Description : Conversion of fatty acyl-CoA to an acylCoA derivative having 2 more carbon atoms involves as acetyl donar: (A) Acetyl-CoA (B) Succinyl-CoA (C) Propionyl-CoA (D) Malonyl-CoA
Last Answer : Answer : D
Description : The source of all the carbon atoms in cholesterol is (A) Acetyl-CoA (B) Bicarbonate (C) Propionyl-CoA (D) Succinyl-CoA
Last Answer : Answer : A
Description : In extra hepatic tissues, one mechanism for utilization of acetoacetate involves (A) Malonyl-CoA (B) Succinyl-CoA (C) Propionyl-CoA (D) Acetyl-CoA
Last Answer : Answer : B
Description : Fatty acids with odd number of carbon atoms yield acetyl-CoA and a molecule of (A) Succinyl-CoA (B) Propionyl-CoA (C) Malonyl-CoA (D) Acetoacetyl-CoA
Description : β-Oxidation of odd-carbon fatty acid chain produces (A) Succinyl CoA (B) Propionyl CoA (C) Acetyl CoA (D) Malonyl CoA
Description : In Krebs’ cycle, the FAD precipitates as electron acceptor during the conversion of (a) fumaric acid to malic acid (b) succinic acid to fumaric acid (c) succinyl CoA to succinic acid (d) α-ketoglutarate to succinyl CoA.
Last Answer : (b) succinic acid to fumaric acid
Description : Which statement is wrong for Krebs' cycle? (a) There is one point in the cycle where FAD+ is reduced to FADH2. (b) During conversion of succinyl CoA to succinic acid, a molecule of GTP is synthesised. (c ... citric acid. (d) There are three points in the cycle where NAD+ is reduced to NADH + H+.
Last Answer : (c) The cycle starts with condensation of acetyl group (acetyl CoA) with pyruvic acid to yield citric acid.
Description : Ceramide is formed by the combination of sphingosine and (A) Acetyl-CoA (B) Acyl-CoA (C) Malonyl-CoA (D) Propionyl-CoA
Description : Biotin is a coenzyme for (A) Pyruvate carboxylase (B) Acetyl CoA carboxylase (C) Propionyl CoA carboxylase (D) All of these
Description : As a result of each oxidation a long chain fatty acid is cleaved to give (A) An acid with 3-carbon less and propionyl CoA (B) An acid with 2-carbon less and acetyl CoA (C) An acid with 2-carbon less and acetyl CoA (D) An acid with 4-carbon and butyryl CoA
Description : Propionyl CoA formed oxidation of fatty acids having an odd number of carbon atoms is converted into (A) Acetyl CoA (B) Acetoacetyl CoA (C) D-Methylmalonyl CoA (D) Butyryl CoA
Last Answer : Answer : C
Description : Propionyl CoA is formed on oxidation of (A) Monounsaturated fatty acids (B) Polyunsaturated fatty acids (C) Fatty acids with odd number of carbon atoms (D) None of these FATS AND FATTY ACID METABOLISM 83
Description : What is the further metabolism of propionyl CoA?
Last Answer : Propionyl CoA is first carboxylated to methyl malonyl CoA and then to form succinyl CoA. The succinyl CoA then enters TCA cycle.
Description : In the biosynthesis of heme, condensation between succinyl CoA and glycine requires (A) NAD+ (B) FAD (C) NADH + H+ (D) B6-phosphate
Description : In the biosynthesis of the iron protoporphyrin, the product of the condensation between succinyl-CoA and glycine is (A) α-Amino β-ketoadipic acid (B) δ-Aminolevulinate (C) Hydroxymethylbilane (D) Uroporphyrinogen I
Description : Heme is synthesized from (A) Succinyl-CoA and glycine (B) Active acetate and glycine (C) Active succinate and alanine (D) Active acetate and alanine
Description : Formation of succinyl-CoA from α-Ketoglutarate is inhibited by (A) Fluoroacetate (B) Arsenite (C) Fluoride (D) Iodoacetate
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 reaction succinyl COA to succinate requires (A) CDP (B) ADP (C) GDP (D) NADP+
Last Answer : B
Description : Succinyl CoA is utilised for what purposes?
Last Answer : Porphyrin biosynthesis, activation of acetoacetate, and oxidation in TCA cycle.
Description : Succinyl CoA is generated from which substances?
Last Answer : Odd chain fatty acids, propionic acid, valine, isoleucine, threonine.
