Deck 10: The Water-Soluble Vitamins: B Vitamins and Vitamin C

Question 1

What is the primary excretory route for the water-soluble vitamins?

A)Bile
B)Kidney
C)Intestine
D)Perspiration

Answer 1

B

Question 2

Which of the following functions has a requirement for thiamin?

A)Blood coagulation
B)Formation of red blood cells
C)Energy release from energy-yielding nutrients
D)Formation of epithelial cell mucopolysaccharides

Answer 2

C

Question 3

Which of the following is a property of thiamin nutrition?

A)Participates in activation of prothrombin
B)Poor sources include seafood and cheeses
C)Significant amounts are found in leafy vegetables
D)Deficiency results in cheilosis and marked dermatitis

Answer 3

B

Question 4

All of the following are characteristic of thiamin nutrition except

A)severe deficiency may lead to edema.
B)severe deficiency may occur without edema.
C)recommended intakes are stated in "equivalents."
D)recommended intakes are based primarily on participation in enzyme activity.

Question 5

When thiamin is consumed in excess of needs, how does the body treat the excess?

A)Not absorbed
B)Excreted primarily in the urine
C)Excreted primarily in the feces
D)Stored in liver, bone, and adipose tissue

Question 6

Which of the following vitamins would be removed in the production of skim milk?

A)Thiamin
B)Vitamin A
C)Riboflavin
D)Vitamin B₁₂

Question 7

Which of the following diets is most likely to lead to beriberi?

A)High intakes of white rice
B)Low intakes of whole grains
C)High intakes of unrefined rice
D)Low intakes of enriched grains

Question 8

What is meant by the bioavailability of a vitamin in food?

A)The total amount available from plant and animal food
B)The amount absorbed and subsequently used by the body
C)The amount that escapes destruction from food processing
D)The number of different chemical forms of the same vitamin

Question 9

Cooking a food in liberal amounts of water is least likely to affect the vitamin content of

A)folate.
B)thiamin.
C)vitamin A.
D)riboflavin.

Question 10

Which of the following is a characteristic of thiamin nutrition?

A)The coenzyme contains pyrosulfate
B)It is required for regeneration of folate
C)It is required for regeneration of niacin
D)It is an integral part of the nerve cell membrane

Question 11

Which of the following provides the most thiamin per serving size?

A)Ham
B)Squash
C)Whole milk
D)Whole-grain breads

Question 12

All of the following are general characteristics of the fat-soluble vitamins except

A)excesses are eliminated from the kidneys.
B)absorption is via the lymphatic circulation.
C)several of them require protein carriers for transport.
D)they can be stored in relatively large amounts in certain body tissues.

Question 13

General characteristics of the water-soluble vitamins include all of the following except

A)they must be consumed daily.
B)toxic levels in the body are rarely found.
C)they are absorbed directly into the blood.
D)excesses are eliminated from the kidneys.

Question 14

Which of the following is the coenzyme form of thiamin?

A)Thiaminacide
B)Thiamin pyrophosphate
C)Thiamin adenine dinucleotide
D)Thiamin flavin mononucleotide

Question 15

What is the primary chemical reaction in which thiamin participates as a coenzyme?

A)Transfers amine groups in the synthesis of amino acids
B)Transfers hydrogen atoms in the synthesis of erythrocytes
C)Assists in addition of methyl groups to compounds involved in energy metabolism
D)Assists in removal of one-carbon units from compounds involved in energy metabolism

Question 16

The Wernicke-Korsakoff syndrome may be treated with supplements of

A)folacin.
B)thiamin.
C)vitamin C.
D)vitamin B₁₂.

Question 17

What is a precursor?

A)A conditionally essential vitamin
B)A sign or symptom of a vitamin deficiency disorder
C)A substance that is used to synthesize another compound
D)A substance that is recycled through the liver and intestines

Question 18

Approximately what percentage of alcoholics exhibit thiamin deficiency?

A)20
B)40
C)60
D)80

Question 19

Which of the following is a feature of vitamins?

A)Many serve in the role of enzyme inhibitors
B)Structurally, many are found linked together
C)Several may be oxidized to yield 4 kcalories per gram
D)The quantities present in foods are measured in micrograms or milligrams

Question 20

Beriberi results from a deficiency of

A)niacin.
B)thiamin.
C)vitamin C.
D)vitamin B₁₂.

