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PH 161 > Vitamins & Minerals > Flashcards

Flashcards in Vitamins & Minerals Deck (54)
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0
Q

rapidly converted to its active form, ___in the brain and liver by a specific enzyme, thiamin diphosphotransferase

A

Thiamin pyrophosphate

1
Q

Which vitamin is derived from a substituted pyrimidine and a thiazole coupled by a methylene bridge?

A

B1

2
Q

Thiamine pyrophosphate is necessary as a cofactor for the transketolase catalyzed reactions of the ______ as well as pyruvate dehydrogenase (PDH) and αketoglutarate dehydrogenase catalyzed reactions associated with the _____

A

First blank: pentose phosphate pathway

Second blank: TCA cycle

3
Q

Vit __ is precursor for the coenzymes, flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD)

A

B2

4
Q

FMN is synthesized from riboflavin via the ATP-dependent enzyme ___.

FMN is then converted to FAD via the attachment of AMP (derived from ATP) though the action of ___.

A

First blank:riboflavin kinase

Second blank: FAD pyrophosphorylase

5
Q

Enzymes requiring FMN or FAD as cofactors are called __

A

Flavoproteins

6
Q

succinate dehydrogenase and xanthine oxidase are flavoproteins, true or false?

A

True

7
Q

Vitamin B3 is also known as ___

A

Niacin

8
Q

What are vitB3’s active forms?

A

Nicotinamide adenine dinucleotide
And
Nicotinamid adenine dinucleotide phosphate

9
Q

NAD+
• can be derived from the amino acid ___
• synthesis of niacin from this amino acid requires vitamins __,__ and ___

A

Tryptophan:first blank

B1,B2 and B6:second to 4th blanks

10
Q

Vitamin B5 is also known as ___

A

Pantothenic Acid

11
Q

[SYNTHESIS OF CoA from VIT B5]

Pantothenate is phosphorylated on the hydroxyl group via the action of _____.

The reactive sulfhydryl group is added from ___ via the action of phosphopantothenoylcysteine synthetase.

Through ___ more reactions the molecule is decarboxylated and then the ADP from ATP is added forming the fully functional coenzyme A

A

Pantothenate kinase:first blank
Cysteine:second blank
Three:third blank

12
Q

False about Pantothenate:
A)required for synthesis of coenzyme A, CoA
B)component of the acyl carrier protein (ACP) domain of nucleic acid synthase C)required for the metabolism of carbohydrate via the TCA cycle and all fats and proteins

A

B)component of the acyl carrier protein (ACP) domain of nucleic acid synthase

Fatty acid synthase dapat

13
Q

Vit B6:also known as __

A

Pyridoxine

14
Q

A)Active form of B6

B)active form of B6 achieved via this enzyme

A

A)pyridoxal phosphate

B)pyridoxal kinase

15
Q

Pyridoxal kinase requires this metal for full activity:

A

Zinc

16
Q

Pyridoxal phosphate functions as cofactor for all except
A)enzymes involved in transamination reactions required for amino acid metab
B) glycogen kinase
C)synthesis of the inhibitory neurotransmitter γ-aminobutyric acid (GABA)

A

B)glycogen kinase

Glycogen phosphorylase dapat

17
Q

False about biotin

A)the cofactor required of enzymes that are involved in carboxylation reactions
B)Serves as carriers of activated carbon dioxide
C)Glycoprotein avidin tightly binds with biotin, increasing biotin’s absorption

A

C)Glycoprotein avidin tightly binds with biotin, increasing biotin’s absorption

Restricting biotin’s absorption dapat

18
Q

False about cobalamin

A.composed of a complex tetrapyrrol ring structure (corrin ring) and a cobalt ion in the center

B.is synthesized exclusively by microorganisms and is found in the liver of animals bound to protein as methycobalamin or
5’deoxyadenosylcobalamin

C.must be hydrolyzed from protein in order to be active

D. Also known as Vit B12

A

D. Also known as VitB2

vit B12 dapat

19
Q

Pick the false statement

A.vitamin B12 is bound by intrinsic factor, a protein secreted by parietal cells of the stomach
B.vit B12 is carried to the jejunum where it is absorbed
C. vitamin is transported to the liver in the blood bound to transcobalamin II.

A

B.vit B12 is carried to the jejunum where it is absorbed

It is absorbed in the ileum

20
Q

Which does not require Vit B12?

A)propionyl-CoA conversion succinyl-CoA for oxidation in the TCA cycle. (c/omethylmalonyl-CoA mutase)

B) the conversion of homocysteine to methionine and is catalyzed by methionine synthase

C)glycogenolysis as a cofactor for glycogen phosphorylase

A

C)glycogenolysis as a cofactor for glycogen phosphorylase

This process requires Vitamin B6 and not B12

21
Q

False about Folic Acid

A. Generated via conjugation of glutamic acid residues to pteroic acid.
B. Oxidized within cells (principally the kidney where it is stored) to tetrahydrofolate
C. Conversion to tetrahydrofolate c/o dihydrofolate reductase (DHFR), NADPH-requiring enzyme

A

B. Oxidized within cells (principally the kidney where it is stored) to tetrahydrofolate

Dapat “reduced within cells (principally the liver where it is stored) to tetrahydrofolate”

22
Q

Function of tetrahydrofolate

A

carry and transfer various forms of one carbon units during biosynthetic reactions

23
Q

Pick the false statement

A. Vit C is also known as ascorbic acid
B.Vit C is derived from glucose via the uronic acid pathway
C.ascorbic acid’s active form is ascorbate

A

C.ascorbic acid’s active form is ascorbate

Ascorbic acid’s active form is ascorbic acid itself

24
Q

False about VitC

A)essential to a healthy diet as well as being a highly effective antioxidant B)acts as an electron acceptor for important enzymes
C)with role in synthesis of collagen and carnitine
D)with role in synthesis and catabolism of tyrosine

A

B)acts as an electron acceptor for important enzymes

Electron donor dapat

25
Q

provitamin form of vitamin A

A

Retinal

26
Q

Ingested __ is cleaved in the lumen of the intestine to yield retinal.

