Class Quizzes Flashcards Preview

NUTR 560C Vitamins and Minerals > Class Quizzes > Flashcards

Flashcards in Class Quizzes Deck (127)
Loading flashcards...
1
Q

The term “vitamers” refers to:
A. all of the vitamins that begin with the same letter
B. vitamins that are not amines
C. minerals that may behave like vitamins
D. closely-related compounds that have similar vitamin activity

A

D. closely-related compounds that have similar vitamin activity

2
Q

When water-soluble vitamins are consumed in excess of body needs, generally the excess is:
A. stored in liver, bone, and adipose tissue.
B. not absorbed.
C. excreted in the feces.
D. excreted in the urine.

A

D. excreted in the urine.

3
Q
A major function of B vitamins is to serve as:
A. electrolytes. 
B. a source of energy. 
C. a part of a coenzyme. 
D. antibodies.
A

C. a part of a coenzyme.

4
Q

Match the Dietary Reference Intake item with it’s appropriate definition
RDA
EAR
UL

A

RDA - Meets requirements of 97% healthy people in specified age or gender group
EAR - thought to meet the needs of 50% of people in specified age or gender group
UL- highest level unlikely to cause adverse effects in almost all people

5
Q

Food sources of B-vitamins that are in coenzyme forms, are phosphorylated, or are bound to proteins require digestion in order to release the free vitamin for absorption from the intestine.
A. True
B. False

A

A. True

6
Q

Match the vitamin with the correct enzyme or coenzyme function.

Pantothenic acid
Thiamin
Niacin
Riboflavin

A

Pantothenate - Acyl carrier protein
Thiamin - TDP
Niacin - NADP/NADPH
Riboflavin - FMN/FMNH2

7
Q
A thiamin deficiency disorder usually associated with alcoholism is known as:
A. Wernicke-Korsakoff Syndrome 
B. Maple Syrup Urine Disease 
C. Cirrhosis of the liver 
D. Beriberi
A

A. Wernicke-Korsakoff Syndrome

8
Q
The essential roles of thiamin in the body include (Indicate all of the correct answers):
A. Synthesis of pentoses and NADPH 
B. Synthesis of coenzyme A 
C. Energy transformation 
D. Membrane and nerve conduction
A

A. Synthesis of pentoses and NADPH
C. Energy transformation
D. Membrane and nerve conduction

9
Q
Which of the following is the best source of riboflavin?
A. Sunflower seeds 
B. Meat 
C. Milk and milk products 
D. Fruits/vegetables
A

C. Milk and milk products

10
Q
Which of the following is not a role of flavoproteins in intermediary metabolism?
  A. Synthesis of pentoses and NADPH 
  B. Production of a folate coenzyme 
  C. Glutathione reduction 
  D. Beta-oxidation of fatty acids
A

A. Synthesis of pentoses and NADPH

11
Q

Which of the following is not a role of NADPH?
A. Cholesterol and steroid hormone synthesis
B. Production of a folate coenzyme
C. Synthesis of precursors of DNA
D. Beta-oxidation of fatty acids

A

D. Beta-oxidation of fatty acids

12
Q
Which of the following amino acids is a precursor to niacin?
  A. Tryptophan 
  B. Phenylalanine 
  C. Leucine 
  D. Valine
A

A. Tryptophan

13
Q
Side effects arising from using niacin in therapeutic amounts may include all of the following effects except one. Which one?
  A. Elevated plasma glucose 
  B. Liver injury 
  C. Heartburn 
  D. Increased uric acid levels 
  E. Headaches 
  F. Increased blood pressure
A

F. Increased blood pressure

14
Q

Large doses of vitamin B3 as nicotinamide (niacinamide) do not possess the hypocholesterolemic effects of nicotinic acid (niacin), but also do not appear to have as high a potential for toxicity.
A. True
B. False

A

A. True

15
Q
Synthesis of coenzyme A starts with the phosphorylation of which vitamin?
  A. thiamin 
  B. nicotinamide 
  C. pantothenic acid 
  D. biotin 
  E. riboflavin
A

C. pantothenic acid

16
Q
The activity of erythrocyte glutathione reductase is useful for assessing the adequacy of which vitamin?
  Thiamin 
  Niacin 
  Pantothenic acid 
  Riboflavin
A

Riboflavin

17
Q
The activity of erythrocyte transketolase is useful for assessing the adequacy of which vitamin?
  Thiamin 
  Niacin 
  Pantothenic acid 
  Riboflavin
A

