Vitamins and Minerals Flashcards
1
Q
The most widely used method of assessing vitamin B6 status is by the activation of ______________ by pyridoxal phosphate added in vitro, expressed as the ________________.
A
erythrocyte transaminases
activation coefficient
2
Q
In Excess, Vitamin B6 Causes:
A
Sensory Neuropathy
3
Q
There is some slight evidence that taking 2 to 7 g of pyridoxine per day is effective in treating:
A
premenstrual syndrome
4
Q
VITAMIN ____ IS FOUND ONLY IN FOODS OF ANIMAL ORIGIN
A
B12
5
Q
Deficiency state that results from inadequate absorption
A
Secondary
6
Q
Deficiency state that results from increased requirement
A
Secondary
7
Q
Deficiency state that results from inadequate intake
A
Primary
8
Q
Deficiency state that results from medication
A
Secondary
9
Q
The nine B vitamins are considered as:
water soluble or fat soluble?
A
water soluble
(B1, B2, B3, B5, B6, B7, B9, B12)
also Non-B complex (ascorbic acid/ vitamin C)
10
Q
Which classification of vitamins are mostly converted to co-enzymes and are used in metabolic pathways and hematopoiesis?
A
Water-soluble
11
Q
Fat soluble vitamins are only absorbed with:
A
fatty acids, bile, and pancreatic secretions
12
Q
Which classification of vitamins can be stored in the liver and adipose tissue?
A
Fat soluble
13
Q
Which fat soluble vitamin has a coenzyme function?
A
Vitamin K
14
Q
Which classification of vitamins is more likely to cause toxicity with overdose or megadose?
A
Fat-soluble
15
Q
Which classification of vitamins is needed in frequent doses?
A
Water-soluble
16
Q
Which classification of vitamins is needed in periodic doses (weeks to months)?
A
Fat-soluble
17
Q
True or False:
Minerals regulate enzyme activity
A
true
18
Q
True or False:
Minerals maintain acid balance and osmotic pressure
A
True
19
Q
Which of the following is not characterized by minerals?
A. Facilitates membrane transfer of essential compounds
B. Helps in maintaining nerve and muscular activity or irritability
C. May be structural constituents to body tissue
D. Involved directly in the growth process
E. Regulates enzyme activity
A
D. involved INDIRECTLY in the growth process
20
Q
Macrominerals are essential at levels ____ mg/day for adults
A
100 mg/day
21
Q
Required intake of Trace elements is less than ____ mg/day
A
1000
22
Q
Which of the following is a macromineral? A. Magnesium B. Manganese C. Chylomicron D. Copper
A
A. Magnesium
→ Macrominerals are calcium, phosphorus, magnesium, sulfur, sodium, potassium, chloride
23
Q
Which of the following trace elements has no clear function? A. Cobalt B. Molybdenum C. Silicon D. Selenium
A
C. Silicon
Essential trace elements, function not clear
▪ Silicon, vanadium, nickel, tin, cadmium
24
Q
Which macrominerals are important for tissue/bone structure?
A
Calcium
Magnesium
Sulfur
25
Which macrominerals are important for membrane function and have regulatory roles?
Sodium
Potassium
Chloride
26
Which trace element, though essential but with no clear function, is quite toxic in excess?
Cadmium
27
Main active form of Vitamin A
retinol (all-trans-retinol)
28
What are the other active forms of Vit A apart from retinol?
▪ Retinaldehyde (instead of OH group, has an aldehyde)
▪ Retinoic acid (all-trans retinoic acid; carboxyl group)
▪ Beta-carotene
29
Precursor of vitamin A
carotenoids or carotenes
30
The most important precursor of Vit A
beta-carotene
31
Which vitamin is formed from cryptoxanthines?
Vit A
32
Beta-carotene (carotenoids) is cleaved in the intestinal mucosa by ______ forming retinaldehyde or retinoic acid
carotene dioxygenase
33
lipoprotein that carries retinol to the liver
Chylomicron
34
Beta-ionone ring is found in which vitamin?
