Description : Adenosine kinase can salvage (A) Adenosine (B) Adenosine and deoxyadenosine (C) Adenosine and guanosine (D) Adenine and adenosine
Last Answer : Answer : B
Description : Phosphorylation of adenosine to AMP is catalysed by (A) Adenosine kinase (B) Deoxycytidine kinase (C) Adenylosuccinase (D) Adenylosuccinate synthetase
Last Answer : Answer : A
Description : An enzyme of pyrimidine nucleotides biosynthesis regulated at the genetic level by apparently coordinate repression and derepression is (A) Carbamoyl phosphate synthetase (B) Dihydroorotate dehydrogenase (C) Thymidine kinase (D) Deoxycytidine kinase
Description : 5’-Terminus of mRNA molecule is capped with (A) Guanosine triphosphate (B) 7-Methylguanosine triphophate (C) Adenosine triphosphate (D) Adenosine diphosphate
Description : Uracil and ribose form (A) Uridine (B) Cytidine (C) Guanosine (D) Adenosine
Description : IN a DNA molecule, the guanosine content is 40%, the adenine content will be (A) 10% (B) 20% (C) 30% (D) 40%
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
Last Answer : Answer : C
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 : 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 : Adrenalin is synthesized from (A) Adenine (B) Adenosine (C) Tyrosine (D) Tryptophan 230 MCQs IN BIOCHEMISTRY
Description : The following cannot be salvaged in human beings: (A) Cytidine (B) Deoxycytidine (C) Cytosine (D) Thymidine
Description : In contrast to Eukaryotic mRNA, prokaryotic mRNA is characterized by (A) Having 7-methyl guanosine triphosphate at the 5’ end (B) Being polycystronic (C) Being only monocystronic (D) Being synthesized with introns
Description : In a DNA molecule the thymine concentration is 30%, the guanosine concentration will be (A) 10% (B) 20% (C) 30% (D) 40%
Description : Photosensitive compound in human eye is made up of (a) opsin and retinol (b) transducin and retinene (c) guanosine and retinol (d) opsin and retinal.
Last Answer : (d) opsin and retinal.
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 : The available PRPP is used preferentially for (A) De novo synthesis of purine nucleotides (B) De novo synthesis of pyrimidine nucleotides (C) Salvage of purine bases (D) Salvage of pyrimidine bases
Description : Nucleotides required for the synthesis of nucleic acids can be obtained from (A) Dietary nucleic acids and nucleotides (B) De novo synthesis (C) Salvage of pre-existing bases and nucleosides (D) De novo synthesis and salvage
Last Answer : Answer : D
Description : Insoinic acid is the biological precursor of (A) Cytosine and Uric acid (B) Adenylve acid and Glucine floc acid (C) Orotic acid and Uridylic acid (D) Adenosine acid Thymidine
Description : A common substrate of HGPRTase, APRTase and PRPP glutamyl amidotransferase is (A) Ribose 5 phosphate (B) Phosphoribosyl pyrophosphate (C) Hypoxanthine (D) Adenosine
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 : The common features of introns include all the following except (A) The base sequence begins with GU (B) The base sequence ends with AG (C) The terminal AG sequence is preceded by a purine rich tract of ten nucleotides (D) An adenosine residue in branch site participates in splicing
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 : Inherited deficiency of adenosine deaminase causes (A) Hyperuricaemia and gout (B) Mental retardation (C) Immunodeficiency (D) Dwarfism
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 : The mushroom poison amanitin is an inhibitor of (A) Protein synthesis (B) mRNA synthesis (C) DNA synthesis (D) Adenosine synthesis
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 : 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 : cAMD is destroyed by (A) Adenylate cyclase (B) Phosphodiesterase (C) Synthetase phosphatase (D) Synthetase kinase
Description : Activated phospholipase C acts on (A) Phosphatidyl inositol-4, 5-biphosphate (B) Inositol-1, 4, 5-triphosphate (C) Protein kinase C (D) Pl-3 kinase
Description : The protein IRS-1 is phosphorylated by (A) Protein kinase A (B) Protein kinase C (C) Tyrosine kinase activity of insulin receptor (D) Tyrosine kinase activity of IGF-1 receptor
Description : Activation of IRS-1, PI-3 kinase and GRB2 is brought about by (A) Glucagon (B) Insulin (C) Prolactin (D) IGF-2
Description : Vasoconstrictor effect of ADH is mediated by (A) cAMP (B) cGMP (C) Protein kinase C (D) Angiotensin II
Description : All the following statements about epidermal growth factor are true except (A) It is a protein (B) It possess quaternary structure (C) Its receptor is made up of a single polypeptide chain (D) Its receptor possesses tyrosine kinase domain
Description : Binding of insulin to its receptor activates (A) Adenylate cyclase (B) Guanylate cyclase (C) Phospholipase C (D) Tyrosine kinase
Description : In the insulin receptor, tyrosine kinase domain is present in (A) α-Subunits (B) β-Subunits (C) γ-Subunits (D) δ-Subunits
Description : Protein kinase C is activated by (A) Cyclic AMP (B) Cyclic GMP (C) Diacyl glycerol (D) Inositol triphosphate
Description : Tyrosine kinase activity is present in (A) Acetylcholine receptor (B) PDGF receptor (C) ADH receptor (D) All of these
Description : Tyrosine kinase activity is present in (A) α-Adrenergic receptors (B) β-Adrenergic receptors (C) Cholinergic receptors (D) Insulin receptors
Description : Insulin decreases the activity of (A) cAMP dependent protein kinase (B) HMG CoA-reductas (C) Phosphodiesterase (D) Acetyl CoA-carboxylase
Description : Insulin increases the activity of (A) Pyruvate kinase (B) Phosphorylase (C) Triacylglycerol kinase (D) Fructose 2, 6-bisphosphatase
Description : In conversion of lactic acid to glucose, three reactions of glycolytic pathway are circumvented, which of the following enzymes do not participate? (A) Pyruvate carboxylase (B) Phosphoenol pyruvate carboxy kinase (C) Pyruvate kinase (D) Glucose-6-phosphatase
Description : This catalyzes formation of CoA derivatives from fatty acid, CoA and ATP: (A) Acyl CoA dehydrogenase (B) Enoyl hydrase (C) β-OH acyl CoA dehydrogenase (D) Thio kinase
Description : Glucose-6-phosphatase and PEP carboxy kinase are regulated by (A) Covalent modification (B) Allosteric regulation (C) Induction and repression (D) All of these
Description : A gluconeogenic enzyme among the following is (A) Phosphofructokinase (B) Pyruvate kinase (C) Phosphoenol pyruvate carboxykinase (D) Glucokinase
Description : Cyclic AMP binds to (A) Catalytic subunits of protein kinase (B) Regulatory subunits of protein kinase (C) Catalytic subunits of phosphorylase kinase (D) Regulatory subunits of phosphorylase kinase
Description : A molecule of phosphorylase kinase is made up of (A) 4 subunits (B) 8 subunits (C) 12 subunits (D) 16 subunits
Description : Which of the following enzymes incorporates inorganic phosphate into the substrate? (A) Phosphoglycerate kinase (B) Glyceraldehyde-3-phosphate dehydrogenase (C) Pyruvate kinase (D) Enolase
Description : Creatine kinase is present in all of the following except (A) Liver (B) Myocardium (C) Muscles (D) Brain
Description : The first enzyme found to have isoenzymes was (A) Alkaline Phosphatase (B) Lactate dehydrogenase (C) Acid Phosphatase (D) Creatine kinase