Thiamin

18
Q
Which vitamin uses the AI recommendation for adult recommendation because there is insufficient available data to establish an RDA? 
  Thiamin 
  Riboflavin 
  Niacin 
  Pantothenate
A

Pantothenate

19
Q
Excretion of fluorescent orange yellow urine follows oral ingestion of which vitamin?
  Pantothenic acid 
  Thiamin 
  Niacin 
  Riboflavin
A

Riboflavin

20
Q
Which of the following, if any, is not involved in the pyruvate dehydrogenase complex?
  Niacin 
  Riboflavin 
  Pantothenic acid 
  Thiamin 
  All of these are involved
A

All of these are involved

21
Q
Which of the following B vitamins has a Tolerable Upper Intake Level set due to concerns about side effects?
  Riboflavin 
  Pantothenic acid 
  Niacin 
  Thiamin
A

Niacin

22
Q
Absorption of which vitamin is facilitated by the sodium-dependent multivitamin transporter (SMVT)?
  Thiamin 
  Pantothenic acid 
  Niacin 
  Riboflavin
A

Pantothenic acid

23
Q
Which of the following vitamins has the highest daily requirement in terms of RDA or AI?
  Pantothenic acid 
  Niacin 
  Thiamin 
  Riboflavin
A

Niacin

24
Q

Which of the following statements is true?

Reactive species can be formed during normal physiological processes.
All reactive species in human biology are reactive oxygen species.
Antioxidant supplements have been proven superior to dietary antioxidants for reducing the risk of many diseases.
Glutathione is a more effective antioxidant when it is in an oxidized state, whereas reduced glutathione is not very useful as an antioxidant.

A

Reactive species can be formed during normal physiological processes.

25
Q

Which antioxidant is most effective in rapidly eliminating hydroxyl radicals prior to initiation of oxidative damage?

vitamin C
beta-carotene
vitamin E
vitamin K

A

vitamin C

26
Q

Which antioxidant is most effective in terminating chain-propagation reactions in cell membranes?

vitamin E
vitamin C
beta-carotene
vitamin K

A

vitamin E

27
Q

Which two of the following are reactive oxygen species, but do not fit the definition of a free radical? (Indicate both of the correct answers)

  Superoxide anion 
  Peroxyl radical 
  Singlet oxygen 
  Hydroxyl radical 
  Hydrogen or lipid peroxide
A

Singlet oxygen

Hydrogen or lipid peroxide

28
Q
Respiratory burst refers to the use of which reactive oxygen species by white blood cells to destroy foreign microbes?
  Hydroxyl radical 
  Peroxyl radical 
  Superoxide 
  Peroxynitrite
A

Superoxide

29
Q
Which of the following is not a source of hydrogen peroxide production in the human body?
  Tissue ischemia after injury 
  Elimination of superoxide radicals 
  Peroxisome activity 
  Glutathione peroxidase activation
A

Glutathione peroxidase activation

30
Q
The Fenton reaction involves the production of hydroxyl radical by the interaction of hydrogen peroxide with \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_.
  copper 
  iron 
  singlet oxygen 
  superoxide
A

iron

31
Q

Which reactive species is considered a major initiator of lipid peroxidation in the body?

Hydroxyl radical
Singlet oxygen
Hydrogen peroxide
Superoxide

A

Hydroxyl radical

32
Q

Which three of the following minerals are necessary to the optimal performance of superoxide dismutase in human tissues?

 Selenium 
  Zinc 
  Copper 
  Manganese 
  Iron
A

Zinc
Copper
Manganese

33
Q

The reactive species scavenging function of vitamin C is limited to reducing radical species, it does not scavenge or quench any non-radical species.
True
False

A

False

34
Q
Which one of the following minerals is essential to the function of glutathione peroxidase?
  Zinc 
  Iron 
  Manganese 
  Copper 
  Selenium
A

Selenium

35
Q
What is the role of glutathione in the reaction between glutathione peroxidase and various peroxide species?
  Hydrogen acceptor 
  Hydrogen donor 
  Electron acceptor 
  Component of enzyme protein sequence
A

Hydrogen donor

36
Q
Which reactive species is referred to as an "electronically excited" molecule, and is inactivated by a process called "quenching"?
  Peroxyl radical 
  Singlet oxygen 
  Lipid peroxide 
  Superoxide
A