Vitamin A
35
True or False:
| Conversion of carotenoids to retinol is nearly 100%
True
36
Which fat-soluble vitamin is important for the synthesis of transferrin?
Vit A
37
Which fat-soluble vitamin functions for Growth and maintenance of epithelial tissues?
Vit A (Retinol and retinoic acid)
38
Amino acid residue of opsin for combination with 11-cis retinal?
Lys
39
Which vitamin A receptor binds both all-trans-retinoic acid and 9-cis-retinoic acid?
retinoic acid receptor (RAR)
40
Which vitamin A receptor binds only 9-cis-retinoic acid?
retinoid X receptor (RXR)
41
__________ is a chain-breaking antioxidant that acts on radicals derived from PUFAs (Polyunsaturated fatty acids) in lipid peroxidation
β-carotene
42
True or False:
| Vitamin A has a role in the differentiation of immune cells.
True
43
Foods that normally have pre-formed retinol
→ Liver, egg yolk, milk, butter
44
Main sources of carotenoids:
→ mainly from plant sources – dark green and yellow vegetables, tomatoes, sweet potatoes, oily fruits, and red palm oil
45
Vitamin deficiency of patient with abnormal dryness of the conjunctiva and cornea of the eye with inflammation with ridge formation (leading to total blindness)
Vit A (xerophthalmia = keratinization of cornea)
46
Vitamin A deficiency can be biochemically equivalent to which type of anemia?
Iron-deficiency anemia
| but in the presence of adequate iron intake
47
Deficiency of which form of vitamin A can repress gene expression?
9-cis retinoic acid
48
Added micrograms retinol equivalent for lactating mothers
400
49
Added micrograms retinol equivalent for pregnant women
300
50
Patient presented with inflamed lips, bone pain (possible hip fracture or calcification), scaly dermatitis, enlargement of liver and spleen, nausea, and diarrhea. What vitamin state should be assessed?
Excess Vitamin A or Hypervitaminosis A
51
Initial sign of Hypervitaminosis A
Cheilitis (inflammation of lips) or dry lips
52
True or False:
| Free vitamin A in circulation doesn't usually cause membrane lysis and tissue damage
False:
| Unbound vitamin A can cause membrane lysis and tissue damage
53
Headache, nausea, ataxia, anorexia is expected in hypervitaminosis A due to:
Increased cerebrospinal fluid pressure
54
Precursors of Vitamin D
→ 7-dehydrocholesterol (animals)
| → ergosterol (plants)
55
Active form of Vit D
1, 25 dihydroxycholecalciferol
| also called calcitriol
56
How is calcidiol formed
Hydroxylation of cholecalciferol (Vit D3) in the liver
Calcidiol is aka 25-OHD or 25-hydroxycholechalciferol
57
Hydroxylation at which carbon yields an inactive dihydroxyvitamin D
24
58
Which form of vitamin D is present in the circulation and is used to measure in the laboratory for Vit D assay?
Calcidiol or 25-OHC or 25-hydroxycholcalciferol
59
Overall effect of calcitriol in the body in terms of macrominerals is:
increased plasma calcium and phosphate
60
Calcitriol is involved in the following processes EXCEPT
A. Modulation of cell proliferation
B. Increase production of interleukins
C. Insulin secretion
D. Synthesis and secretion of parathyroid and thyroid hormones
E. T-lymphocyte and immunoglobulin production by B-cells
B. should be → inhibition of production of interleukins
61
Vitamin D potency:
| 1 mcg cholecalciferol or ergocalciferol is equal to ___ IU
40 IU
62
True or False:
| RDA for Vit D increases with age
```
True
• Infants (months, μg)
→ 0-11: 5 (♂, ♀)
• Children (years, μg)
→ 1-18: 5 (♂, ♀)
• Adults (years, μg)
→ 19 – 49: 5 (♂, ♀)
→ 50-59: 10 (♂, ♀)
→ 60 ->70: 15 (♂, ♀)
```
63
True or False:
| There is NO added requirements for Vit D for pregnant and lactating mothers
True
64
How are foods fortified with ergosterol (D2)?
