Description : An enzyme which uses hydrogen acceptor as substrate is (A) Xanthine oxidase (B) Aldehyde oxidase (C) Catalase (D) Tryptophan oxygenase
Last Answer : Answer : C
Description : A molybdenum containing oxidase is (A) Cytochrome oxidase (B) Xanthine oxidase (C) Glucose oxidase (D) L-Amino acid oxidase
Last Answer : Answer : B
Description : Activity of cytochrome oxidase is inhibited by (A) Sulphite (B) Sulphate (C) Arsenite (D) Cyanide
Last Answer : Answer : D
Description : Vitamin K is involved in posttranslational modification of the blood clotting factors by acting as cofactor for the enzyme: (A) Carboxylase (B) Decarboxylase (C) Hydroxylase (D) Oxidase
Last Answer : Answer : A
Description : A drug which prevents uric acid synthesis by inhibiting the enzyme Xanthine oxidase is (A) Aspirin (B) Allopurinal (C) Colchicine (D) Phenyl benzoate
Description : Hypouricaemia can occur in (A) Xanthine oxidase deficiency (B) Psoriasis (C) Leukaemia (D) None of these
Description : Mammals other than higher primates do not suffer from gout because they (A) Lack xanthine oxidase (B) Lack adenosine deaminase (C) Lack purine nucleoside phosphorylase (D) Possess uricase
Description : All of the following statements about allopurinol are true except (A) It is a structural analogue of uric acid (B) It can prevent uric acid stones in the kidneys (C) It increases the urinary excretion of xanthine and hypoxanthine (D) It is a competitive inhibitor of xanthine oxidase
Description : Enzymic deficiency in β-aminoisobutyric aciduria is (A) Adenosine deaminase (B) Xanthine oxidase (C) Orotidylate decarboxylase (D) Transaminase
Description : An autosomal recessive disorder, xanthinuria is due to deficiency of the enzymes: (A) Adenosine deaminase (B) Xanthine oxidase (C) HGPRTase (D) Transaminase
Description : Lesch-Nyhan syndrome, the sex linked recessive disorder is due to the lack of the enzyme: (A) Hypoxanthine-guanine phosphoribosyl transferse (B) Xanthine oxidase (C) Adenine phosphoribosyl transferase (D) Adenosine deaminase
Description : In humans purine are catabolised to uric acid due to lack of the enzyme: (A) Urease (B) Uricase (C) Xanthine oxidase (D) Guanase
Description : Iron is present in all the following except (A) Peroxidase (B) Xanthine oxidase (C) Aconitase (D) Fumarase
Description : A copper containing oxidase is (A) Cytochrome oxidase (B) Flavin mononucleotide (C) Flavin adenine dinucleotide (D) Xanthine oxidase
Description : Schardinger’s enzyme is (A) Lactate dehydrogenase (B) Xanthine dehydrogenase (C) Uric oxidase (D) L amino acid dehydrogenase
Description : Physostigmine is a competitive inhibitor of (A) Xanthine oxidase (B) Cholinesterase (C) Carbonic anhydrase (D) Monoamine oxidase
Description : Insulin degradation of disulfide bond formation is effected by (A) Pyruvate dehydrogenase (B) Xylitol reductase (C) Gutathione reductase (D) Xanthine oxidase
Description : A drug which prevents uric acid synthesis by inhibiting the enzyme xanthine oxidase is (A) Aspirin (B) Allopurinol (C) Colchicine (D) Probenecid
Last Answer : B
Description : Vitamin K is involved in posttranslational modification of the blood clotting factors by acting as cofactor for the enzyme (A) Carboxylase (B) Decarboxylase (C) Hydroxylase (D) Oxidase
Last Answer : (A) Carboxylase
Description : Which of the following statements are true of oxidants? A. In addition to their pathophysiologic roles in inflammation, injury, and infection, oxidants also have physiologic roles. B. Oxidants may ... involved the catalytic production of superoxide anion (O 2 ) by the enzyme xanthine oxidase.