Singlet oxygen

37
Q
Which B-vitamin functions as a coenzyme to regenerate oxidized glutathione?
  Vitamin B6 
  Folic acid 
  Thiamine 
  Niacin
A

Niacin

38
Q

Which of the following statements is true?
An important distinction between the two fat-soluble antioxidants beta-carotene and vitamin E may be that beta-carotene functions more on the cell surface, while vitamin E functions more in the interior of a cell.
The amount of vitamin C intake has little effect on vitamin C absorption.
In general, vitamin C is more effective in lipid environments, while vitamin E is more effective in aqueous environments.
Neither Ester-C nor vitamin C supplements from rose hips appears to be superior to other vitamin C sources.

A

Neither Ester-C nor vitamin C supplements from rose hips appears to be superior to other vitamin C sources

39
Q
Which of the following enzymes is required for the synthesis of vitamin C and not present in human biochemistry?
  Aldonolactonase 
  Gulonolactone oxidase 
  Dehydroascorbate reductase 
  Ascorbyl palmitase 
  Lysyl hydroxylase
A

Gulonolactone oxidase

40
Q
Which of the following foods is not a good source of vitamin C?
  Brussels sprouts 
  Green pepper 
  Broccoli 
  Carrots
A

Carrots

41
Q
Which of the following is the source of hydrogen atoms for the regeneration of ascorbic acid from dehydroascorbate?
  Coenzyme Q 
  FADH 
  Glutathione 
  NADPH
A

Glutathione

42
Q

According to Gropper, the maximal body pool of vitamin C can be maintained with a daily intake of:

100-200 mg
200-400 mg
500-1000 mg
60-100 mg

A

100-200 mg

43
Q
Which reaction is typical of the kind catalyzed by vitamin C?
  Methylation 
  Hydroxylation 
  Decarboxylation 
  Transamination
A

Hydroxylation

44
Q

Vitamin C’s actual participation in biochemical reactions usually involves its antioxidant ability. Choose the description of this activity.
Accepts an electron or electrons to reduce a mineral cofactor
Donates an electron or electrons to oxidize a mineral cofactor
Donates an electron or electrons to reduce a mineral cofactor
Accepts an electron from the quinone form of vitamin E

A

Donates an electron or electrons to reduce a mineral cofactor

45
Q
Which of the following is not a function of vitamin C in human biology?
  Collagen synthesis 
  Norepinephrine synthesis 
  Cholesterol synthesis 
  Serotonin synthesis
A

Cholesterol synthesis

46
Q

The necessity of ascorbic acid for its role in _____ is believed to be the reason that people with scurvy have no energy and are very tired.

carnitine synthesis
creatine synthesis
hormone activation
collagen synthesis

A

carnitine synthesis

47
Q

The result of ascorbic acid interacting with a metalloenzyme containing iron is that the iron is in the _____ form.

ferrous
No answer text provided.
ferric
No answer text provided.

A

ferrous

48
Q
The Tolerable Upper Intake Level for vitamin C was set to help reduce the risk of what side effect of vitamin C supplementation?
  Rebound scurvy 
  Hemochromatosis
  Gastrointestinal upset and diarrhea 
  Kidney stones
A

Gastrointestinal upset and diarrhea

49
Q
Which substance does not belong to the family of carotenoids?
  Alpha-carotene 
  Lycopene 
  Tocotrienol 
  Lutein 
  Canthaxanthin
A

Tocotrienol

50
Q

Match each carotenoid with the foods that represent good sources.

Carrots, cantaloupe
Tomatoes, watermelon
Green leafy vegetables, corn, eggs

A

Alpha and Beat Carotene
Lycopene
Lutein and Zeaxanthin

51
Q

Which of the following best represents foods rich in preformed vitamin A (retinol)?
Citrus fruits, sweet red pepper, broccoli
Most nuts, vegetable oils, green leafy vegetables
Seafood, meat, grains
Cod liver oil, butter, eggs, fortified milk

A

Cod liver oil, butter, eggs, fortified milk

52
Q
Which of the following is not a provitamin A carotenoid?
  Alpha-carotene 
  Lycopene 
  Beta-carotene 
  Beta-cryptoxanthin
A

Lycopene

53
Q
Which of the carotenoids has the greatest vitamin A activity?
  gamma-carotene 
  delta-carotene 
  beta-carotene 
  alpha-carotene
A

beta-carotene

54
Q
Three of the following digestive steps are required for normal absorption of vitamin A to occur in the gastrointestinal tract. Which one is not required?
  Micelle formation 
  Amino acid conjugation 
  Protein hydrolysis 
  Ester hydrolysis
A

Amino acid conjugation

55
Q

Where is the primary site for conversion of provitamin A to vitamin A in the human body?