irradiating ergosterol from yeast
| e.g., milk and butter
65
What form of Vit D is absorbed from plants such as mushrooms?
ergocalciferol
66
True or Fals:
| One food source of Vit D is freshwater fish
False:
Should be
• Saltwater fish (salmon, sardines, and herring), liver and egg yolk
67
The most common symptoms of vitamin D deficiency in young children
Rickets
68
The most common symptoms of vitamin D deficiency in adults
osteomalacia
69
Condition of under mineralized osteoid matrix resulting into soft, pliable bones due to poor Ca++ absorption in children
Rickets
70
Condition known as softening of bones due to demineralization of intact bone matrix
Ostomalacia
71
Recommended Vit D IU in 60–70-year-olds to prevent osteoporosis
600 IU or 15mcg
72
```
A chronic alcoholic patient is at risk of having deficiency with the following EXCEPT:
A. Vit D
B. Bit B2
C. Vit B7
D. Vit B1
E. NOTA
```
E. NOTA
72
```
A chronic alcoholic patient is at risk of having deficiency with the following EXCEPT:
A. Vit D
B. Bit B2
C. Vit B7
D. Vit B1
E. NOTA
```
E. NOTA
73
____________ stimulate the conversion of vitamin D to inactive metabolites and have been shown to cause bone demineralization when used for long periods of time
Corticosteroids
74
```
The following characterizes excess of vit D EXCEPT:
A. blood vessel contraction
B. high BP
C. due to excessive sunlight exposure
D. calcinosis
```
C. Excessive sunlight exposure does not lead to vitamin D poisoning
75
Secondary hyperparathyroidism may occur with deficiency to which vitamin?
Vitamin D
76
T/F:
| Phosphate-binding drugs are also given in patients with Ca++ deficiency
True
77
Most active form of Vit E
D-alpha tocopherols
78
The most potent form of vit E and is used as the measure of potency.
D-alpha-tocopherol
79
Synthetic form of Vit E but not as potent as naturally occurring compounds
DL-alpha -tocopherol
80
The least toxic fat-soluble vitamin but may result to hemorrhage in case toxicity happends
Vit E
81
How does Vit E enhance heme synthesis?
by increasing the levels of aminolaevulinic acid (ALA) synthetase and ALA dehydratase
82
Although deficiency is virtually non-existent, vitamin E supplementation may be necessary with:
premature infants or in cases of fat malabsorption
83
Best food sources of Vitamin E
Nuts, seeds, vegetable oil
Others: Green leafy vegetables, soybeans, canola, corn
84
There may be increased risk of hemorrhagic stroke in patient with Hypervitaminosis of Vit ___
E
85
Core of vitamin K molecule
naphthoquinone
| → Aromatic ring + quinone unit
86
Most common dietary source of vitamin K
Phylloquinone (K1)
87
Form of Vit K produced by intestinal bacteria in humans
Menaquinone (K2)
88
Because of its lack of the long side chain of the natural vitamins, this form of Vit K is the most active form being 2x as potent
Menadione (K3)
89
Vitamin as Cofactor for the formation of amino acid gamma-carboxyglutamate
Vit K
90
Clotting factors involved with the function of Vitamin K
X, IX, VII, II, proteins C and S
91
Which Calcium-binding proteins is related to Vit K?
