables can be converted to active vitamin A in the liver.
D)Chlorophyll in vegetables can be converted to active vitamin A in the intestinal cells.

Question 24

What is/are the main function(s)of vitamin D? ​

A)​It  promotes secretion of calcitonin.
B)​It  promotes synthesis of 7-dehydrocholesterol.
C)​It  promotes synthesis of carotenoids and controls absorption of fat-soluble vitamins.
D)​It  promotes calcium and phosphorus absorption and promotes calcium mobilization from bone.

Question 25

What is a feature of vitamin D synthesis? ​

A)Tanning lamps and tanning booths do not stimulate vitamin D synthesis.
B)Sunscreens with sunburn protection factors of 2 and above prevent synthesis of vitamin D.
C)The ultraviolet rays of the sun are able to easily pierce heavy clouds and smog to promote vitamin D synthesis.
D)Dark-skinned people require longer sunlight exposure than light-skinned people to synthesize equivalent amounts of vitamin D.

Question 26

What population group is at highest risk for osteomalacia? ​

A)infants
B)elderly men
C)adult women
D)children ages 2-12 years

Question 27

Which food is a very good source of vitamin A? ​

A)corn
B)pumpkin pie
C)baked potato
D)whole-grain bread

Question 28

Which compound is known to function as a hormone? ​

A)vitamin D
B)vitamin K
C)phylloquinone
D)alpha-tocopherol

Question 29

What can the body use to synthesize vitamin D? ​

A)bone
B)carotene
C)tryptophan
D)exposure to sunlight

Question 30

Where is calbindin primarily found in the body? ​

A)liver
B)kidneys
C)intestine
D)esophagus

Question 31

What is a feature of vitamin A in foods? ​

A)Carotenoid absorption is inhibited by foods rich in chlorophyll.
B)Margarine made from corn oil is a poor source of vitamin A.
C)Most carotenoids can be converted in the body to active vitamin A.
D)Chlorophyll in dark green leafy vegetables masks the presence of beta-carotene.

Question 32

Which conditions or diseases are known to be caused by a deficiency of the same nutrient? ​

A)osteomalacia and rickets
B)xerophthalmia and breath pentane release
C)kwashiorkor and fibrocystic breast disease
D)hemolytic anemia and large-cell type anemia

Question 33

The animal version of vitamin D is known as ____. ​

A)ergocalciferol
B)foliocalciferol
C)cholecalciferol
D)phyllocalciferol

Question 34

What is the most reliable source of vitamin D in the diet? ​

A)meat
B)fortified milk
C)fruits and vegetables
D)enriched breads and cereals

Question 35

Which symptom would indicate a vitamin D deficiency? ​

A)bowed legs
B)rupture of red blood cells
C)frequent respiratory infections
D)abnormally high blood calcium level

Question 36

Absorption efficiency of vitamin D supplements is markedly improved when they are taken ____. ​

A)with a large meal
B)with a small meal
C)with orange juice
D)on an empty stomach

Question 37

Your sister Ellen has just joined the Peace Corps and will be working on ways to improve the nutritional status of children in Indonesia. Once there, she saw that many of the children and some adults suffer from night blindness. Which food should she recommend be incorporated into the Indonesian diet to help prevent future generations from developing this condition? ​

A)sweet potato
B)orange juice
C)peanut butter
D)powdered skim milk

Question 38

What is a feature of vitamin D?

A)The bioavailability of vitamin D from soy milk is low.
B)Lifeguards on southern beaches have increased risk for vitamin D toxicity.
C)Only about one-half of the world's population relies on sunlight to maintain adequate vitamin D nutrition.
D)Prolonged exposure to sunlight degrades the vitamin D precursor in skin, thus preventing vitamin D toxicity.

Question 39

What is a naturally occurring food source of vitamin D? ​

A)egg yolks
B)red meats
C)tomato juice
D)whole-wheat bread

Question 40

Which individual would be most likely to develop a vitamin A toxicity? ​

A)adolescent women
B)overweight adults
C)those taking vitamin A supplements
D)those consuming more than 100 g of carrots daily

Question 41

Increasing the amount of polyunsaturated fats in the diet increases the need for vitamin ____. ​

A)​A
B)​E
C)​K
D)​D

Question 42

What is a feature of vitamin K? ​

A)Deficiencies lead to intravascular clotting.
B)Major dietary sources are whole grains and legumes.
C)No adverse effects have been reported with high intakes.
D)Primary deficiencies are more common than secondary deficiencies.

Question 43

Which molecule requires vitamin K for its synthesis? ​

A)albumin
B)pyruvate
C)prothrombin
D)mucopolysaccharides

Question 44

Which properties do vitamins D and K share? ​

A)Both are synthesized in the body.
B)Both are required for normal vision.
C)Neither has an effect on bone metabolism.
D)Neither has an effect on erythrocyte function.