  Intestinal mucosal cell 
  Adipose cell 
  Liver 
  Intestinal lumen 
  Chylomicron
A

Intestinal mucosal cell

56
Q

Match the substance with the most appropriate storage characteristic.

Post-hepatic circulation via transthyretin
Post-hepatic circulation via VLDL
Primarily stored in the liver
Stored in liver, adipose, and concentrated in specific tissues

Retinol or Carotenoids

A

Retinol
Carotenoids
Retinol
Carotenoids

57
Q

Match the characteristics with the most appropriate substance. Use answers only once.

Most essential for differentiation of epithelial cells
Required for bone development and maintenance
Effective for both free radical quenching AND inhibiting neoplastic transformation

A

retinol
retinol
beta carotene

58
Q
What is the form of vitamin A attached to the protein opsin in a molecule of rhodopsin?
  11-cis retinol 
  11-cis retinal 
  all-trans retinol 
  all-trans retinal
A

11-cis retinal

59
Q
Vitamin A in the form of \_\_\_\_\_\_\_\_ supports the development of cells by influencing gene expression.
  retinol 
  retinal 
  retinoic acid 
  retinyl ester
A

retinoic acid

60
Q

Why is retinoic acid considered a hormone?

It is synthesized in the same tissue that it affects.
It causes the catabolism (break down) of body proteins.
It has a biologic function similar to insulin.
There are receptors for it on the nucleus and it causes a change in protein synthesis.

A

There are receptors for it on the nucleus and it causes a change in protein synthesis.

61
Q
The function of which nutrient most likely includes protecting eye tissues from oxidative damage?
  Lycopene 
  Beta-carotene 
  Lutein/zeaxanthin 
  Retinol
A

Lutein/zeaxanthin

62
Q
Which mineral deficiency interferes with vitamin A metabolism?
  Magnesium 
  Zinc 
  Copper 
  Iron
A

Zinc

63
Q
Which of the following is not a deficiency symptom for vitamin A?
  Xeropthalmia 
  Keratinization 
  Hemolytic anemia 
  Night blindness
A

Hemolytic anemia

64
Q

Which symptom of a vitamin A deficiency is most likely responsible for deficiency-related deaths?

its function as a teratogen
severe infections
keratinization of the cornea
poor cellular differentiation and growth

A

severe infections

65
Q

In which of the following conditions is plasma retinol NOT a good reflection of vitamin A status?

Stores of vitamin A are partially depleted
Stores of vitamin A are exhausted
Stores of vitamin A are filled to capacity

A

Stores of vitamin A are partially depleted

66
Q
For which group are large doses of beta-carotene not likely to be safe?
  diabetics 
  people with low thyroid function 
  smokers 
  people with acute infections
A

smokers

67
Q

The upper limit for a safe amount of vitamin A has been suggested to be 3000 micrograms per day. How much would this be in International Units?

1000 IU
3000 IU
10,000 IU
30,000 IU

A

10,000 IU

68
Q
Which of the following is not a sign of vitamin A toxicity?
  Liver damage 
  Skin irritations 
  Headache 
  Bone pain 
  Elevated blood pressure
A

Elevated blood pressure

69
Q

An individual with poor vitamin A status would have a _____ RDR than someone with a good vitamin A status.

lesser
No answer text provided.
greater
No answer text provided.

A

greater

70
Q

How many vitamers of vitamin E are there?

2 vitamers, D and L
8 vitamers, including tocopherols and tocotrienols
12 vitamers, including acetate and succinate esters
4 vitamers, alpha, beta, delta, gamma

A

8 vitamers, including tocopherols and tocotrienols

71
Q

Which two prefixes indicate a natural, not synthetic, form of vitamin E? (Choose two answers)

SSS
dl-
d-
RRR

A

d-

RRR

72
Q

Which of the following foods is the richest source of dietary alpha-tocopherol?