* Osteocalcin and matrix Gla-protein (in bone)
* Nephrocalcin (kidney)
* Protein product of the growth arrest specific gene (Gas6), forregulation of differentiation and development in the nervous system and apoptosis in other tissues
92
drugs that interfere with vitamin K metabolism
cephalosporin and high dose salicylates
93
High doses of vitamin K3 can interfere with the function of ______
glutathione
| → Results in oxidative damage to cell membranes
94
Aneurin is aka:
Thiamine (B1)
95
Sulfur is a component of the structure of these vitamins:
B1, B5, B7
96
Which active form of Vit B1 has a role in nerve conduction
Thiamine triphosphate
97
One way of assessing thiamin nutritional status is by activation of ___________ in erythrocyte lyase by TPP
apo-transketolase
98
Thiamine is absorbed in which part of the GIT?
jejunum
99
Anti-stress vitamin
Vit B1
100
Serves as coenzyme for oxidative decarboxylation reactions
Vit B1
101
Vitamin that activates conduction channels in neuroblastoma cells
Vit B1 (Thiamine triphosphate -phosphorylates a chloride channel in the nerve membrane; hence, nerve conduction)
102
```
Which of the following does not involve the function of vit B1?
A. Carbohydrate metabolism (glycolysis)
B. Citric acid cycle
C. Branched Amino Acid Catabolic Pathway
D. PPP
E. NOTA
```
E.
→ Pyruvate dehydrogenase in carbohydrate metabolism
→ Alpha-ketoglutarate dehydrogenase complex in citric acid cycle (TPP for decarboxylation)
→ Branched-chain ketoacid dehydrogenase (BCKAD) in Branched Amino Acid Catabolic Pathway for oxidation
→ Pentose phosphate pathway (TPP acts as a coenzyme in transketolase reaction)
103
Most common effect of thiamin deficiency
Beriberi
104
Ascending peripheral polyneuropathy that affects elderly without cardiac involvement
Dry beriberi
105
Beriberi associated with heart failure in infants and metabolic abnormalities
Fulminating beriberi
| → Aka Shoshin beriberi
106
Alcoholic patient presents with ataxia, imbalances, ophthalmoplegia, nystagmus, and confusion. Which vitamin is probably deficient?
Vit B1
107
Vitamin that is important for Glutathione reductase mediated detoxification
B2: riboflavin
108
T/F: Toxicity does not occur in riboflavin since it is non-toxic even at high oral doses
True
109
Vitamin deficiency manifesting with angular cheilitis
Riboflavin deficiency
110
Patient was manifesting with seborrheic dermatitis and glossitis. Hence, you asked for measurement of the activation of erythrocyte glutathione reductase to test for Vit __ deficiency
B2 (riboflavin)
111
Niacin is synthesized from which AA?
W
112
Vit Source of ADP-Ribose for DNA repair
B3 or Niacin
113
Patient manifests with Pellagra or the triad of dermatitis, dementia and diarrhea. Deficiency is most likely:
Vit B3
114
>____ mg/day of Vit B3 may cause liver damage
500
115
Most active form of Vit B6
Pyridoxal 5’phosphate
116
Prime reservoir of Vit B6
Muscle
117
Vitamin for Transamination and decarboxylation in amino acid metabolism
B6
118
Vitamin for the Formation of sphingolipids and development of myelin sheath
B6
119
Vitamin for synthesis of aminolaevulinic acid (precursor of heme)
B6
120
Vitamin that removes hormone receptor complex from DNA binding site
→ Results to termination of action of hormone
B6
121
Sideroblastic Anemia is seen in Vit ___ deficiency
B6
122
>____mg/day of Vit B6 is associated with nerve damage and sensory neuropathy!
200
123
Vit. B 12 dependent enzymes:
→ Methylmalonyl CoA mutase
→ Leucine aminomutase
→ Methionine synthase
124
More stable form of Vit B12
cyanocobalamin
125
Vit for transfer of methyl groups in the nucleic acid synthesis
B12
126
What releases B12 from its peptide bond in the stomach?
