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
Last Answer : Answer : C
Description : Pyruvate carboxylase is regulated by (A) Induction (B) Repression (C) Allosteric regulation(D) All of these
Last Answer : D
Description : Regulation of haem synthesis occurs by (A) Covalent modification (B) Repression - derepression (C) Induction (D) Allosteric regulation
Last Answer : Answer : B
Description : Acetyl CoA carboxylase regulates fatty acid synthesis by which of the following mechanism? (A) Allosteric regulation (B) Covalent modification (C) Induction and repression (D) All of these
Last Answer : Answer : D
Description : An allosteric inhibitor of pyruvate dehydrogenase is (A) Acetyl CoA (B) ATP (C) NADH (D) Pyruvate
Last Answer : Answer : A
Description : Which one of the following regulatory actions involves a reversible covalent modification of the enzyme? (A) Phosphorylation of ser-OH on the enzyme (B) Allosteric modulation (C) Competitive inhibition (D) Non-competitive inhibition
Description : Which of the following regulatory reactions involves a reversible covalent modification of an enzyme? (A) Phosphorylation of serine OH on the enzyme (B) Allosteric modulation (C) Competitive inhibition (D) Non-competitive inhibition
Description : An enzyme of pyrimidine nucleotide biosynthesis sensitive to allosteric regulation is (A) Aspartate transcarbamoylase (B) Dihydroorotase (C) Dihydroorotate dehydrogenase (D) Orotidylic acid decarboxylase
Description : Regulation of some enzymes by covalent modification involves addition or removal of (A) Acetate (B) Sulphate (C) Phosphate (D) Coenzyme
Description : Formation of acetyl CoA from pyruvate for de novo synthesis of fatty acids requires (A) Pyruvate dehydrogenase complex (B) Citrate synthetase (C) ATP citrate lyase (D) All of these
Description : A flavoprotein in pyruvate dehydrogenase complex is (A) Pyruvate dehydrogenase (B) Didrolipoyl acetyl transferase (C) Dihydrolipoyl dehydrogenase (D) None of these ENZYMES 161
Description : Pyruvate dehydrogenase complex is located in (A) Cytosol (B) Lysosomes (C) Mitochondria (D) Endoplasmic reticulum
Description : Pyruvate dehydrogenase a multienzyme complex is required for the production of (A) Acetyl-CoA (B) Lactate (C) Phosphoenolpyruvate (D) Enolpyruvate
Description : Acetyl CoA required for extra mitochondrial fatty acid synthesis is produced by (A) Pyruvate dehydrogenase complex (B) Citrate lyase (C) Thiolase (D) Carnitine-acyl transferase
Description : Pyruvate dehydrogenase complex and α-ketoglutarate dehydrogenase complex require the following for their oxidative decarboxylation: (A) COASH and Lipoic acid (B) NAD+ and FAD (C) COASH and TPP (D) COASH, TPP,NAD+,FAD, Lipoate
Description : In gluconeogensis, an allosteric activator required in the synthesis of oxaloacetate from bicarbonate and pyruvate, which is catalysed by the enzyme pyruvate carboxylase is (A) Acetyl CoA (B) Succinate (C) Isocitrate (D) Citrate
Description : Which of the following compound is a positive allosteric modifier of the enzyme pyruvate carboxylase? (A) Biotin (B) Acetyl CoA (C) Oxaloacetate (D) ATP
Last Answer : A
Description : GMP is an allosteric inhibitor of all the following except (A) PRPP synthetase (B) PRPP glutamyl amido synthetase (C) IMP dehydrogenase (D) Adenylosuccinate synthetase
Description : An allosteric inhibitor of IMP dehydrogenase is (A) AMP (B) ADP (C) GMP (D) GDP
Description : In the pathway of de novo synthesis of purine nucleotides, all the following are allosteric enzymes except (A) PRPP glutamyl amido transferase (B) Adenylosuccinate synthetase (C) IMP dehydrogenase (D) Adenylosuccinase
Description : An example of feedback inhibition is (A) Allosteric inhibition of hexokinase by glucose6-phosphate (B) Cyanide action on cytochrome (C) Sulpha drug on folic acid synthesizer bacteria (D) Reaction between succinic dehydrogenase and succinic acid
Description : Which of the following is an allosteric enzyme? (A) Phosphohexose isomerase (B) Phosphotriose isomerase (C) Lactate dehydrogenase (D) Phosphofructokinase
Description : All of the following are allosteric enzymes except (A) Citrate synthetase (B) a-Ketoglutarate dehdrogenase (C) Succinate thiokinase (D) Succinate dehydrogenase