  Almonds, one ounce 
  Peanuts, one ounce 
  Spinach, 1 cup raw 
  Soybean oil, 1 tablespoon 
  Sunflower oil, 1 tablespoon
A

Almonds, one ounce

73
Q

What biochemical characteristic indicates that a vitamin E supplement must be digested before it can be successfully absorbed?

It is the alpha-tocopherol vitamer
It is the natural stereoisomer
It is esterified to acetate or succinate

A

It is esterified to acetate or succinate

74
Q

After absorption from the intestine, which lipoprotein particle transports most vitamin E from the digestive tract to the liver?

LDL
VLDL
HDL
Chylomicron

A

Chylomicron

75
Q

Alpha-tocopherol has the greatest vitamin E activity in the human body due to a selective preference for this specific vitamer in what part of vitamin E processing?

Intestinal cell chylomicron production
Intestinal lumen digestive enzymes
Intestinal lumen micelle formation and absorption
Hepatic cell production of VLDL

A

Hepatic cell production of VLDL

76
Q

In what type of tissue is the largest amount of vitamin E stored?

heart
liver
adipose
muscle

A

adipose

77
Q

Vitamin E is important to cell membrane stability because it is capable of terminating free radical chain reactions that propagate damage to the phospholipid structure of membranes.

True
False

A

True

78
Q

Regeneration of oxidized vitamin E requires which three cofactors?

  Vitamin C 
  Reduced glutathione (GSH) 
  FADH 
  Selenium 
  NADPH
A

Vitamin C
Reduced glutathione (GSH)
NADPH

79
Q
The latest RDA for vitamin E is expressed in milligrams of RRR-alpha-tocopherol, but most people are more familiar with the older International Units of measurement. What is the adult RDA for vitamin E in International Units if the value is 15 mg of RRR-alpha-tocopherol?
  About 15 IU 
  About 28 IU 
  About 10 IU 
  About 22 IU
A

About 22 IU

80
Q

What type of anemia is associated with vitamin E deficiency?

Microcytic anemia
Megaloblastic anemia
Hypochromic anemia
Hemolytic anemia

A

Hemolytic anemia

81
Q

The Tolerable Upper Intake Level was set for vitamin E to prevent _____________.
Increased risk of birth defects
Increased tendency for bleeding
Increased risk of cancer
Increased tendency for gastrointestinal distress
Increased risk of heart disease

A

Increased tendency for bleeding

82
Q

Regarding food sources of selenium, which of the following statements is false?

Food selenium is primarily in the inorganic form
Soil crops have extremely variable selenium content
Brazil nuts are the richest known source of selenium
Seafood selenium may be less available due to
interactions with mercury

A

Food selenium is primarily in the inorganic form

83
Q

Which form of a) organic and b) inorganic selenium is best absorbed from the gastrointestinal tract?

a) selenomethionine, b) selenate
a) selenocysteine, b) selenate
a) selenocysteine, b) selenite
a) selenomethionine, b) selenite

A

a) selenomethionine, b) selenate

84
Q

Phytic acid (phytate) can inhibit selenium absorption.

True
False

A

True

85
Q

Glutathione peroxidase contains selenium in the form of selenomethionine.

True
False

A

False

86
Q
Which selenium-containing antioxidant is especially effective against reactive nitrogen species such as peroxynitrite?
  Glutathione peroxidase 
  Selenoprotein P 
  Thioredoxin reductase 
  Methionine-R-sulfoxide reductase
A

Selenoprotein P

87
Q

Which of the following is the selenium-containing enzyme important for repairing tissue proteins?

Methionine-R-sulfoxide reductase
Thioredoxin reductase
Selenoprotein P
Glutathione peroxidase

A

Methionine-R-sulfoxide reductase

88
Q

Which selenium-containing molecule is thought to participate in the regeneration of several antioxidant systems, possibly including vitamin C?

Selenophosphate synthetase
Selenoprotein P
Thioredoxin reductase
Selenoprotein W

A

Thioredoxin reductase

89
Q

Selenium-dependent deiodinases are only capable of activating thyroid hormone, not deactivating it.

True
False

A

False

90
Q

Match the statements with the appropriate disease(s).
Keshin or Kashin-Beck

Associated with regional selenium deficiency in China
Symptoms include cardiomyopathy
Symptoms include degeneration of joints and cartilage
Selenium deficiency is not likely the only causative factor

A

Both
Keshin
Kashin-Beck
Both

91
Q

What is the Tolerable Upper Intake Level for selenium?

