Description : Glucose-6-phosphate is an allosteric inhibitor of (A) Glucokinase (B) Hexokinase (C) Phosphohexose isomerase (D) None of these
Last Answer : Answer : B
Description : Conversion of glucose to glucose-6- phosphate in human liver is by (A) Hexokinase only (B) Glucokinase only (C) Hexokinase and glucokinase (D) Glucose-6-phosphate dehydrogenase
Last Answer : C
Description : ATP is a co-substrate as well as an allosteric inhibitor of (A) Phosphofructokinase (B) Hexokinase (C) Glucokinase (D) None of these
Last Answer : Answer : A
Description : Conversion of glucose to glucose-6-phosphate, the first irreversible reaction of glycolysis, is catalysed by (a) phosphofructokinase (b) aldolase (c) hexokinase (d) enolase.
Last Answer : (c) hexokinase
Description : Fructose 2, 3 bi phosphate is a powerful allosteric activator of (A) Fructose 1, 6 diphosphatase (B) Phosphofructokinase (C) Hexokinase (D) Fructokinase
Description : Which one of the following enzymes requires a coenzyme derived from the vitamin whose structure is shown below? (A) Enoyl CoA hydratase (B) Phosphofructokinase (C) Glucose-6-phosphatase (D) Glucose-6-phosphate dehydrogenase
Last Answer : Answer : D
Description : During fasting, glucose is phosphorylated mainly by (A) Hexokinase (B) Glucokinase (C) Both (A) and (B) (D) None of these
Description : At low blood glucose concentration, brain but not liver will take up glucose. It is due to the (A) Low Km of hexokinase (B) Low Km of glucokinase (C) Specificity of glucokinase (D) Blood brain barrier
Description : Hexokinase has a high affinity for glucose than (A) Fructokinase (B) Galactokinase (C) Glucokinase (D) All of the above
Description : Glucokinase (A) Is widely distributed and occurs in most mammalian tissues (B) Has a high km for glucose and hence is important in the phosphorylation of glucose primarily after ingestion of a carbohydrate rich meal (C) Is widely distributed in Prokaryotes (D) None of these
Last Answer : B
Description : The 4 rate limiting enzymes of gluconeogenesis are (A) Glucokinase, Pyruvate carboxylae phosphoenol pyruvate carboxykinase and glucose-6-phosphatase (B) Pyruvate carboxylase, phosphoenol ... fructokinase, pyruvate carboxylase, phosphoenol pyruvate carboxykinase and fructose 1, 6 diphosphatase
Description : A gluconeogenic enzyme among the following is (A) Phosphofructokinase (B) Pyruvate kinase (C) Phosphoenol pyruvate carboxykinase (D) Glucokinase
Last Answer : Answer : C
Description : The enzyme that converts glucose to glucose-6-phosphate is (A) Phosphatase (B) Hexokinase (C) Phosphorylase (D) Glucose synthetase
Description : The hexose monophosphate pathway includes the enzyme: (A) Maltase dehydrogenase (B) Hexokinase (C) α-Ketoglutarate dehydrogenase (D) Glucose-6-phosphate dehydrogenase
Description : Hexokinase is inhibited in an allosteric manner by (A) Glucose-6-Phosphate (B) Glucose-1-Phosphate (C) Fructose-6-phosphate (D) Fructose-1, 6-biphosphate
Description : One of the enzymes regulating glycolysis is (A) Phosphofructokinase (B) Glyceraldehyde-3-phosphate dehydrogenase (C) Phosphotriose isomerase (D) Phosphohexose isomerase
Description : Insulin decreases the synthesis of (A) Hexokinase (B) Glucokinase (C) PEP carboxykinase (D) Glycogen synthetase
Description : The glycolysis is regulated by (A) Hexokinase (B) Phosphofructokinase (C) Pyruvate kinase (D) All of these
Last Answer : D
Description : Hemolytic anemia is caused by the deficiency of certain enzymes of the pentose phosphate pathway, the principal enzyme involved is (A) Glucose-6-phosphate dehydrogenase (B) Aldolase (C) Fructose 1, 6-bisphosphatase (D) Phosphohexose isomerase
Description : Given that the standard free energy change (∆G°) for the hydrolysis of ATP is -7.3 K cal/mol and that for the hydrolysis of Glucose 6-phosphate is -3.3 Kcal/mol, the ∆G° for the phosphorylation of glucose is Glucose + ATP → ... -10.6 Kcal/mol (B) -7.3 Kcal/mol (C) -4.0 Kcal/mol (D) +4.0 Kcal/mol
Description : Which one of the following would be expected in pyruvate kinase deficiency? (A) Increased levels of lactate in the R.B.C (B) Hemolytic anemia (C) Decreased ratio of ADP to ATP in R.B.C (D) Increased phosphorylation of Glucose to Glucose-6-phosphate
Description : Two examples of substrate level phosphorylation in EM pathway of glucose metabolism are in the reactions of (A) 1,3 bisphosphoglycerate and phosphoenol pyruvate (B) Glucose-6 phosphate ... phosphate (C) 3 phosphoglyceraldehyde and phosphoenolpyruvate (D) 1,3 diphosphoglycerate and 2-phosphoglycerate
Last Answer : A
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 : An example of competitive inhibition of an enzyme is the inhibition of a. Succinic dehydrogenase by malonic acid b. Cytochrome oxidase by cyanide c. Hexokinase by glucose-6-phosphate d. Carbonic anhydrase by carbon dioxide
Last Answer : Ans: A
