rapidly converted to its active form, ___in the brain and liver by a specific enzyme, thiamin diphosphotransferase
Thiamin pyrophosphate
Which vitamin is derived from a substituted pyrimidine and a thiazole coupled by a methylene bridge?
B1
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 _____
First blank: pentose phosphate pathway
Second blank: TCA cycle
Vit __ is precursor for the coenzymes, flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD)
B2
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 ___.
First blank:riboflavin kinase
Second blank: FAD pyrophosphorylase
Enzymes requiring FMN or FAD as cofactors are called __
Flavoproteins
succinate dehydrogenase and xanthine oxidase are flavoproteins, true or false?
True
Vitamin B3 is also known as ___
Niacin
What are vitB3’s active forms?
Nicotinamide adenine dinucleotide
And
Nicotinamid adenine dinucleotide phosphate
NAD+
• can be derived from the amino acid ___
• synthesis of niacin from this amino acid requires vitamins __,__ and ___
Tryptophan:first blank
B1,B2 and B6:second to 4th blanks
Vitamin B5 is also known as ___
Pantothenic Acid
[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
Pantothenate kinase:first blank
Cysteine:second blank
Three:third blank
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
B)component of the acyl carrier protein (ACP) domain of nucleic acid synthase
Fatty acid synthase dapat
Vit B6:also known as __
Pyridoxine
A)Active form of B6
B)active form of B6 achieved via this enzyme
A)pyridoxal phosphate
B)pyridoxal kinase
Pyridoxal kinase requires this metal for full activity:
Zinc
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)
B)glycogen kinase
Glycogen phosphorylase dapat
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
C)Glycoprotein avidin tightly binds with biotin, increasing biotin’s absorption
Restricting biotin’s absorption dapat
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
D. Also known as VitB2
vit B12 dapat
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.
B.vit B12 is carried to the jejunum where it is absorbed
It is absorbed in the ileum
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
C)glycogenolysis as a cofactor for glycogen phosphorylase
This process requires Vitamin B6 and not B12
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
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”
Function of tetrahydrofolate
carry and transfer various forms of one carbon units during biosynthetic reactions
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
C.ascorbic acid’s active form is ascorbate
Ascorbic acid’s active form is ascorbic acid itself
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
B)acts as an electron acceptor for important enzymes
Electron donor dapat
provitamin form of vitamin A
Retinal
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.
Beta-carotene
Retinaldehyde reductase
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.
Palmitic acid
Liver
Biologically active form of Vit D is 1,25-dihydroxycalciferol or ___. It regulates Ca and P homeostasis.
Calcitriol
___is released in response to low serum calcium and induces the production of calcitriol.
Parathyroid hormone
The steroid hormone action of vitamin D occurs via the action of calcitriol binding to a specific intracellular receptor called ___
Vitamin D receptor
Most vitamin E in U.S. diets is in the form of __
Gamma-tocopherol
Vitamin E is able to act as free radical scavenger,thus having potent antioxidant properties. True or false?
True
most abundant tocopherol in tissues outside of the liver
Alpha-tocopherol
most potent antioxidant forms of the vitamin
Gamma-tocopherol and delta-tocopherol
[Vit K Forms]
exist naturally as: •
K1 (phylloquinone) in ___
K2 (menaquinone) produced by ___
K3 is synthetic menadione
Green vegetables
Intestinal bacteria
when administered, vitamin K3 is alkylated to one of the vitamin K1 forms. True or false?
False. K2 dapat, hindi K1
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
Liver
Conversion from inactive to active clotting factor requires a posttranslational modification of specific ____ residues (carboxylation). vitK needed as coenzyme
Glutamate
All of the following are major minerals except: Calcium Magnesium Sulfur Iron
Iron.
Major minerals:(needed 5mg or more) Calcium,Magnesium,Phosphorus,Sodium,Potassium,Chloride,Sulfur
All of the following are minor minerals except Zinc Fluoride Chloride Iodide
Chloride
Minor minerals (needed: less than 5mg) - Iron,Zinc,Copper,Fluoride,Selenium,Iodide,Chromium,Manganese,Molybdenum
False about calcium
- 2% of total body weight
- 99% found in bones
- Calcium deficiency makes bones porous
- None of the above
- None of the above
2nd Most abundant mineral in the body. Critical in bone formation and rigidity.significant buffer in the blood
Phosphorus
True or False:Magnesium is a coenzyme in regulating bone and mineral status
True
False about fluoride
A.prevents cavities in teeth
B.strengthens dentin
C.deficiency symptom: brown stains and cracking of teeth
B.strengthens dentin
Enamel,not dentin
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
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
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
C)the sulfur comes from the amino acid lysine
Methionine,not lysine
Copper has major roles in the following processes except: A)collagen processing B)hemoglobin synthesis C)wound healing D)transmission of nerve impulses
D)transmission of nerve impulses
^ c/o Na,K
Iron functions to coordinate the oxygen molecule into ___ of hemoglobin so that it can be transported from the lungs to the tissues
Heme
Iodine is required for the synthesis of these hormones
Thyroid hormones
manganese is necessary for the proper function of ____ which is an enzyme required for preventing super oxide anions from damaging cells.
Super oxide dismutase
Molybdenum: primarily involved as a co-factor in several oxidases such as xanthine oxidase (for ___ catabolism) aldehyde oxidase, and sulfite oxidase.
Purine nucleotide
Selenium: serves as a modifier of the activity of ___ through its incorporation into the protein in the form of selenocysteine.
Glutathione peroxidase
Primary role of zinc in biochemical processes
Cofactor for enzymes