Last Answer : Answer: ABCD DISCUSSION: Oxidants are reactive oxygen metabolites that have both physiologic and pathophysiologic roles. As potent oxidizing agents, oxidants are involved in cytochrome P ... leukocyte infiltration and activation, causing further tissue damage by the release of cytotoxic proteases
Description : Which of the following enzymes is ultimately responsible for the production of prostaglandins associated with inflammatory reactions? (a) Phospholipase (b) Lipoxygenase (c) Cyclooxygenase-I (d) Cyclooxygenase II (e) Xanthine oxidase
Last Answer : Ans: D
Description : Albinism is a congenital disorder resulting from the lack of which enzyme? (a) Tyrosinase (b) Xanthine oxidase (c) Catalase (d) Fructokinase
Last Answer : (a) Tyrosinase
Description : Thioguanine differs from mercaptopurine in that: A. It is not metabolized by xanthine oxidase B. It does not cause hyperuricemia C. Its dose need not be reduced when allopurinol is given concurrently D. Both ‘A’ and ‘C’ are correc
Last Answer : D. Both ‘A’ and ‘C’ are correct
Description : Choose the correct statement about allopurinol: A. It is a purine antimetabolite with antineoplastic activity B. It is a competitive inhibitor of xanthine oxidase C. It is inactive itself ... D. Both allopurinol as well as its metabolite alloxanthine are noncompetitive inhibitors of xanthine oxidase
Last Answer : B. It is a competitive inhibitor of xanthine oxidase
Last Answer : (B) Allopurinol
Description : A cofactor in the conversion of dihydroorotate to orotic acid, catalysed by the enzyme dihydroorotate dehydrogenase is (A) FAD (B) FMN (C) NAD (D) NADP
Description : Zinc is a cofactor for (A) Acid phosphatase (B) Alkaline phosphatase (C) Amylase (D) Lipase
Description : Cobalt may act as cofactor for the enzyme: (A) Glycl-glycine dipeptidase (B) Elastase (C) Polynucleotidases (D) Phosphatase
Description : A cofactor required for the activity of the enzyme ALA dehydratase is (A) Cu (B) Mn (C) Mg (D) Fe
Description : Cofactor (Prosthetic group) is a part of holoenzyme, it is (A) Inorganic part loosely attached (B) Accessory non-protein substance attached firmly (C) Organic part attached loosely (D) None of these
Description : Isocitrate dehydrogenase can use __________ as a cofactor. (A) NAD+ only (B) NADP+ only (C) NAD+ or NADP+ (D) FMN and FAD
Description : Which of the following is not a cofactor? (A) Mg (B) Iron (C) Cu (D) Methylcobalamine
Description : An inorganic ion required for the activity of an enzyme is known as (A) Activator (B) Cofactor (C) Coenzyme (D) None of these
Description : For reduction enzyme HMG-CoA reductase requires cofactor: (A) NADPH (B) NADP (C) NAD (D) FAD
Description : Synthesis of sphingosine requires the cofactor (A) NAD (B) NADP (C) NADPH+ (D) ATP
Description : A cofactor required for the conversion of acetyl-CoA to malonyl-CoA in extramitochondrial fatty acid synthesis is (A) Biotin (B) FMN (C) NAD (D) NADP
Description : The reaction of Kreb’s cycle which does not require cofactor of vitamin B group is (A) Citrate isocitrate (B) α -Ketoglutarate succinate (C) Malate oxaloacetate (D) Succinate fumarate
Description : Cofactor for transamination is (A) Thymine (B) Riboflavin (C) Pyridoxine (D) Niacin
Description : One of the main functions of Vitamin K is the cofactor for (A) Carboxylase for the formation of γ--carboxy glutamate (B) Methylation by S-adenosyl methionine (C) Carboxylation by biotin (D) One carbon transfer by tetra hydrofolate
Description : One of the main functions of Vitamin K is cofactor for (A) Carboxylate for the formation of γ carboxyglutamate (B) Methylation of δ-adenosyl methionine (C) Carboxylation of biotin (D) One carbon transfer by tetrahydrofolate
Description : A cofactor required in oxidative decarboxylation of pyruvate is (A) Lipoate (B) Pantothenic acid (C) Biotin (D) Para aminobenzoic acid
Description : The cofactor or its derivative required for the conversion of acetyl CoA to malonylCoA is (A) FAD (B) ACP (C) NAD+ (D) Biotin
Description : Vitamin K is a cofactor for (A) Gamma carboxylation of glutamic acid residue (B) β-Oxidation of fatty acid (C) Formation of γ-amino butyrate (D) Synthesis of tryptophan
Description : A pathway that requires NADPH as a cofactor is (A) Extramitochondrial folic acid synthesis (B) Ketone body formation (C) Glycogenesis (D) Gluconeogenesis
Description : A pathway that requires NADPH as a cofactor is (A) Fatty acid oxidation (B) Extra mitochondrial denovo fatty acid synthesis (C) Ketone bodies formation (D) Glycogenesis
Description : For the activation of long chain fatty acids the enzyme thiokinase requires the cofactor: (A) Mg++ (B) Ca++ (C) Mn++ (D) K+
Description : An important reaction for the synthesis of amino acid from carbohydrate intermediates is transamination which requires the cofactor: (A) Thiamin (B) Riboflavin (C) Niacin (D) Pyridoxal phosphat
Description : In presence of the following cofactor, pyruvate carboxylase converts pyruvate to oxaloacetate: (A) ATP, Protein and CO2 (B) CO2 and ATP (C) CO2 (D) Protein
Last Answer : A
Description : Nitrosamine can deaminate (A) Cytosine to form uracil (B) Adenine to form xanthine (C) Guanine to form hypoxanthine (D) All of these
Description : An alternate substrate for orotate phosphoribosyl transferase is (A) Allopurinol (B) Xanthine (C) Hypoxanthine (D) Adenine