HCl
127
Required for cobalamin absorption in the intestine (ileum)
Intrinsic factor (Castles intrinsic factor)
128
common deficiency in vegetarians
Vit B12
129
B12 deficiency may result in the irreversible degeneration of the spinal cord due to failure of methylation of one of the _______ residue on myelin sheath
arginine
130
Anemia with B12 deficiency
Pernicious anemia
→ B12 deficiency impairs metabolism of folic acid
or Megaloblastic anemia
131
Folic acid in the presence of NAD, is reduced to __________– active form
tetrahydrofolic acid (THFA)
132
Vitamin = pteridine ring
B9
133
Folate is important for the metab of which AA?
Serine/Glycine/Methionine/Histidine
134
Vitamin for the Formation and maturation of RBC and WBC in the bone marrow
B9
135
Maternal _____ deficiency can lead to occurrence of neural tube defects among infants due to inability of closure of the neural tube.
folate (B9)
136
Women who use oral contraceptives have impaired _____ metabolism
folate
137
Vitamin that Blocks degradation of ferritin to hemosiderin
C
138
Vit that acts as a co-enzyme and cofactor in metabolic processes due to its ability to lose or take H+
C
139
Oxidation of phenylalanine to tyrosine is facilitated by Vit ___
C
140
Vit constituent of coenzyme A
B5
141
Vit Important in synthesis of cholesterol, steroid hormones, phospholipids and porphyrin rings
B5
142
Coenzyme for reactions involving the addition or removal of CO2 to and from active compounds:
Biotin (B7)
143
Coenzyme for deamination of AA (Thr and Ser)
Biotin B7
144
Coenzyme/prosthetic group in carboxylation reactions
B7
145
vitamin important for liver gluconeogenesis
B7 - pyruvate carboxylase action
146
Most abundant mineral in the body
Calcium
147
T/F:
| Calcium in Mostly transcellular in duodenum
true
148
Cofactor for prothrombin to thrombin conversion for blood clot formation
Calcium
149
Most common signal transduction element because of its ability to reversibly bind to proteins and to complex with anions
Calcium
150
Hypocalcemia is Serum Ca2+ < ___ mg/dL
8.5
151
Laryngismus:
Hypocalcemia
152
Hypercalcemia is Serum Ca2+ > ___ mg/dL
10.2
153
Most important systemic electrolyte
PHOSPHORUS
154
Normal serum phosphorus is
2.5-4.5mg/dL.
155
Most important metabolic reactions that require Pi is the function of the enxyme:
glycogen phosphorylase
156
Mineral Component of glutathione which has antioxidant properties
Sulfur
157
OVERTOXICITY of ___ causes Osmotic diarrhea and Ulcerative colitis
Sulfur
158
Which parts of the Renal tubules reabsorb Mg
65% in TAL and 30% in DCT
159
Mg++ is absorbed by active transport the intestinal mucosa by a process involving vitamin:
D
160
Renal conservation of magnesium is partly controlled by ___ and ____.
PTH
| aldosterone
161
Deficiency in ___ causes:
| Widening of QRS complex and atrial and ventricular dysrhythmia
Mg++
162
Hypokalemia and hypocalcemia cannot be corrected if the ___ is also low
Mg
163
Hyponatremia
| → Serum Na+ < __ mmol/L
135
164
Hypernatremia
| → Serum Na+ > __ mmol/L
145
165
Which parts of the Small intestines is K absorbed actively?
▪ Active transport in duodenum
| ▪ Passive in jejunum and ileum
166
Mineral that Helps transfer phosphate from ATP to pyruvic acid
K+
167
Hypokalemia
| → Serum K+ < ___ mEq/L
3.5
168
Mineral deficiency that may result with prolonged vomiting, diuretics, kidney disease, metabolic disturbances
K+
169
Ventricular and atrial arrhythmias may manifest with this mineral deficiency
K+
170
Hyperkalemia
| → Serum K+ > ___ mEq/L
5