400 mcg
55 mcg
200 mcg
600 mcg

A

400 mcg

92
Q

Which one of the following assessments is thought to reflect longer-term selenium status than the other assessments?

Urinary selenium
Plasma selenoprotein P
Whole blood glutathione peroxidase activity
Plasma selenium

A

Whole blood glutathione peroxidase activity

93
Q

Which nutrient shows promise as therapy for hypercholesterolemia?

Selenomethionine
Tocotrienols
Alpha-tocopherol
Methyl selenide

A

Tocotrienols

94
Q

Match the biological function with the required nutrient

Transamination
Carboxylation
Conversion of methylmalonyl CoA to succinyl CoA
Decarboxylation

A

B6
Biotin
B12
B6

95
Q
Which of the following, if any, is not involved in one of the pathways of homocysteine metabolism?
  Vitamin B6 
  Vitamin B12 
  Biotin 
  All of the above are involved
A

Biotin

96
Q

Megaloblastic anemia is associated with a deficiency of which micronutrient(s)?

  Biotin 
  Vitamin B6 
  Vitamin B6, biotin, and vitamin B12 
  Both vitamin B6 and vitamin B12 
  Vitamin B12
A

Vitamin B12

97
Q

Microcytic anemia is associated with a deficiency of which micronutrient(s)?

  Vitamin B12 
  Both vitamin B6 and vitamin B12 
  Vitamin B6 
  Vitamin B6, biotin, and vitamin B12 
  Biotin
A

B6

98
Q

The normal digestion and absorption of cobalamin requires adequate ______ digestion in the stomach; the presence of 2 nonenzymatic proteins: ________ ; and a receptor located in the ________.

A

Protein
R protein and intrinsic factor
ileum

99
Q
Which mineral is a component of vitamin B12?
  Vanadium 
  Cobalt 
  Iron 
  Silicon
A

Cobalt

100
Q
The primary site for storage of vitamin B12 in the body is \_\_\_\_\_\_\_\_\_\_\_\_.
  bone 
  muscle 
  spleen 
  heart 
  liver
A

Liver

101
Q

Which of the following is TRUE?

Pernicious anemia can be treated with pharmacological doses of vitamin B12
Inadequate dietary intake, not inadequate absorption, is the most frequent cause of B12 deficiency seen in the US.
Neurological symptoms are uncommon in vitamin B12 deficiency
Pernicious anemia is caused by inadequate protein digestion

A

Pernicious anemia can be treated with pharmacological doses of vitamin B12

102
Q

In the enzyme methionine synthase, vitamin B12 acts by accepting a ________ group from ________ and donating this group to ________ to form methionine.

A

Methyl
5-methyl THF
homocysteine

103
Q

Which one of the following groups does NOT have a higher risk B12 deficiency?

People over 50 years of age
People regularly exposed to nitrous oxide gas
People with gallbladder disease
People with impaired pancreatic exocrine function
People using gastric acid-reducing drugs long-term
People with atrophic gastritis

A

People with gallbladder disease

104
Q

Match the vitamin to the statement about Tolerable Upper Level of Intake.

Folic acid
Vitamin B12
Vitamin B6

A

No tolerable limit
No tolerable limit
Set to limit neuropathy

105
Q

What disease or condition results from an absence or insufficient activity of the branched-chain alpha-keto acid dehydrogenase enzyme complex?

Cataracts
Maple Syrup Urine Disease
Cheilosis
Beriberi

A

Maple Syrup Urine Disease

106
Q

Biotin status has been shown to decline in some women.

True
False

A

True

107
Q

Absorption of which vitamin is facilitated by the sodium-dependent multivitamin transporter (SMVT)?

Biotin
Folate
Vitamin B12

A

Biotin

108
Q

Acetyl CoA carboxylase depends on which B vitamin to begin fatty acid synthesis?
Vitamin B12
Folate
Biotin

A

Biotin

109
Q

What is meant by the term folate that distinguishes it from folic acid?