Description : A cofactor required for the conversion of acetyl-CoA to malonyl-CoA in extramitochondrial fatty acid synthesis is (A) Biotin (B) FMN (C) NAD (D) NADP
Description : The cofactor or its derivative required for the conversion of acetyl CoA to malonylCoA is (A) FAD (B) ACP (C) NAD+ (D) Biotin
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 : Thiamine is essential for (A) Pyruvate dehydrogenase (B) Isocitrate dehydrogenase (C) Succinate dehydrogenase (D) Acetyl CoA synthetase ENZYMES 165
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
Description : The carbon chain of fatty acids is shortened by 2 carbon atoms at a time. This involves successive reactions catalysed by 4-enzymes. These act the following order: (A) Acetyl CoA dehydrogenase, ... CoA dehydrogenase (D) Enoyl hydrase, β-OH acyl CoA dehydrogenase, acyl CoA dehydrogenase, thiolose,
Description : Which one of the following cofactors must be utilized during the conversion of acetyl CoA to malonyl CoA? (A) TPP (B) ACP (C) NAD+ (D) Biotin
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 : 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 : Which of the following cofactors or their derivatives must be present for the conversion of acetyl CoA to malonyl CoA extramitochondrial fatty acid synthesis? (A) Biotin (B) FAD (C) FMN (D) ACP
Description : Fatty acids can not be converted into carbohydrates in the body, as the following reaction is not possible: (A) Conversion of glucose-6-phosphate into glucose (B) Fructose 1, 6 diphosphate to ... phosphate (C) Transformation of acetyl CoA to pyruvate (D) Formation of acetyl CoA from fatty acids
Description : In the extra mitochondrial synthesis of fatty acids, CO2 is utilized (A) To keep the system anaerobic and prevent regeneration of acetyl CoA (B) In the conversion of malonyl to CoA hydroxybutyryl CoA (C ... of acetyl CoA to malonyl CoA (D) In the formation of acetyl CoA from 1 carbon intermediates
Description : The enzyme acyl-CoA synthase catalyses the conversion of a fatty acid of an active fatty acid in the presence of (A) AMP (B) ADP (C) ATP (D) GTP
Description : The conversion of pyruvate to acetyl CoA and CO2 (A) Is reversible (B) Involves the participation of lipoic acid (C) Depends on the coenzyme biotin (D) Occurs in the cytosol
Description : Fatty acids cannot be converted into carbohydrates in the body as the following reaction is not possible. (A) Conversion of glucose-6-phosphate into glucose (B) Fructose 1,6-bisphosphate to fructose- ... (C) Transformation of acetyl CoA to pyruvate (D) Formation of acetyl CoA from fatty acids
Last Answer : C
Description : What are the co-enzymes required for the reaction?
Last Answer : Biotin and ATP.
Description : Group transferring Co-enzyme is (A) CoA (B) NAD+ (C) NADP+ (D) FAD+
Description : Which co-enzyme is not involved in oxidative decarboxylation of pyruvic acid? (A) TPP (B) Mg++ (C) Biotin (D) CoA-SH
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 : 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 : During which stage in the complete oxidation of glucose are the greatest number of ATP molecules formed from ADP? (a) Glycolysis (b) Krebs’ cycle (c) Conversion of pyruvic acid to acetyl CoA (d) Electron transport chain
Last Answer : (d) Electron transport chain
Description : Coalification means the (A) Process of conversion of lignite into anthracite (B) Underground gasification of coal (C) Complete combustion of coal (D) Direct hydrogenation of coa
Last Answer : (A) Process of conversion of lignite into anthracite
Description : Magnesium ions are required in the reactions involving (A) NAD (B) FAD (C) ATP (D) CoA
Description : All the following statements about acetyl CoA carboxylase are true except (A) It is required for de novo synthesis of fatty acids (B) It is required for mitochondrial elongation of fatty acids ( ... for microsomal elongation of fatty acids (D) Insulin converts its inactive form into its active form
Description : Acetyl CoA required for de novo synthesis of fatty acids is obtained from (A) Breakdown of existing fatty acids (B) Ketone bodies (C) Acetate (D) Pyruvate
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 : Pyruvate dehydrogenase a multienzyme complex is required for the production of (A) Acetyl-CoA (B) Lactate (C) Phosphoenolpyruvate (D) Enolpyruvate
Description : Biotin is required for the reaction of CO2 with (A) Water (B) Acetyl CoA (C) NH3 (D) Incorporation of carbon 6 in purine
Description : NAD is required as a coenzyme for (A) Malate dehydrogenase (B) Succinate dehydrogenase (C) Glucose-6-phosphate dehydrogenase (D) HMG CoA reductae