Description : The rate of citric acid cycle is controlled by the allosteric enzyme: (A) Aconitase (B) Fumarase (C) Fumarase (D) Malate dehydrogenase
Description : Allosteric inhibitor of glutamate dehydrogenase is (A) ATP (B) ADP (C) AMP (D) GMP
Description : An allosteric enzyme responsible for controlling the rate of T.C.A cycle is (A) Malate dehydrogenase (B) Isocitrate dehydrogenase (C) Fumarase (D) Aconitase
Last Answer : B
Description : Lipoic acid is a conenzyme for (A) Pyruvate dehydrogenase (B) α-Ketoglutarate dehydrogenae (C) Both (A) and (B) (D) None of these
Description : The glycolysis is regulated by (A) Hexokinase (B) Phosphofructokinase (C) Pyruvate kinase (D) All of these
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 : A mitochondrial marker enzyme is (A) Aldolase (B) Amylase (C) Succinic dehydrogenase (D) Pyruvate dehydrogenase ENZYMES 175
Description : Pyruvate dehydrogenase contains all except (A) Biotin (B) NAD (C) FAD (D) CoA
Description : Pyruvate dehydrogenase is a/an (A) Isomerase (B) Lyase (C) Ligase (D) Oxido reductase
Description : Thiamine is essential for (A) Pyruvate dehydrogenase (B) Isocitrate dehydrogenase (C) Succinate dehydrogenase (D) Acetyl CoA synthetase ENZYMES 165
Description : All the following are coenzymes except (A) Ubiquinone (B) CoA (C) Pyruvate dehydrogenase (D) Lipoic acid
Description : Coenzymes derived from the vitamin shown below are required by which of the following enzymes? (A) Lactate dehydrogenase (B) Glutamate dehydrogenase (C) Pyruvate dehydrogenase (D) Malate dehydrogenase
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 : Conversion of pyruvate into acetyl CoA is catalysed by (A) Pyruvate dehydrogenase (B) Didrolipoyl acetyl transferase (C) Dihydrolipoyl dehydrogenase (D) All the 3 acting in concert
Description : Biotin is a coenzyme for (A) Pyruvate dehydrogenase (B) Pyruvate carboxylase (C) PEP carboxykinase (D) Glutamate pyruvate transminase
Description : The principal action of insulin in adipose tissue is to inhibit the activity of the (A) Hormone sensitive lipoprotein lipase (B) Glycerol phosphate acyltransferase (C) Acetyl-CoA carboxylase (D) Pyruvate dehydrogenase
Description : Acetyl-CoA is the principal building block of fatty acids. It is produced within the mitochondria and does not diffuse readily into cytosol. The availability of acetyl CoA involves (A) Carnitine acyl transferase (B) Pyruvate dehydrogenase (C) Citrate lyase (D) Thiolase
Description : Acute hemolytic anemia in person’s sensitive to the Fava beans is due to the deficiency of the enzyme: (A) Pyruvate dehydrogenase (B) G-6-PD (C) Aconitase (D) Transketolase
Description : Insulin has no effect on the activity of the enzyme: (A) Glycogen synthetase (B) Fructokinase (C) Pyruvate kinase (D) Pyruvate dehydrogenase
Description : The initial step of the citric acid cycle is (A) Conversion of pyruvate to acetyl-CoA (B) Condensation of acetyl-CoA with oxaloacetate (C) Conversion of citrate to isocitrate (D) Formation of α -ketoglutarate catalysed by isocitrate dehydrogenase
Description : Pyruvate dehydrogenase activity is inhibited by (A) Mercury (B) Zinc (C) Calcium (D) Sodium
Description : Dietary deficiency of thiamin inhibits the activity of the enzyme: (A) Pyruvate kinase (B) Pyruvate dehydrogenase (C) Phosphofructokinase (D) Enolase
Description : Enzymes leading to the high energy phosphorylation of substrates during glycolysis include which of the following? (A) Phosphoglycerate kinase (B) Enolase (C) Pyruvate Kinase (D) Glyceraldehyde-3-phosphate dehydrogenase
Description : In the glycolytic pathway, enolpyruvate is converted to ketopyruvate by (A) Pyruvate kinase (B) Phosphoenolpyruvate (C) Pyruvate dehydrogenase (D) Spontaneously
Description : In glycolytic pathway, iodacetate inhibits the activity of the enzyme: (A) Phosphotriose isomerase (B) Glyceraldehyde-3-phosphate dehydrogenase (C) Pyruvate kinase (D) Phosphofructokinase
Description : NADPH is produced when this enzyme acts (A) Pyruvate dehydrogenase (B) Malic enzyme (C) Succinate dehydrogenase (D) Malate dehydrogenase
Description : Insulin degradation of disulfide bond formation is effected by (A) Pyruvate dehydrogenase (B) Xylitol reductase (C) Gutathione reductase (D) Xanthine oxidase