Description : Which of the following is not an enzyme involved in glycolysis? (A) Euolase (B) Aldolose (C) Hexokinase (D) Glucose oxidase
Description : The glycerol for fatty acid esterification in adipocytes is (A) For the most part, derived from glucose (B) Obtained primarily from phosphorylation of glycerol by glycerol kinase (C) Formed from gluconeogenesis (D) Formed from glycogenolysis ENZYMES 153
Description : The reaction catalysed by phosphofructokinase (A) Is activated by high concentrations of ATP and citrate (B) Uses fruitose-1-phosphate as substrate (C) Is the rate-limiting reaction of the glycolytic pathway (D) Is inhibited by fructose 2, 6-bisphosphate
Description : Glucocorticoids increase the synthesis of all of the following except (A) Glucokinase (B) Glucose-6-phosphatase (C) Fructose-1, 6-biphosphatase (D) Pyruvate carboxylase
Description : Pompe ’s d isease is caused due to deficiency of (A) Lysosomal α-1→4 and 1→6-glucosidase (B) Glucose-6-phosphatase (C) Glycogen synthase (D) Phosphofructokinase
Description : McArdle’s disease is due to the deficiency of (A) Glucose-6-phosphatase (B) Phosphofructokinase (C) Liver phosphorylase (D) muscle phosphorylase
Description : Which of the following is present as a marker in lysosomal enzymes to direct them to their destination? (A) Glucose-6-phosphate (B) Mannose-6-phosphate (C) Galactose-6-phosphate (D) N-Acetyl neuraminic acid
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 : Synthesis of the following enzymes is increased during starvation. (A) Digestive enzymes (B) Gluconeogenic enzymes (C) Urea cycle enzymes (D) Glucokinase
Description : Hexokinase (Glucose + ATP → Glucose-6– P + ADP) belongs to the category: (A) Transferases (B) Lysases (C) Oxidoreductases (D) Isomerases
Description : The “Primaquin sensitivity types of haemolytic anaemia has been found to relate to reduced R.B.C activity of which enzyme? (A) Pyruvate kinase deficiency (B) Glucose-6-phosphatase deficiency (C) Glucose-6-p dehydrogenase deficiency (D) Hexokinase deficiency
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 : The enzymes present in the membrane of mitochondria are (A) Flavoproteins and cytochromes (B) Fumarase and lipase (C) Enolase and catalase (D) Hexokinase and zymase
Description : Pasteur effect is (A) Inhibition of glycolysis (B) Oxygen is involved (C) Inhibition of enzyme phosphofructokinase (D) All of these
Description : An enzyme involved in gluconeogenesis is (A) Pyruvate kinase (B) Pyruvate carboxylase (C) Hexokinase (D) Phosphohexose isomerase
Description : Which one of the following statements is incorrect? (A) Insulin increases glucose phosphorylation (B) Insulin increases glycolysis (C) Insulin augments HMP shunt (D) Insulin promotes gluconeogenesis
Description : In non shivering thermogenesis (A) Glucose is oxidized to lactate (B) Fatty acids uncouple oxidative phosphorylation (C) Ethanol is formed (D) ATP is burned for heat production
Description : All the following statements about brown adipose tissue are true except (A) It is rich in cytochromes (B) It oxidizes glucose and fatty acids (C) Oxidation and phosphorylation are tightly coupled in it (D) Dinitrophenol has no effect on it
Description : Tissues form lactic acid from glucose. This phenomenon is termed as (A) Aerobic glycolysis (B) Oxidation (C) Oxidative phosphorylation (D) Anaerobic glycolysis
Description : One of the causes of hemolytic jaundice is (A) G-6 phosphatase deficiency (B) Increased conjugated bilirubin (C) Glucokinase deficiency (D) Phosphoglucomutase deficiency
Description : The regulatory enzyme in HMP shunt is (A) Glucose-6-phosphate dehydrogenase (B) 6-Phosphogluconate dehydrogenase (C) Both (A) and (B) (D) None of these
Description : The following are true about the oxidation of glucose: a. glycolysis produces 3% of the energy ultimately obtained from glucose b. the first stage of glycolysis involves phosphorylation of glucose to 1,6-fructose biphosphate. c. glucose enters the Kreb's cycle as pyruvate d. all above
Last Answer : all above
Description : Phosphofructokinase is allosterically inhibited by (A) Fructose-1, 6-biphosphate (B) Lactate (C) Pyruvate (D) Citrate
Description : Fructose-2, 6-biphosphate is formed by the action of (A) Phosphofructokinase-1 (B) Phosphofructokinase-2 (C) Fructose biphosphate isomerase (D) Fructose-1, 6-biphosphatase
Description : I-cell disease results from absence of the following from lysosomal enzymes: (A) Signal sequence (B) Mannose-6-phosphate (C) Sialic acid (D) A serine residue
Description : Oxidative phosphorylation is (a) formation of ATP by transfer of phosphate group from a substrate to ADP (b) oxidation of phosphate group in ATP (c) addition of phosphate group to ATP (d) formation of ATP by energy released from electrons removed during substrate oxidation.
Last Answer : (d) formation of ATP by energy released from electrons removed during substrate oxidation.