PHRM 825: Micronutrition Flashcards
(145 cards)
1
Q
Estimated average requirement (EAR) definition
A
The amount of nutrient estimated to meet the need of 50% of the healthy individuals in an age and gender group
2
Q
Recommended dietary allowance (RDA) definition
A
- Two standard deviations above the EAR
- Sufficient to meet the need of nearly all (97-98%) healthy individuals in a group
3
Q
Adequate intake (AI) definition
A
- Used when scientific evidence is inadequate to set an EAR
- Approximations of the average nutrient intake by a healthy population
4
Q
Tolerable upper intake level (UL) definition
A
Max level of daily intake of a nutrient without any health risk
5
Q
Food and Nutrition Board of the National Research Council meets every _____ years to make recommendations on dietary reference intakes
A
6-10
6
Q
List of fat-soluble vitamins
A
A, D, E, K
7
Q
Deficiency of fat-soluble vitamins is ____
A
Rare
8
Q
List of water-soluble vitamins
A
Vitamin B’s and vitamin C
9
Q
Water-soluble vitamins are readily excreted in ____
A
urine
10
Q
List of macrominerals
A
Ca+2, Mg+2
11
Q
Trace minerals list
A
Iron, iodine, zinc, copper, selenium, chromium, manganese, molybdenum, fluoride, boron
12
Q
Vitamin definition
A
Organic compounds that are essential in the diet to promote and regulate body functions
13
Q
How were vitamins named?
A
In the order of their discovery
14
Q
Fat-soluble and water soluble vitamins are grouped into 2 different groups that share similar ___, ___, and ___ properties
A
absorption, excretion, and storage
15
Q
Vitamin A is produced from ____
A
Carotenoids
16
Q
Vitamin A deficiency may cause ____
A
Night blindness
17
Q
Vitamin A is also known as
A
Retinol, retinal, and retinoic acid
18
Q
Delta-cis-retinal reversibly associates with ____ and function as _____
A
opsins; light sensor
19
Q
What gives carrots their orange color and what vitamin does it come from?
A
Beta-carotine; Vitamin A
20
Q
What gives carrots their orange color and what vitamin does it come from?
A
Beta-carotine; Vitamin A
21
Q
Retinoic acid function as _____, regulating _____
A
steroid hormone; cell growth and differentiation
22
Q
Retinoic acid associates with 2 _____
A
Nuclear receptors
23
Q
The names of the nuclear receptors that retinoic acid associates with are
A
Retinoic acid receptors (RARs) and retinoic X receptors (RXR)
24
Q
Carotenoids are effective _____ and may reduce the risk of _____
A
Antioxidante; cancers
25
Vitamin A is stored in the ____ as ____
Liver as retinol palmitate
26
Dietary sources of vitamin A
dark green and yellow vegetables, liver, egg yolk, butter, and whole milk
27
Vitamin A deficiency is ____
Rare
28
Americans consume less than ____ of the recommended daily value of vitamin A
2/3
29
Vitamin D functions as ____ maintaining ______ homeostasis
steroid hormones; calcium
30
Vitamin D is synthesized from an intermediate in
cholesterol synthesis
31
Which vitamin is produced photochemically in the skin
Vitamin D
32
Insufficient exposure to sunlight may cause _____ deficiency
Vitamin D
33
Vitamin D deficiency causes ____ in children and ____ in adults
Rickets and osteomalacia
34
Dietary sources of vitamin D
Vitamin D milk, saltwater fish, liver, egg yolk
35
Vitamin D occurs in the diet as ____ and ____
tocopherols and tocotrienols
36
Vitamin E is a naturally occurring _____ which protects ____
antioxidant; unsaturated fatty acids
37
Vitamin E accumulates in what?
- Circulating lipoproteins
- Cellular membranes
- Fat deposits
38
Vitamin E reduces the risk of _____ by preventing _____
Cardiovascular disease; oxidation of LDL
39
The oxidized form of LDL is
Atherogenic
40
Dietary sources of Vitamin E
Vegetable oils rick in polyunsaturated fatty acids
41
Deficiencies of Vitamin E are ____
rare
42
Which vitamin is required for post-translational modification of glutamic acid residues to gamma-carboxyglutamic acid residues?
Vitamin K
43
Carboxyglutamic acids allow proteins to bind to ___
calcium
44
Which vitamin is essential for blood clotting?
