Description : All the following statements about primary gout are true except (A) Its inheritance is X-linked recessive (B) It can be due to increased activity of PRPP synthetase (C) It can be ... activity of hypoxanthine guanine phosphoribosyl transferase (D) De novo synthesis of purines is increased in it
Last Answer : Answer : C
Description : An autosomal recessive disorder, xanthinuria is due to deficiency of the enzymes: (A) Adenosine deaminase (B) Xanthine oxidase (C) HGPRTase (D) Transaminase
Last Answer : Answer : B
Description : Lesch-Nyhan syndrome, the sex linked, recessive absence of HGPRTase, may lead to (A) Compulsive self destructive behaviour with elevated levels of urate in serum (B) Hypouricemia due to liver damage (C) Failure to thrive and megaloblastic anemia (D) Protein intolerance and hepatic encephalopathy
Last Answer : Answer : A
Description : The enzyme required for salvage of free purine bases is (A) Adenine phosphoribosyl transferase (B) Hypoxanthine guanine phosphoribosyl transferase (C) Both (A) and (B) (D) None of these
Description : Trials for gene therapy in human beings were first carried out, with considerable success, in a genetic disease called (A) Cystic fibrosis (B) Thalassemia (C) Adenosine deaminase deficiency (D) Lesch-Nyhan syndrome
Description : An alternate substrate for orotate phosphoribosyl transferase is (A) Allopurinol (B) Xanthine (C) Hypoxanthine (D) Adenine
Last Answer : Answer : D
Description : Salvage of purine bases is regulated by (A) Adenosine phosphoribosyl transferase (B) Hypoxanthine guanine phosphoribosyl transferase (C) Availability of PRPP (D) None of these
Description : Complete absence of hypoxanthine guanine phospharibosyl transferase causes (A) Primary gout (B) Immunodeficiency (C) Uric acid stones (D) Lesh-Nyhan syndrome
Description : Conversion of inosine monophosphate to xanthine monophosphate is catalysed by (A) IMP dehydrogenase (B) Formyl transferase (C) Xanthine-guanine phosphoribosyl transferase (D) Adenine phosphoribosyl transferase
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 are true about lesch-nyhan syndrome except (A) Produces self-mutilation (B) Genetic deficiency of the enzyme (C) Elevated levels of uric acid in blood (D) Inheritance is autosomal recessive
Description : In inherited deficiency of hypoxanthine guanine phosphoribosyl transferase (A) De novo synthesis of purine nucleotides is decreased (B) Salvage of purines is decreased (C) Salvage of purines is increased (D) Synthesis of uric acid is decreased
Description : Enzymic deficiency in β-aminoisobutyric aciduria is (A) Adenosine deaminase (B) Xanthine oxidase (C) Orotidylate decarboxylase (D) Transaminase
Description : Nitrosamine can deaminate (A) Cytosine to form uracil (B) Adenine to form xanthine (C) Guanine to form hypoxanthine (D) All of these
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 : A common substrate of HGPRTase, APRTase and PRPP glutamyl amidotransferase is (A) Ribose 5 phosphate (B) Phosphoribosyl pyrophosphate (C) Hypoxanthine (D) Adenosine
Description : Pick out the correct statements. (1) Haemophilia is a sex-linked recessive disease. (2) Down's syndrome is due to aneuploidy. (3) Phenylketonuria is an autosomal recessive gene disorder. (4) Sickle cell anaemia is an X- ... are correct. (c) (1) and (4) are correct. (d) (2) and (4) are correct.
Last Answer : (b) (1), (2) and (3) are correct.
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 : 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 : 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 : Lesch-Nyhan syndrome?