Question 21

Of the following, which is the richest food source of thiamin?

A)Lettuce
B)Soy milk
C)Cow milk
D)Refined rice

Question 22

A low-protein diet in which corn is a principal food has been found to cause a deficiency of what vitamin?

A)Niacin
B)Thiamin
C)Vitamin C
D)Vitamin B₁₂

Question 23

Which of the following contains the highest concentration of thiamin in muscle tissue?

A)Pig
B)Fish
C)Steer
D)Chicken

Question 24

Which of the following is a property of niacin in nutrition?

A)It is susceptible to destruction in foods exposed to light
B)It participates primarily in reactions involving amino acids
C)It is soluble in both water and lipids depending upon its chemical form
D)It can be synthesized in the body from the essential amino acid tryptophan

Question 25

A deficiency of what vitamin produces a characteristic cracking and redness at the corners of the mouth?

A)Biotin
B)Niacin
C)Riboflavin
D)Ascorbic acid

Question 26

Which of the following is indicative of a dietary deficiency of riboflavin?

A)Beriberi
B)Diarrhea
C)Keratomalacia
D)Inflamed mouth membranes

Question 27

The vitamin deficiency disease pellagra means

A)"rough skin."
B)"paralyzed limbs."
C)"demented behavior."
D)"flattened erythrocytes."

Question 28

How does the method of cooking affect thiamin stability?

A)Microwaving the food conserves much of the thiamin
B)Prolonged heating of the food has little, if any, effect on the thiamin
C)Boiling the food tends to conserve thiamin by forming a stable, hydrated complex
D)Steaming the food can lead to substantial thiamin loss due to the high heat needed to form the steam

Question 29

Which of the following nutrients functions to prevent the appearance of a bilateral, symmetrical dermatitis, primarily on areas exposed to the sun?

A)Niacin
B)Choline
C)Inositol
D)Riboflavin

Question 30

Which of the following vitamins is involved substantially in energy transformation reactions?

A)Biotin
B)Cobalamin
C)Riboflavin
D)Pyridoxine

Question 31

Which of the following is a property of riboflavin in nutrition?

A)Stability to heat is good
B)Deficiency leads to beriberi
C)Requirements are proportional to body weight
D)Significant amounts are found in citrus products

Question 32

Riboflavin needs are more difficult to meet when the diet is low in

A)meats.
B)grains.
C)vegetables.
D)dairy foods.

Question 33

Which of the following food groups ordinarily contains the highest amount of riboflavin when expressed per kcalorie?

A)Dairy
B)Meats
C)Fruits
D)Vegetables

Question 34

Riboflavin in its coenzyme form functions in the transfer of

A)methyl groups.
B)1-carbon units.
C)2-carbon units.
D)hydrogen atoms.

Question 35

The signs and symptoms of riboflavin deficiency are known collectively as

A)pellagra.
B)antiflavonosis.
C)ariboflavinosis.
D)flavin adenine dinucleosis.

Question 36

Which of the following properties is shared by niacin and riboflavin coenzymes?

A)Unstable to irradiation
B)Unstable to metal cooking utensils
C)Acceptance and transfer of hydrogen atoms
D)Acceptance and transfer of carboxyl groups

Question 37

Riboflavin is most easily destroyed when exposed to

A)heat.
B)acid.
C)alkali.
D)ultraviolet light.

Question 38

What is ariboflavonosis?

A)The vitamin B₂ deficiency disease
B)Food sources devoid of vitamin B₂
C)Ultraviolet destruction of vitamin B₂
D)Excessive heat destruction of vitamin B₂

Question 39

While researching your southern family history, you find that your grandmother had a sister who died fairly young.The symptoms leading up to her death included diarrhea, dermatitis, and dementia.Because the family led a poor, corn-farming existence, you suspect this relative died of

A)scurvy.
B)cancer.
C)pellagra.
D)beriberi.

Question 40

When the diet contains an adequate amount of protein, what amino acid can be used by the body to synthesize niacin?

