Description : The rate of citric acid cycle is controlled by the allosteric enzyme: (A) Aconitase (B) Fumarase (C) Fumarase (D) Malate dehydrogenase
Last Answer : Answer : C
Description : In TCA cycle, oxalosuccinate is converted to α-ketoglutarate by the enzyme: (A) Fumarase (B) Isocitrate dehydrogenase (C) Aconitase (D) Succinase
Last Answer : Answer : B
Description : Substrate level phosphorylation in TCA cycle is in step: (A) Isocitrate dehydrogenase (B) Malate dehydrogenase (C) Aconitase (D) Succinate thiokinase
Last Answer : D
Description : Among citric acid cycle enzymes, a flavoprotein is (A) Malate (B) Fumarase (C) Succinate dehrogenase (D) Isocitrate dehrogenase
Description : An enzyme of the citric acid cycle also found outside the mitochondria is (A) Isocitrate dehydrogenase (B) Citrate synthetase (C) α-Ketoglutarate dehydrogenase (D) Malate dehydrogenase
Description : Calcium is required for the activation of the enzyme: (A) Isocitrate dehydrogenase (B) Fumarase (C) Succinate thiokinase (D) ATPase
Last Answer : Answer : D
Description : All enzymes of TCA cycle are located in the mitochondrial matrix except one which is located in inner mitochondrial membranes in eukaryotes and in cytosol in prokaryotes. This enzyme is (a) isocitrate dehydrogenase (b) malate dehydrogenase (c) succinate dehydrogenase (d) lactate dehydrogenase.
Last Answer : (c) succinate dehydrogenase
Description : With the exception of glycine all amino acids found in protein are (A) Isocitrate dehydrogenase (B) Fumarase (C) Succinate thiokinase (D) ATPase
Description : Malonate is an inhibitor of (A) Malate dehydrogenase (B) α-Ketoglutarate dehydrogenase (C) Succinate dehydrogenase (D) Isocitrate dehydrogenase
Description : In the TCA cycle, at which of the following enzyme-catalyzed steps, incorporation of elements of water into an intermediate of the cycle takes place : (A) Citrate synthase (B) Aconitase (C) Maleate dehydrogenase (D) Succinyl Co-A synthase
Last Answer : (C) Maleate dehydrogenase
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
Last Answer : Answer : A
Description : Fluoroacetate inhibits the reaction of citric acid cycle: (A) Isocitrate α-Ketoglutarate (B) Fumarate α-Malate (C) Citrate α-cis-aconitate (D) Succinate α-fumarate
Description : The example of generation of a high energy phosphate at the substrate level in the citric acid cycle is the reaction: (A) Isocitrate α-Ketoglutarate (B) Succinate α-fumarate (C) Malate α-oxaloacetate (D) Succinyl CoA α-Succinate
Description : The substance which may be considered to play a catalytic role in citric acid cycle is (A) Oxaloacetate (B) Isocitrate (C) Malate (D) Fumarate
Description : Iron is present in all the following except (A) Peroxidase (B) Xanthine oxidase (C) Aconitase (D) Fumarase
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 : 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 : In citric acid cycle, GDP is phosphorylated by (A) Succinate dehydrogenase (B) Aconitase (C) Succinate thiokinase (D) Fumarse
Description : Citrate is converted to isocitrate by aconitase which contains (A) Ca++ (B) Fe++ (C) Zn++ (D) Mg++
Last Answer : B
Description : An important zinc containing enzyme is (A) Carboxypeptidase A (B) Isocitrate dehydrogenase (C) Cholinesterate (D) Lipoprotein lipase
Description : An enzyme catalyzing oxidoreduction, using oxygen as hydrogen acceptor is (A) Cytochrome oxidase (B) Lactate dehydrogenase (C) Malate dehydrogenase (D) Succinate dehydrogenase
Description : NADPH is produced when this enzyme acts (A) Pyruvate dehydrogenase (B) Malic enzyme (C) Succinate dehydrogenase (D) Malate 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 : NADPH required for fatty acid synthesis can come from (A) Hexose monophosphate shunt (B) Oxidative decarboxylation of malate (C) Extramitochondrial oxidation of isocitrate (D) All of these
Description : The metabolism of protein is integrated with that of carbohydrate and fat through (A) Oxaloacetate (B) Citrate (C) Isocitrate (D) Malate
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 : Which of the following is an allosteric enzyme? (A) Phosphohexose isomerase (B) Phosphotriose isomerase (C) Lactate dehydrogenase (D) Phosphofructokinase
Description : Fluoride inhibits ______ and arrests glycolysis. (A) Glyceraldehyde-3-phosphate dehydrogenase (B) Aconitase (C) Enolose (D) Succinate dehydrogenase
Last Answer : C
Description : Isocitrate dehydrogenases is (A) Aerobic dehydrogenase (B) Anaerobic dehydrogenase (C) Hydroperoxidase (D) Oxygenase
Description : Isocitrate dehydrogenase can use __________ as a cofactor. (A) NAD+ only (B) NADP+ only (C) NAD+ or NADP+ (D) FMN and FAD
Description : Thiamine is essential for (A) Pyruvate dehydrogenase (B) Isocitrate dehydrogenase (C) Succinate dehydrogenase (D) Acetyl CoA synthetase ENZYMES 165
Description : Isocitrate dehydrogenase is allosterically inhibited by (A) Oxalosuccinate (B) α-Ketoglutarate (C) ATP (D) NADH
Description : Which of the following is not having an apoenzyme and coenzyme? (A) Lactate dehydrogenase (B) Succinate dehydrogenase (C) Malate dehydrogenase (D) Pepsin
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 : NAD is required as a coenzyme for (A) Malate dehydrogenase (B) Succinate dehydrogenase (C) Glucose-6-phosphate dehydrogenase (D) HMG CoA reductae
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 : All of the following are allosteric enzymes except (A) Citrate synthetase (B) a-Ketoglutarate dehdrogenase (C) Succinate thiokinase (D) Succinate dehydrogenase
Description : An allosteric inhibitor of pyruvate dehydrogenase is (A) Acetyl CoA (B) ATP (C) NADH (D) Pyruvate
Description : Pyruvate dehydrogenase complex is regulated by (A) Covalent modification (B) Allosteric regulation (C) Both (A) and (B) (D) None of these
Description : Allosteric inhibitor of glutamate dehydrogenase is (A) ATP (B) ADP (C) AMP (D) GMP
Description : In pentose phosphate pathway, D-ribulose5-phosphate is converted to D-ribose-5- phosphate by the enzyme: (A) Fumarase (B) Ketoisomerase (C) G-6-PD (D) Epimerase
Description : The enzyme -ketoglutarate dehydrogenase in the citric acid cycle requires (A) Lipoate (B) Folate (C) Pyridoxine (D) Inositol
Description : A competitive inhibitor of succinic dehydrogenase is (a) α-ketoglutarate (b) malate (c) malonate (d) oxaloacetate.
Last Answer : (c) malonate
Description : An enzyme in saliva which hydrolyzes starch is (A) Pepsinogen (B) Chymotrysin (C) α-Amylase (D) Malate
Description : All of the following intermediates of citric acid cycle can be formed from amino acids except (A) α-Ketoglutarate (B) Fumarate (C) Malate (D) Oxaloacetate
Description : A carrier molecule in the citric acid cycle is (A) Acetyl-CoA (B) Citrate (C) Oxaloacetate (D) Malate
Description : The integrator between the TCA cycle and urea cycle is (A) Fumarate (B) Malate (C) Pyruvate (D) Citrate