Vitamin K
45
Several proteins involved in blood coagulation require gamma-carboxyglutamic acid for _____
calcium binding
46
Which vitamin is essential for bone mineralization
Vitamin K
47
Several proteins in bone require gamma-carboxyglutamic acid residues for binding to ____
hydroxyapatite
48
In the carboxylation reaction, vitamin K is converted to ____
an inactive epoxide form
49
Regeneration of the active vitamin K form from the inactive expoide form requires what enzyme?
Vitamin K epoxide reductase
50
Warfarin is a ____ antagonist
Vitamin K
51
Warfarin prevents ____
thrombosis
52
Warfarin inhibits what enzyme?
Vitamin K epoxide reductase
53
Dietary sources of Vitamin K1
Green vegetables
54
Dietary sources of Vitamin K2
Intestinal bacteria
55
Vitamin K deficiency is ___
rare
56
Thiamin is rapidly converted to ____ and ____
Thiamin pyrophosphate and thiamin triphosphate
57
Thiamin pyrophosphate function as a cofactor in ____
enzymatic catalysis (e.g. thiazole ring forms a carbanion, a strong nucleophile)
58
Thiamin triphosphate functions in ______ in ____
transmission of nerve impulse in peripheral nerve membranes
59
Severe thiamin deficiency is known as what?
Beriberi
60
Severe thiamin deficiency is characterized by what
Muscular atrophy and weakness
61
Thiamin deficiency occurs in populations that ____
Exclusively rely on polished rise for food or in alcoholics
62
Riboflavin is a precursor of ____ used in ____
cofactors; redox reactions
63
2 riboflavin derived molecules
Flavin adenine dinucleotide (FAD) and flavin mononucleotide (FMN)
64
Riboflavin deficiency is ___
Very rare
65
Symptoms of riboflavin deficiency
Angular cheilitis, glossitis, and scaly dermatitis
66
Riboflavin deficiency is typically seen in
chronic alcoholics
67
Dietary sources of riboflavin
Milk, meat, eggs, and cereal products
68
Niacin exists in what 2 forms in the diet?
Niacin (nicotinic acid) and niacinamine (nicotinamide)
69
Niacin is converted to what cofactors?
NAD adn NADP
70
NAD and NADP are what?
Electron acceptors or hydrogen donors
71
NAD and NADP are essential in _____ reactions and _____
Redox reactions and cellular respiration
72
Severe niacin deficiency is known as
Pellagra
73
Niacin deficiency presents as
dermatitis, diarrhea, and dementia
74
Niacin defiency is ____
rare
75
Niacin deficiency is typically seen in what patients?
Alcoholics, patients with severe malabsorption, and elderly on very restrictive diets
76
Dietary sources of niacin
Meats, peanuts, and enriched cereals
77
Pyridoxine is also known as what?
Vitamin B6
78
Pyridoxine exists in what forms in the diet?
Pyridoxine, pyridoxamine, pyridoxal
79
Pyridoxine is converted to what cofactor
Pyridoxal phosphate
80
Pyridoxal phosphate acts as a coenzyme in what 3 reactions?
- Transamination reactions in amino acid metabolism
- Synthesis of neurotransmitters
- Synthesis of sphingolipids
81
Symptoms of mild pyridoxine deficiency
Irritability, nervousness, and depression
82
Symptoms of severe pyridoxine deficiency
Peripheral neuropathy and convulsions
83
Dietary sources of pyridoxine
Meat, vegetables, and whole-grain cereals
84
Biotin serves as a cofactor for activation of ____ in _____
carbon dioxide; carboxylase enzymes
85
Biotin is ____ bound to _____ in enzymes
covalently; lysine side chains
86
Dietary sources of biotin
Rich in a wide range of food sources
87
Biotin deficiency is ___
rare
88
Biotin deficiency may occur when
- Raw egg whites are consumed regularly (avidin in egg white forms a tight complex with biotin)
- Pregnant women tend to have a high risk of biotin deficiency
89
Folic acid is converted to _____
Tetrahydrofolate
90
Tetrahydrofolate is
a one-carbon carrier in enzyme reactions
91
Folic acid is used in the synthesis of ___ and ___
Amino acids and nucleotides
92
Folic acid is essential for ____ synthesis and _____
DNA synthesis and cellular proliferation
93
Dietary source of folic acid
Rich in a wide range of food sources
94
Folic acid deficiency does what
- Inhibits DNA synthesis
- Produces abnormal red blood cells (anemia)
- Increases the risk of birth defects, especially neural tube defect
95
Folic acid deficiency is common in what kinds of people
Alcoholics