A)Lysine
B)Valine
C)Tryptophan
D)Phenylalanine

Question 41

Your brother Bob is a competitive body builder.His trainer suggested that he consume 4 egg white omelets per day.Bob remembers a warning about a possible vitamin deficiency from consuming too many egg whites and asks if he should follow the prescribed diet.Your reply to Bob is that he should not

A)be concerned as long as he consumes both the yolk and whites of the eggs.
B)follow the diet, since the avidin in the egg whites could bind to niacin and prevent its absorption.
C)follow the diet, since the avidin in the egg whites could bind to biotin and prevent its absorption.
D)be concerned, because, when the eggs are cooked, the avidin protein is denatured, and thus does not pose a problem for deficiency disease.

Question 42

Biotin can be synthesized by

A)avidin.
B)the skin.
C)the liver.
D)intestinal bacteria.

Question 43

Which of the following overt side effect(s) is likely to appear after a person ingests a high quantity of nicotinic acid?

A)Constipation
B)Mental confusion
C)Painful, tingling, itching sensation
D)Hair loss, bloating, and photophobia

Question 44

Large doses of nicotinic acid are known to result in all of the following except

A)dilation of capillaries.
B)increased HDL cholesterol.
C)lowering of LDL cholesterol.
D)disappearance of learning disorders in children.

Question 45

What is the AI for pantothenic acid for adults?

A)1 mg
B)3 mg
C)5 mg
D)8 mg

Question 46

Which of the following substances is found in corn and contributes to the development of pellagra?

A)Avidin
B)Leucine
C)Phytates
D)Phenylalanine

Question 47

What term identifies the characteristic tingling sensations and reddening of the skin after ingesting a pharmacologic dose of nicotinic acid?

A)Niacin flush
B)NAD dermatitis
C)Niacin erythrema
D)Bilateral symmetrical dermatitis

Question 48

What is the adult Adequate Intake for biotin?

A)3 µg
B)30 µg
C)3 mg
D)30 mg

Question 49

Features of biotin in nutrition include all of the following except

A)it functions in the breakdown of amino acids and fatty acids.
B)it functions as a carrier of carbon dioxide in energy metabolism.
C)a deficiency can be induced by ingesting large quantities of raw egg whites.
D)a deficiency can be induced by ingesting large amounts of thiamin and folic acid, which interfere with its absorption.

Question 50

When taken in large doses, which of the following vitamins is associated with liver injury and peptic ulcers?

A)Niacin
B)Thiamin
C)Vitamin B₆
D)Vitamin B₁₂

Question 51

Among the following compounds that serve as coenzymes in metabolism, which is considered a vitamin for human beings?

A)Biotin
B)Inositol
C)Lipoic acid
D)Orotic acid

Question 52

Which of the following vitamins is known to sustain substantial losses during processing of food?

A)Biotin
B)Niacin
C)Vitamin B₁₂
D)Pantothenic acid

Question 53

What vitamin forms a part of coenzyme A?

A)Biotin
B)Folate
C)Riboflavin
D)Pantothenic acid

Question 54

Which of the following vitamins is stored primarily in muscle tissue?

A)Biotin
B)Folate
C)Vitamin B₆
D)Pantothenic acid

Question 55

Which of the following vitamins is synthesized by intestinal bacteria?

A)Folate
B)Biotin
C)Cyanocobalamin
D)Pantothenic acid

Question 56

Your friend Jane just returned from the doctor who diagnosed her with a specific vitamin B toxicity.However, she doesn't recall the name of the vitamin.Which of the following is the only possible culprit associated with toxicity symptoms?

A)Niacin
B)Biotin
C)Riboflavin
D)Vitamin B₁₂

Question 57

Which of the following is a feature of niacin nutrition?

A)Low doses may lead to kidney stones
B)High doses may lower blood cholesterol
C)Low doses may lead to heartburn and low blood pressure
D)High doses may elevate red blood cell count in mildly anemic individuals

Question 58

A protein that binds with biotin (thus inhibiting absorption) is found in which food?

A)Aged cheese
B)Raw egg whites
C)Whole wheat bread
D)Unhomogenized milk

Question 59

Forms of vitamin B₆ include all of the following except

A)pyridoxal.
B)pyridoxine.
C)pyrimidine.
D)pyridoxamine.

Question 60

Which of the following foods contains a protein that decreases bioavailability of biotin?

A)Aged wine
B)Aged cheese
C)Raw egg whites
D)Raw cauliflower

Question 61

The percent bioavailability of a folate supplement taken on an empty stomach is

A)5.
B)25.
C)50.
D)100.