Last Answer : DefinitionLesch-Nyhan syndrome is an inheritable disorder that affects how the body builds and breaks down purines. Purines are a normal part of human tissue and help make up the body's genetic blueprint. ... to develop gout-like swelling in some of their joints. In some cases, kidney and bl
Description : Hybridoma cells are selected by culturing them in a medium containing (A) Adenine, guanine, cytosine and thymine (B) Adenine, guanine, cytosine and uracil (C) Hypoxanthine, aminopterin and thymine (D) Hypoxanthine, aminopterin and thymidine
Description : Free purine bases which can be salvaged are (A) Adenine and guanine (B) Adenine and hypoxanthine (C) Guanine and hypoxanthine (D) Adenine, guanine and hypoxanthine
Description : A copper containing oxidase is (A) Cytochrome oxidase (B) Flavin mononucleotide (C) Flavin adenine dinucleotide (D) Xanthine oxidase
Description : The enzyme common to catabolism of all the purines is (A) Adenosine deaminase (B) Purine nucleoside phosphorylase (C) Guanase (D) None of these
Description : Orotic aciduria type II reflects the deficiency of the enzyme: (A) Orotate phosphoribosyl transferase (B) Orotidylate decarboxylase (C) Dihydroorotase (D) Dihydroorotate dehydrogenase
Description : Methotrexate blocks the synthesis of thymidine monophosphate by inhibiting the activity of the enzyme: (A) Dihydrofolate reductase (B) Orotate phosphoribosyl transferase (C) Ribonucleotide reductase (D) Dihydroorotase
Description : LCAT is (A) Lactose choline alamine transferse (B) Lecithin cholesterol acyl transferase (C) Lecithin carnitine acyl transferase (D) Lanoleate carbamoyl acyl transferase
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 : Schardinger’s enzyme is (A) Lactate dehydrogenase (B) Xanthine dehydrogenase (C) Uric oxidase (D) L amino acid dehydrogenase
Description : An enzyme which uses hydrogen acceptor as substrate is (A) Xanthine oxidase (B) Aldehyde oxidase (C) Catalase (D) Tryptophan oxygenase
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 : The genetic defect-adenosine deaminase (ADA) deficiency may be cured permanently by (a) administering adenosine deaminase activators (b) introducing bone marrow cells producing ADA into ... replacement therapy (d) periodic infusion of genetically engineered lymphocytes having functional ADA cDNA
Last Answer : (b) introducing bone marrow cells producing ADA into cells at early embryonic stages
Description : A deficiency of copper effects the formation of normal collagen by reducing the activity of which of the following enzyme? (A) Prolyl hydroxylase (B) Lysyl oxidase (C) Lysyl hydroxylase (D) Glucosyl transferase
Description : The end product of purine catabolism in man is (A) Inosine (B) Hypoxanthine (C) Xanthine (D) Uric acid
Description : The nitrogenous base present in the RNA molecule is (A) Thymine (B) Uracil (C) Xanthine (D) Hypoxanthine
Last Answer : (B) Allopurinol
Description : $ Haemophilia is a sex linked disease ! Haemophilia is due to a recessive gene.
Last Answer : $ Haemophilia is a sex linked disease ! Haemophilia is due to a recessive gene. A. If both As and R are ... R is wrong D. If both As and R are wrong.
Description : Inherited deficiency of adenosine deaminase causes (A) Hyperuricaemia and gout (B) Mental retardation (C) Immunodeficiency (D) Dwarfism
Description : Increased urinary excretion of orotic acid can occur in deficiency of (A) Orotate phosphoribosyl transferase (B) OMP decarboxylase (C) Mitochondrial ornithine transcarbamoylase (D) Any of the above
Description : The first reaction unique to purine nucleotide synthesis is catalysed by (A) PRPP synthetase (B) PRPP glutamyl amido transferase (C) Phosphoribosyl glycinamide synthetase (D) Formyl transferase
Description : Orotic aciduria type I reflects the deficiency of enzymes: (A) Orotate phosphoribosyl transferase and orotidylate decarboxylase (B) Dihydroorotate dehydrogenase (C) Dihydroorotase (D) Carbamoyl phosphate synthetase
Description : Epinephrine is rapidly metabolized by (A) Monoamine oxidase (B) Deaminase (C) Transminase (D) Decarboxylase
Description : The correct sequence of the reactions of catabolism of adenosine to uric acid is (A) Adenosine→hypoxanthine→xanthine→uric acid (B) Adenosine→xanthine→inosine→uric acid (C) Adenosine→inosine→hypoxanthine→ xanthine uric acid (D) Adenosine→xanthine→inosine→hypoxanthine uric acid
Description : Allopurinol lowers the plasma concentration of: A. Hypoxanthine B. Xanthine C. Uric acid D. All of the above
Last Answer : C. Uric acid
Description : Hypouricaemia can occur in (A) Xanthine oxidase deficiency (B) Psoriasis (C) Leukaemia (D) None of these
Description : Molybdenum is a cofactor for (A) Xanthine oxidase (B) Aldehyde oxidase (C) Sulphite oxidase (D) All of these
Description : Iron is present in all the following except (A) Peroxidase (B) Xanthine oxidase (C) Aconitase (D) Fumarase
Description : A molybdenum containing oxidase is (A) Cytochrome oxidase (B) Xanthine oxidase (C) Glucose oxidase (D) L-Amino acid oxidase
Description : Physostigmine is a competitive inhibitor of (A) Xanthine oxidase (B) Cholinesterase (C) Carbonic anhydrase (D) Monoamine oxidase