Description : In humans end product of purine catabolism is (A) Uric acid (B) Urea (C) Allantoin (D) Xanthine
Last Answer : Answer : A
Description : Uric acid is the end product of purine as well as protein catabolism in (A) Man (B) Fish (C) Birds (D) None of these
Last Answer : Answer : C
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 : 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 : 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
Last Answer : Answer : B
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 : In humans purine are catabolised to uric acid due to lack of the enzyme: (A) Urease (B) Uricase (C) Xanthine oxidase (D) Guanase
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 : In humans, the principal metabolic product of pyrimidines is (A) Uric acid (B) Allantoin (C) Hypoxanthine (D) β-alanine
Last Answer : Answer : D
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
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 : The nitrogenous base present in the RNA molecule is (A) Thymine (B) Uracil (C) Xanthine (D) Hypoxanthine
Description : Complete absence of hypoxanthine guanine phospharibosyl transferase causes (A) Primary gout (B) Immunodeficiency (C) Uric acid stones (D) Lesh-Nyhan syndrome
Description : β -Aminoisobytyrate is formed from catabolism of (A) Cytosine (B) Uracil (C) Thymine (D) Xanthine
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 : 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 : 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 : Which pathway is correct for catabolism of purines to form uric acid? (A) Guanylate→Adenylate→Xanthine→hypoxanthine→Uric acid (B) Guanylate→inosinate→Xanthine→hypoxanthine→Uric acid (C) Adenylate→Inosinate→Xanthine hypoxanthine→Uric acid (D) Adenylate→Inosinate→hypoxanthine Xanthine→Uric acid
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 : Xanthuric acid is an abnormal metabolite of (A) Xanthine (B) Uric acid (C) Tyrosine (D) Tryptophan
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 : 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 : The enzyme common to catabolism of all the purines is (A) Adenosine deaminase (B) Purine nucleoside phosphorylase (C) Guanase (D) None of these
Description : Gout is a metabolic disorder of catabolism of (A) Pyrimidine (B) Purine (C) Alanine (D) Phenylalanine
Description : A 73 year old male presented with an acute attack of gout in his left knee. What is the most likely underlying metabolic cause? 1) decreased renal excretion of uric acid 2) endogenous overproduction of uric acid 3) excessive dietary purine intake 4) lactic acidosis 5) starvation
Last Answer : Answers-1 The aetiology of gout can broadly be divided into cases where there is underexcretion of urate via the kidney (90%) or endogenous overproduction of uric acid (10%) although in practical ... diuretic use. Excessive dietary intake of purines is unlikely to be the main cause in this case.
Last Answer : (B) Allopurinol
Description : The major end product of protein nitrogen metabolism in man is (A) Glycine (B) Uric acid (C) Urea (D) NH3
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
Description : Assertion: Uric acid is produced by the metabolism of purine and pyrimidine. Reason: Uric acid has high toxicity and is soluble in water.
Last Answer : Assertion: Uric acid is produced by the metabolism of purine and pyrimidine. Reason: Uric acid has ... D. If both Assertion and Reason are false
Description : Uric acid is the catabolic end product of (A) Porphyrine (B) Purines (C) Pyrimidines (D) Pyridoxine
Description : The end product of amino acid nitrogen metabolism in uricotelic organisms (reptiles and birds) is (A) Bilirubin (B) Urea (C) Uric acid (D) Biliverdin
Description : All following are naturally occurring nucleotides except (A) Cyclic AMP (B) ATP (C) DNA (D) Inosine monophosphate
Description : Inosine monophophate is an intermediate during the de novo synthesis of (A) AMP and GMP (B) CMP and UMP (C) CMP and TMP (D) All of these
Description : In humans, the principal break down product of purines is (A) NH3 (B) Allantin (C) Alanine (D) Uric acid
Description : The major catabolic product of pyrimidines in human is (A) β-Alanine (B) Urea (C) Uric acid (D) Guanine
Description : An enzyme involved in catabolism of catecholamines is (A) Dopa decarboxylase (B) Aromatic amino acid decarboxylase (C) Monoamine oxidase (D) Catechol oxidas
Description : A molybdenum containing oxidase is (A) Cytochrome oxidase (B) Xanthine oxidase (C) Glucose oxidase (D) L-Amino acid oxidase
Description : A common substrate of HGPRTase, APRTase and PRPP glutamyl amidotransferase is (A) Ribose 5 phosphate (B) Phosphoribosyl pyrophosphate (C) Hypoxanthine (D) Adenosine
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 : 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
Description : Folic acid or folate consists of the (A) Base pteridine, p-amino benzoic acid and asparate (B) Base purine, p-amino benzoic acid and glutamate (C) Base pteridine, p-amino benzoic acid and glutamate (D) Base purine, p-hydroxy benzoic acid and glutamate
Description : Catabolism of thymidylate gives (A) α-alanine (B) β-alanine (C) α-aminoisobutyrate (D) β-aminoisobutyrate
Description : Hypouricaemia can occur in (A) Xanthine oxidase deficiency (B) Psoriasis (C) Leukaemia (D) None of these
Description : The following coenzyme is required for catabolism of pyrimidine bases: (A) NADH (B) NADPH (C) FADH2 (D) None of these
Description : β -Alanine is formed from catabolism of (A) Thymine (B) Thymine and cytosine (C) Thymine and uracil (D) Cytosine and uracil
Description : Free ammonia is liberated during the catabolism of (A) Cytosine (B) Uracil (C) Thymine (D) All of these
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