Question 62

A common drug for the treatment of tuberculosis is known to markedly interfere in the metabolism of vitamin

A)B₆.
B)B₁₂.
C)C.
D)D.

Question 63

What is the Tolerable Upper Intake Level for vitamin B₆?

A)100 mg
B)500 mg
C)1000 mg
D)10,000 mg

Question 64

Irreversible nerve damage has been reported in people taking large doses of

A)vitamin B₁.
B)vitamin B₂.
C)vitamin B₆.
D)vitamin B₁₂.

Question 65

Which of the following vitamins undergoes significant enterohepatic circulation?

A)Folate
B)Niacin
C)Thiamin
D)Pyridoxine

Question 66

In what major way does alcohol intake affect vitamin B₆ metabolism?

A)It reduces acetaldehyde formation
B)It increases fecal excretion of the vitamin
C)It dislodges the PLP coenzyme from its enzyme
D)It interferes with synthesis of the PLP coenzyme

Question 67

What vitamin is involved intensively in amino acid metabolism?

A)Biotin
B)Vitamin A
C)Vitamin B₆
D)Riboflavin

Question 68

Research has shown that the risk for neural tube defects is lowered by taking supplements of

A)niacin.
B)folate.
C)vitamin C.
D)vitamin B₁₂.

Question 69

How many dietary folate equivalents are provided by 100 µg of a folate supplement?

A)50
B)70
C)133
D)170

Question 70

A person with a disorder that limits absorption of bile is at increased risk for deficiency of

A)folate.
B)niacin.
C)riboflavin.
D)ascorbic acid.

Question 71

What is the most likely explanation for the impaired functioning of the GI tract resulting from folate deficiency?

A)Since folate is required for bile synthesis, folate deficiency results in insufficient bile production, thereby promoting fat malabsorption and diarrhea
B)Since folate functions, in large part, in the process of cell renewal, a deficiency slows mucosal cell replacement, thereby resulting in decreased GI functioning
C)The anemia of folate deficiency results in decreased oxygen supply to body tissues, with the intestines being particularly affected because of their high metabolic activity
D)Since folate functions, in part, in the synthesis of pancreatic digestive enzymes, a deficiency leads to decreased enzymatic capacity in the intestines, thereby resulting in malabsorption

Question 72

All of the following are features of vitamin B₆ metabolism except

A)a deficiency or toxicity leads to depression.
B)its destruction and excretion are promoted by alcohol intake.
C)it functions primarily as the coenzyme pyridoxal phosphate.
D)it enhances physical performance when supplied at a level of l mg/g of dietary protein.

Question 73

Which of the following is not a feature of folate nutrition?

A)Most food folate is bound to a string of amino acids
B)Folate is actively secreted back into the GI tract with bile
C)Food folate must be hydrolyzed by intestinal cell enzymes prior to absorption
D)Folate must be methylated by homocysteine prior to crossing the brush border membrane

Question 74

Approximately what percentage of dietary folate is bioavailable?

A)10
B)25
C)50
D)80

Question 75

Which of the following vitamins is usually found in a form that is bound to one or more glutamic acid molecules in food?

A)Folate
B)Thiamin
C)Vitamin B₆
D)Ascorbic acid

Question 76

Which of the following statements reflects our knowledge of water-soluble vitamin toxicity?

A)Toxicity symptoms for vitamin B₆ can be severe and irreversible
B)Toxicity symptoms for vitamin C include constipation and hyperactivity
C)Toxicities of the B vitamins occur almost as often from foods as from supplements
D)Toxicity of niacin has been reported in body builders taking large amounts of amino acid supplements

Question 77

What fraction of women capable of becoming pregnant ingest the RDA for folate?

A)¼
B)¹/₃
C)½
D)²/₃

Question 78

Which of the following is not a characteristic of vitamin B₆ in nutrition?

A)It is stored in muscle tissue
B)It is required in amounts proportional to energy expenditure
C)It can lead to irreversible nerve damage when taken in large doses
D)It functions, in part, in the synthesis of glycine and glutamic acid

Question 79

Pteroylglutamic acid is known as

A)folate.
B)choline.
C)inositol.
D)pyridoxamine.

Question 80

The chief symptoms of early vitamin B₆ deficiency include

A)confusion and depression.
B)muscle cramps and stiffness.
C)profound fatigue and anemia.
D)hyperactivity and shortness of breath.