Folate is the oxidized form of the vitamin found naturally in foods and in biological tissues
Correct!
Folate is the reduced form of the vitamin found naturally in foods and in biological tissues
Folate is the oxidized form of the vitamin found in fortified foods and most supplements
Folate is the reduced form of the vitamin found in fortified foods and most supplements

A

Folate is the reduced form of the vitamin found naturally in foods and in biological tissues

110
Q
Mammals are unable to synthesize folic acid, even though they can accomplish several of the necessary steps. Which one of the following is the step that cannot be accomplished by mammals? 
  Cannot synthesize pteridine 
  Cannot synthesize PABA 
  Cannot form pteroic acid 
  Cannot synthesize glutamic acid
A

Cannot form pteroic acid

111
Q
Folate in foods can only be absorbed in the monoglutamate form; therefore, digestive enzymes called \_\_\_\_\_ are important for folate nutriture.
  glutaminases 
  peptidases 
  lipases 
  conjugases
A

conjugases

112
Q

Which of the following best describes the general biochemical role for folate?

One-carbon transfer
Oxidative decarboxylation
gamma-carboxylation
Electron transfer

A

One-carbon transfer

113
Q

Dietary folate equivalents (DFE) are needed to account for the variation in bioavailability among different forms of folate. Based on the DFE, which of the following forms is most available?

Natural food folate
Synthetic folic acid taken on an empty stomach
Synthetic folic acid in a fortified food
No answer text provided.

A

Synthetic folic acid taken on an empty stomach

114
Q

Which type of anemia is associated with folate deficiency?

Megaloblastic anemia
Hemolytic anemia
Hypochromic anemia
Microcytic anemia

A

Megaloblastic anemia

115
Q

Match the branch of nutritional genomics with the correct description.

  • Genetic alterations that can be compensated for by increasing or decreasing specific nutrients
  • Inborn changes in DNA nucleotide sequences or gene variants
  • The interactions among genes and bioactive components in food that change gene expression without changing the DNA nucleotide sequence
A

Nutrogenomincs
Nutrogenetics
Nutritional epigenetics

116
Q

The primary mechanism by which gene expression is modified by bioactive factors in food appears to be _____.
downregulation of translation
mutations causing cancer
production of SNPs
interactions with transcription factors

A

interactions with transcription factors

117
Q

What lifestyle change would be most important to individuals with a common variant in the GST gene that impairs protections against toxins?
increasing levels of daily exercise
increasing intake of omega-3 fats
increasing ingestion of cruciferous vegetables
eating a low-fat diet

A

increasing ingestion of cruciferous vegetables

118
Q

Match the genotype for N5,N10 methylene tetrahydrofolate reductase (MTHFR) with the appropriate description.

MTHFR 677CC
MTHFR 677CT
MTHFR 677TT

A

Homozygous genotype exhibiting 30-35% of normal enzyme activity
Heterozygous exhibiting 70% of normal activity
Homozygous genotype exhibiting 100% of normal enzyme activity

119
Q

Which two of the following can function as methyl donors? (Choose two answers)

Folic acid
5-methyl folate
Betaine
Choline

A

5-methyl folate

Betaine

120
Q
The vitamin D response element (VDRE) is found
  on the cell membrane. 
  in the mitochondria. 
  in the cell cytosol 
  in the nucleus.
A

in the nucleus.

121
Q
Which of the following risk factors is not associated with a vitamin D deficiency?
  Aging 
  Antibiotic therapy 
  Kidney disorders 
  Crohn's disease
A

Antibiotic therapy

122
Q
Which is not a characteristic of rickets?
  Thoracic deformities 
  Deformed fingers 
  Curved spine 
  Bowed legs
A

Deformed fingers

123
Q
For what type of enzyme does vitamin K act as a cofactor?
  decarboxylase 
  coagulase 
  hydroxylase 
  carboxylase
A

carboxylase

124
Q
Vitamin-K dependent modification of proteins such as the clotting factors affects the binding of which mineral ion by those proteins?
  Magnesium ions 
  Iron (ferrous) ions 
  Phosphate ions 
  Calcium ions
A

Calcium ions

125
Q

Match the following characteristics with the appropriate mineral

Dietary sources include soft drinks
Poorly absorbed from oxalate-containing foods
Component of chlorophyll in green leafy vegetables
Absorption at low intakes does NOT rely on a brush border transporter
Digestion not required for dietary forms

A
Phosphorus
Calcium
Magnesium
Phosphorus
Magnesium
126
Q

Calcium absorption in adults is typically less than 50%, whether from food or supplements.

True
False

A

True

127
Q
The binding protein that facilitates many calcium-dependent physiological processes is \_\_\_\_\_\_\_\_\_\_\_
  albumin 
  calmodulin 
  calcitonin 
  osteocalcin
A

calmodulin