Question 45

Which type of food is a major source of vitamin E in the diet? ​

A)meats
B)citrus fruits
C)vegetable oils
D)milk and dairy products

Question 46

What is a feature of vitamin K? ​

A)A deficiency increases the risk for hemophilia.
B)A deficiency leads to keratinization of the cornea.
C)Bacteria in the intestines synthesize bioavailable vitamin K.
D)There are multiple forms in the diet, of which menadione is the naturally occurring form.

Question 47

What is a property of the tocopherols? ​

A)​They are  easily destroyed by air and oxygen.
B)​They  act as precursors for the menaquinones.
C)They ​ can all be converted to the active alpha-tocopherol.
D)​They are  fairly stable when exposed to heat.

Question 48

What form of tocopherol shows vitamin E activity in the human body?

A)alpha
B)beta
C)gamma
D)delta

Question 49

What would most readily induce a vitamin K deficiency? ​

A)achlorhydria
B)antibiotic therapy
C)presence of oxalic acid in food
D)insufficient intake of green leafy vegetables

Question 50

Which condition may improve with vitamin E therapy? ​

A)diabetes
B)pernicious anemia
C)muscular dystrophy
D)intermittent claudication

Question 51

What is a feature of vitamin E? ​

A)It functions as a hormone-like substance.
B)Toxicity symptoms include bone abnormalities.
C)Deficiencies occur from inability to absorb dietary lipids.
D)Important food sources include enriched breads and pasta.

Question 52

What is a feature of osteocalcin? ​

A)It activates lysosomes involved in remodeling bone.
B)It binds calcium in the GI tract to enhance absorption.
C)It requires vitamin K to bind to bone-forming minerals.
D)It works synergistically with the kidneys to reduce urinary calcium excretion.

Question 53

Why are primary vitamin E deficiencies rarely observed in human beings? ​

A)The vitamin is not essential.
B)The vitamin is widespread in foods.
C)Most people take vitamin E supplements.
D)The vitamin can be synthesized by the body.

Question 54

What population group has the highest risk for vitamin K deficiency? ​

A)adults
B)elderly
C)newborns
D)teenagers

Question 55

What is a characteristic of vitamin K nutrition? ​

A)Deficiency may lead to hemophilia.
B)Toxicity may increase risk for hemophilia.
C)Absorption is inhibited when bile production diminishes.
D)Supplements are highly effective against osteoporosis.

Question 56

What feature is shared by vitamins E and K? ​

A)Deficiencies of either lead to anemia.
B)Both have strong antioxidant properties.
C)Neither is involved in bone development.
D)Supplements of either may interfere with anticlotting medications.

Question 57

The major function of vitamin E is to inhibit the destruction of ____. ​

A)lysosomes
B)free radicals
C)mucopolysaccharides
D)polyunsaturated fatty acids

Question 58

Which vitamin is synthesized by intestinal bacteria? ​

A)​A
B)​E
C)​K
D)​D

Question 59

Which vitamin prevents the oxidation of low-density lipoproteins? ​

A)​A
B)​E
C)​K
D)​D

Question 60

Which vitamin is least associated with the process of bone remodeling?

A)​A
B)​K
C)​E
D)​D

Question 61

What is a feature of antioxidants and health? ​

A)Dietary antioxidants protect against free radical formation but not against DNA damage.
B)Beta-carotene supplements have actually been shown to increase the risk of lung cancer in smokers.
C)Diet surveys show that most of the U.S. population consumes recommended amounts of antioxidant nutrients.
D)People who eat foods rich in vitamin E still have the same level of atherosclerotic plaques as consumers who don't.

Question 63

What is a characteristic of free radicals? ​

A)They are destroyed by cigarette smoking.
B)They arise from normal metabolic reactions.
C)They typically stop chain reactions associated with the production of peroxides.
D)They are known to accumulate even in the presence of abundant antioxidant nutrients.

Question 73

What is a characteristic of both vitamin C and vitamin E? ​

A)Both protect against LDL oxidation.
B)Neither reduces arterial inflammation.
C)Neither participates in regulating blood clotting.
D)Both act as prooxidants at physiological intakes.

Question 74

What is a free radical? ​

A)an antioxidant substance that prevents accumulation of cell-damaging oxides
B)a substance in food that interacts with nutrients to decrease their utilization
C)a nutrient in excess of body needs that the body is free to degrade with no consequence
D)a molecule that is unstable and highly reactive because it contains unpaired electrons

Question 78

Which molecule is a major form of vitamin K in foods? ​

A)ergodione
B)ergoquinone
C)tocopherone
D)phylloquinone

Question 79

Substances that promote oxidation are usually termed ____. ​

A)prooxidants
B)antioxidants
C)free radical generators
D)reactive electron oxidants

Question 80

What is the best source of dietary vitamin K?

A)spinach
B)raspberries
C)whole wheat bread
D)baked potato