96
Vitamin B12 is also known as
Cobalamin
97
Vitamin B12 contains ___ in a coordination state of ___
CO; six
98
Vitamin B12 is required for what 2 reactions in humans
- Methionine synthase (homocysteine --> methionine)
| - Methylmalonyl-CoA mutase (methylmalonyl-CoA --> syccinyl-CoA)
99
When vitamin B12 is insufficient ___ and ___ accumulate, causing ___ and ____
homocysteine and methylmalonic acid; anemia and neurological damage
100
Vitamin B12 deficiency is rare except in patients with ____ and ____
Severe malabsorption diseases and long-term vegetarians
101
Vitamin C is also known as ___
ascorbic acid
102
Vitamin C functions as a cofactor for several ___
oxidases
103
Vitamin C is required for ____ and ____, which is necessary for ____
hydroxylation of lysine, proline side chains, collagen stability
104
Proper collagen stability is essential for what 3 things
Maintenance of normal connective tissue, wound healing, and bone formation
105
Vitamin C is a _____
nonenzymatic reducing agent
106
Vitamin C aids in absorption of _____ by reducing it to ____ in the ____
iron; Fe+2; stomach
107
Vitamin C protects what 3 vitamins from oxidation?
Vitamins A, E, and some B
108
Mild vitamin C deficiency causes ____ which can lead to ____
Capillary fragility; easy bruising and decreased immunocompetency
109
What is the most abundant mineral in the body?
Calcium
110
Calcium is used for what?
- Making bones
- Serving as a second messenger
- Required for many enzymes
- Essential for blood coagulation and muscle contractility
111
Maintenance of constant serum levels of this mineral is vital
Calcium
112
An elaborate homeostatic control system exists for what mineral?
Calcium
113
Bones serve as a reservoir for what mineral?
Calcium
114
Dietary insufficiency results in net loss of ____ from the bones
Ca+2
115
_____ is required for optimal utilization of Ca+2
Vitamin D
116
Exercise facilitates calcium utilization for ____
bone formation
117
Symptoms of ____ deficiency resembles _____ deficiency
Calcium; vitamin D
118
Calcium deficiency may contribute to ____
osteoporosis
119
Achieving maximum bone density from age ___ to ___ is critical in reducing the risk of ___ later
10 to 35; osteoporosis
120
Proper calcium intake from the diet and exercise maximizes ____
bone density
121
Mild calcium deficiency may cause _____
muscle cramps
122
Dietary sources of calcium
- Dairy products
| - Nuts, beans, seeds, and seaweeds
123
Iron is a component of what?
Heme, cytochromes, and nonheme iron proteins
124
Iron is required for what?
O2 transport, energy metabolism, cell proliferation, and immune defense
125
What increases the need of iron?
Blood loss including menstruation
126
Menustruating females need _____ more iron than adult males
2-fold
127
Iron homeostasis is ___ regulated
tightly
128
Iron homeostasis is ___ for life but also _____
essential; extremely toxic
129
Free iron generates ____
free radicals
130
Iron is normally sequestered in the cell by ____ and in the blood by ____
ferritin; transferrin
131
Iron-deficiency anemia is widespread in ____ and ____
Children and menstruating females
132
Iodine is used for synthesis of ____
thyroid hormones
133
What is the best natural food source for iodine?
Seafood
134
Iodine deficiency was an endemic in ____ populations
inland
135
Goiter definition
An enlargement of the thyroid gland caused by iodine deficiency
136
Cretinism definition
Severely stunted physical and mental growth caused by iodine deficiency
137
What mineral is routinely added to table salt?
Iodine
138
Zinc is required for many ____ and ____
Metalloenzymes and zinc finger proteins
139
Zinc deficiency in children results in ___ and ____
poor wound healing, dermatitis, and impaired immune function
140
Copper is required for many ____
enzymes
141
Copper deficiency may cause what?
Anemia, bone demineralization, and blood vessel fragility
142
Selenium is incorporated into _____ selenoproteins in humans
~25
143
Selenoproteins contain _____, which are incorporated durign translation
Selenocystein residues
144
Selenocystyl-tRNA binds to ____ codons in mRNA with a special sequence in 3'-untranslated region
UGA
145
Selenium deficiency is ___
rare