Retinal is reduced to retinol by ___, an NADPH requiring enzyme within the intestines.

A

Beta-carotene

Retinaldehyde reductase

27
Q

Retinol is esterified to ___ and delivered to the blood via chylomicrons.

The uptake of chylomicron remnants by the ___ results in delivery of retinol to this organ for storage as a lipid ester within lipocytes.

A

Palmitic acid

Liver

28
Q

Biologically active form of Vit D is 1,25-dihydroxycalciferol or ___. It regulates Ca and P homeostasis.

A

Calcitriol

29
Q

___is released in response to low serum calcium and induces the production of calcitriol.

A

Parathyroid hormone

30
Q

The steroid hormone action of vitamin D occurs via the action of calcitriol binding to a specific intracellular receptor called ___

A

Vitamin D receptor

31
Q

Most vitamin E in U.S. diets is in the form of __

A

Gamma-tocopherol

32
Q

Vitamin E is able to act as free radical scavenger,thus having potent antioxidant properties. True or false?

A

True

33
Q

most abundant tocopherol in tissues outside of the liver

A

Alpha-tocopherol

34
Q

most potent antioxidant forms of the vitamin

A

Gamma-tocopherol and delta-tocopherol

35
Q

[Vit K Forms]

exist naturally as: •
K1 (phylloquinone) in ___
K2 (menaquinone) produced by ___
K3 is synthetic menadione

A

Green vegetables

Intestinal bacteria

36
Q

when administered, vitamin K3 is alkylated to one of the vitamin K1 forms. True or false?

A

False. K2 dapat, hindi K1

37
Q

major function of the K vitamins is in the maintenance of normal levels of the blood clotting proteins, factors II, VII, IX, X and protein C and protein S, which are synthesized in the ____ as inactive precursor proteins

A

Liver

38
Q

Conversion from inactive to active clotting factor requires a posttranslational modification of specific ____ residues (carboxylation). vitK needed as coenzyme

A

Glutamate

39
Q
All of the following are major minerals except:
Calcium 
Magnesium
Sulfur
Iron
A

Iron.

Major minerals:(needed 5mg or more) Calcium,Magnesium,Phosphorus,Sodium,Potassium,Chloride,Sulfur

40
Q
All of the following are minor minerals except
Zinc
Fluoride
Chloride
Iodide
A

Chloride

Minor minerals (needed: less than 5mg) - Iron,Zinc,Copper,Fluoride,Selenium,Iodide,Chromium,Manganese,Molybdenum

41
Q

False about calcium

  1. 2% of total body weight
  2. 99% found in bones
  3. Calcium deficiency makes bones porous
  4. None of the above
A
  1. None of the above
42
Q

2nd Most abundant mineral in the body. Critical in bone formation and rigidity.significant buffer in the blood

A

Phosphorus

43
Q

True or False:Magnesium is a coenzyme in regulating bone and mineral status

A

True

44
Q

False about fluoride
A.prevents cavities in teeth
B.strengthens dentin
C.deficiency symptom: brown stains and cracking of teeth

A

B.strengthens dentin

Enamel,not dentin

45
Q

False about potassium
A.key circulating electrolyte
B.involved in the regulation of ATP-dependent channels (Na+/K+ATPases); primary function is in the transmission of hormones
C. Major mineral siya

A

B.involved in the regulation of ATP-dependent channels (Na+/K+ATPases); primary function is in the transmission of hormones

Hormones? Nah. Nerve impulses dapat

46
Q

False about sulfur
A)has a primary function in amino acid metabolism
B) necessary for the modification of complex carbohydrates present in proteins and lipids;
C)the sulfur comes from the amino acid lysine

A

C)the sulfur comes from the amino acid lysine

Methionine,not lysine

47
Q
Copper has major roles in the following processes except:
A)collagen processing
B)hemoglobin synthesis
C)wound healing
D)transmission of nerve impulses
A

D)transmission of nerve impulses

^ c/o Na,K

48
Q

Iron functions to coordinate the oxygen molecule into ___ of hemoglobin so that it can be transported from the lungs to the tissues

A

Heme

49
Q

Iodine is required for the synthesis of these hormones

A

Thyroid hormones

50
Q

manganese is necessary for the proper function of ____ which is an enzyme required for preventing super oxide anions from damaging cells.

A

Super oxide dismutase

51
Q

Molybdenum: primarily involved as a co-factor in several oxidases such as xanthine oxidase (for ___ catabolism) aldehyde oxidase, and sulfite oxidase.

A

Purine nucleotide

52
Q

Selenium: serves as a modifier of the activity of ___ through its incorporation into the protein in the form of selenocysteine.

A

Glutathione peroxidase

53
Q

Primary role of zinc in biochemical processes

A

Cofactor for enzymes