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.

1 Answer

Answer :

(b) succinic acid to fumaric acid

Related questions

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 : 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 : Formation of succinyl-CoA from α-Ketoglutarate is inhibited by (A) Fluoroacetate (B) Arsenite (C) Fluoride (D) Iodoacetate

Last Answer : Answer : B

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 : 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 : Link between glycolysis, Krebs’ cycle and β-oxidation of fatty acid or carbohydrate and fat metabolism is (a) oxaloacetic acid (b) succinic acid (c) citric acid (d) acetyl CoA.

Last Answer : (d) acetyl CoA.

Description : Which of the following is the key intermediate compound linking glycolysis to the Krebs’ cycle? (a) Malic acid (b) Acetyl CoA (c) NADH (d) ATP

Last Answer : (b) Acetyl CoA

Description : Mitochondrial α-ketoglutarate dehydrogenase complex requires all the following to function except (A) CoA (B) FAD (C) NAD+ (D) NADP+

Last Answer : Answer : D

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 : 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 : A competitive inhibitor of succinic dehydrogenase is (a) α-ketoglutarate (b) malate (c) malonate (d) oxaloacetate.

Last Answer : (c) malonate

Description : Dehydrogenation of succinic acid to fumaric acid requires the following hydrogen carrier: (A) NAD+ (B) NADP+ (C) flavoprotein (D) Glutathione

Last Answer : C

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 : 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

Last Answer : Answer : A

Description : In the biosynthesis of heme, condensation between succinyl CoA and glycine requires (A) NAD+ (B) FAD (C) NADH + H+ (D) B6-phosphate

Last Answer : Answer : D

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 : 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 : What are the co-enzymes required for the conversion of propionyl CoA to succinyl CoA?

Last Answer : Biotin, ATP, Vitamin B12.

Description : Conversion of ammonia to urea is done by (a) ornithine cycle (b) arginine cycle (c) fumaric cycle (d) citrulline cycle.

Last Answer : (a) ornithine cycle

Description : Tricarboxylic acid cycle to be continuous requires the regeneration of (A) Pyruvic acid (B) oxaloacetic acid (C) α-oxoglutaric acid (D) Malic acid

Last Answer : B

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

Last Answer : Answer : C

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 reaction catalysed by α-ketoglutarate dehydrogenase in the citric acid cycle requires (A) NAD (B) NADP (C) ADP (D) ATP

Last Answer : Answer : A

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

Last Answer : Answer : C

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

Last Answer : Answer : A

Description : During each cycle of β-oxidation of fatty acid, all the following compounds are generated except (A) NADH (B) H2O (C) FAD (D) Acyl CoA

Last Answer : Answer : B

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

Last Answer : Answer : B

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

Last Answer : Answer : A

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

Last Answer : Answer : D

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 : The cofactor or its derivative required for the conversion of acetyl CoA to malonylCoA is (A) FAD (B) ACP (C) NAD+ (D) Biotin

Last Answer : Answer : D

Description : β-Oxidation of odd-carbon fatty acid chain produces (A) Succinyl CoA (B) Propionyl CoA (C) Acetyl CoA (D) Malonyl CoA

Last Answer : Answer : D

Description : Connecting link between glycolysis and Krebs’ cycle before pyruvate entering Krebs’ cycle is changed to (a) oxaloacetate (b) PEP (c) pyruvate (d) acetyl CoA.

Last Answer : (d) acetyl CoA.

Description : Oxidative phosphorylation involves (A) Electron transport system (B) Substrate level phosphorylation (C) Reaction catalyzed by succinic thiokinase in TCA cycle (D) None of the above

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Description : Lipoic acid is a conenzyme for (A) Pyruvate dehydrogenase (B) α-Ketoglutarate dehydrogenae (C) Both (A) and (B) (D) None of these

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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

Last Answer : Answer : A

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Last Answer : Answer : A

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Last Answer : Porphyrin biosynthesis, activation of acetoacetate, and oxidation in TCA cycle.

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Last Answer : Odd chain fatty acids, propionic acid, valine, isoleucine, threonine.

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Last Answer : A. Conversion of malonic acid to succinic acid

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Last Answer : NADH and FADH2

Description : The overall goal of glycolysis, Krebs’ cycle and the electron transport system is the formation of (a) ATP in one large oxidation reaction (b) sugars (c) nucleic acids (d) ATP in small stepwise units

Last Answer : d) ATP in small stepwise units.

Description : The hydrogen acceptor used in pentose phosphate pathway is (A) NAD (B) NADP (C) FAD (D) FMN

Last Answer : Answer : B

Description : Pantothenic acid acts on (A) NADP (B) NADPH (C) FAD (D) CoA

Last Answer : Answer : B

Description : Isocitrate dehydrogenase is allosterically inhibited by (A) Oxalosuccinate (B) α-Ketoglutarate (C) ATP (D) NADH

Last Answer : Answer : C

Description : Malonate is an inhibitor of (A) Malate dehydrogenase (B) α-Ketoglutarate dehydrogenase (C) Succinate dehydrogenase (D) Isocitrate dehydrogenase

Last Answer : Answer : C

Description : The hexose monophosphate pathway includes the enzyme: (A) Maltase dehydrogenase (B) Hexokinase (C) α-Ketoglutarate dehydrogenase (D) Glucose-6-phosphate dehydrogenase

Last Answer : Answer : D