Description : A substance which competes with iodide uptake mechanism by thyroid gland is (A) Thiocynate (B) Iodoacetate (C) Fluoride (D) Fluoroacetate
Last Answer : Answer : A
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
Last Answer : Answer : D
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 : 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
Last Answer : Answer : C
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
Last Answer : Answer : B
Description : Isocitrate dehydrogenase is allosterically inhibited by (A) Oxalosuccinate (B) α-Ketoglutarate (C) ATP (D) NADH
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 : Mitochondrial α-ketoglutarate dehydrogenase complex requires all the following to function except (A) CoA (B) FAD (C) NAD+ (D) NADP+
Description : Which one of the following compounds cannot give rise to the net synthesis of Glucose? (A) Lactate (B) Glycerol (C) α-ketoglutarate (D) Acetyl CoA
Last Answer : B
Description : Before pyruvic acid enters the TCA cycle it must be converted to (A) Acetyl CoA (B) Lactate (C) α-ketoglutarate (D) Citrate
Last Answer : A
Description : Activity of cytochrome oxidase is inhibited by (A) Sulphite (B) Sulphate (C) Arsenite (D) Cyanide
Description : A specific inhibitor for succinate dehydrogenase is (A) Arsenite (B) Malonate (C) Citrate (D) Fluoride
Description : A specific inhibitor for succinate dehydrogenase is (A) Arsenine (B) Arsenite (C) Citrate (D) Fluoride ENZYMES 147
Description : In the biosynthesis of heme, condensation between succinyl CoA and glycine requires (A) NAD+ (B) FAD (C) NADH + H+ (D) B6-phosphate
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 : The source of all the carbon atoms in cholesterol is (A) Acetyl-CoA (B) Bicarbonate (C) Propionyl-CoA (D) Succinyl-CoA
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
Description : In extra hepatic tissues, one mechanism for utilization of acetoacetate involves (A) Malonyl-CoA (B) Succinyl-CoA (C) Propionyl-CoA (D) Acetyl-CoA
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 : The reaction succinyl COA to succinate requires (A) CDP (B) ADP (C) GDP (D) NADP+
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 : What are the co-enzymes required for the conversion of propionyl CoA to succinyl CoA?
Last Answer : Biotin, ATP, Vitamin B12.
Description : FAD containing enzyme, catalyzing formation of α, β unsaturated fatty acyl CoA derivative. (A) Acyl CoA dehydrogenase (B) Enoyl hydrase (C) β-OH acyl CoA dehydrogenase (D) Thiolase
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 : Malonate is an inhibitor of (A) Malate dehydrogenase (B) α-Ketoglutarate dehydrogenase (C) Succinate dehydrogenase (D) Isocitrate dehydrogenase
Description : The hexose monophosphate pathway includes the enzyme: (A) Maltase dehydrogenase (B) Hexokinase (C) α-Ketoglutarate dehydrogenase (D) Glucose-6-phosphate 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
Description : In TCA cycle, oxalosuccinate is converted to α-ketoglutarate by the enzyme: (A) Fumarase (B) Isocitrate dehydrogenase (C) Aconitase (D) Succinase
Description : The reaction catalysed by α-ketoglutarate dehydrogenase in the citric acid cycle requires (A) NAD (B) NADP (C) ADP (D) ATP
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 : Lipoic acid is a conenzyme for (A) Pyruvate dehydrogenase (B) α-Ketoglutarate dehydrogenae (C) Both (A) and (B) (D) None of these
Description : An important finding in Histidinemia is (A) Impairment of conversion of α-Glutamate to α-ketoglutarate (B) Speech defect (C) Decreased urinary histidine level (D) Patients can not be treated by diet
Description : All of the following are required for synthesis of alanine except (A) Pyruvate (B) α-ketoglutarate (C) Glutamate (D) Pyridoxal phosphate
Description : Alanine can be synthesized from (A) Glutamate and α-ketoglutarate (B) Pyruvate and glutamate (C) Pyruvate and α-ketoglutarate (D) Asparate and α-ketoglutarate
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
Last Answer : D
Description : Which of the following enzymes in Glycolytic pathway is inhibited by fluoride? (A) Glyceraldehyde-3-p dehydrogenase (B) Phosphoglycerate kinase (C) Pyruvate kinase (D) Enolase
Description : Synthesis of prostaglandinsis is inhibited by (A) Aspirin (B) Arsenic (C) Fluoride (D) Cyanide
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 : All the following statements about acetyl CoA carboxylase are true except: (A) It is activated by citrate (B) It is inhibited by palmitoyl CoA (C) It can undergo covalent modification (D) Its dephosphorylated form is inactive
Description : β-oxidation of fatty acids is inhibited by (A) NADPH (B) Acetyl CoA (C) Malonyl CoA (D) None of these
Description : The activity of HMG-CoA reductase is inhibited by (A) A fungal inhibitor mevastatin (B) Probucol (C) Nicotinic acid (D) Clofibrate
Description : A competitive inhibitor of succinic dehydrogenase is (a) α-ketoglutarate (b) malate (c) malonate (d) oxaloacetate.
Last Answer : (c) malonate
Last Answer : (A) Aspirin
Description : For each of the first 7-acetyl-CoA molecules formed by α-oxidation of palmitic acid, the yield of high energy phosphates is (A) 12 (B) 24 (C) 30 (D) 35
Description : In synthesis of Triglyceride from α-Glycero phosphate and acetyl CoA, the first intermediate formed is (A) β-diacyl glycerol (B) Acyl carnitine (C) Monoacyl glycerol(D) Phosphatidic acid
Description : Acyl-CoA dehydrogenase converts Acyl CoA to α-β unsaturated acyl-CoA in presence of the coenzyme: (A) NAD+ (B) NADP+ (C) ATP (D) FAD
Description : Insulin regulates fatty acid synthesis by (A) Dephosphorylating of acetyl CoA carboxylase (B) Activating phosphorylase (C) Inhibiting malonyl CoA formation (D) Controlling carnitine-Acyl CoA transferase activity
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