Description : All of the following are intermediates of citric acid cycle except (A) Oxalosuccinate (B) Oxaloacetate (C) Pyruvate (D) Fumarate
Last Answer : Answer : C
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 : Out of 24 mols of ATP formed in TCA cycle, 2 molecules of ATP can be formed at “substrate level” by which of the following reaction ? (A) Citric acid→ Isocitric acid (B) Isocitrate→ Oxaloacetate (C) Succinic acid→ Fumarate (D) Succinylcat→ Succinic acid
Last Answer : D
Description : The integrator between the TCA cycle and urea cycle is (A) Fumarate (B) Malate (C) Pyruvate (D) Citrate
Last Answer : Answer : A
Description : Mitochondrial membrane is freely preamble to (A) Pyruvate (B) Malate (C) Oxaloacetate (D) Fumarate
Last Answer : Answer : B
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 : 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 : 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 : The carrier of the citric acid cycle is (A) Succinate (B) Fumarate (C) Malate (D) Oxaloacetate
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 : Active transport of sugar is depressed by the agent: (A) Oxaloacetate (B) Fumarate (C) Malonate (D) Succinate
Last 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
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 : Which of the following intermediates of metabolism can be both a precursor and a product of glucose? (A) Lactate (B) Pyruvate (C) Alanine (D) Acetyl-CoA
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 : Fully activated pyruvate carboxylase depends upon the presence of (A) Malate and Niacin (B) Acetyl CoA and biotin (C) Acetyl CoA and thiamine pyrophosphate (D) Oxaloacetate and biotin
Description : Pyridoxal phosphate is a coenzyme for (A) Glutamate oxaloacetate transaminase (B) Glutamate pyruvate transaminase (C) Tyrosine transaminase (D) All of these
Description : The coenzyme required for conversion of pyruvate to oxaloacetate is (A) FAD (B) NAD (C) TPP (D) Biotin
Description : While citrate is converted to isocitrate in the mitochondria, it is converted to _______ in the cytosol. (A) Acetyl CoA + oxaloacetate (B) Acetyl CoA + malonyl CoA (C) Acetyl CoA + Pyruvate (D) Acetyl CoA + acetoacetyl CoA
Description : Which of the following reactions is unique to gluconeogenesis? (A) Lactate Pyruvate (B) Phosphoenol pyruvate pyruvate (C) Oxaloacetate phosphoenol pyruvate (D) Glucose-6-phosphate Fructose-6-phosphate
Description : For conversion of oxaloacetate to phosphoenol pyruvate, high energy molecule is required in the form of (A) GTP only (B) ITP only (C) GTP (or) ITP (D) None of these
Description : In presence of the following cofactor, pyruvate carboxylase converts pyruvate to oxaloacetate: (A) ATP, Protein and CO2 (B) CO2 and ATP (C) CO2 (D) Protein
Last Answer : A
Description : Which of the following compound is a positive allosteric modifier of the enzyme pyruvate carboxylase? (A) Biotin (B) Acetyl CoA (C) Oxaloacetate (D) ATP
Description : An aneplerotic reaction which sustains the availability of oxaloacetate is the carboxylation of (A) Glutamate (B) Pyruvate (C) Citrate (D) Succinate
Last Answer : B
Description : Pyruvate carboxylase reaction (pyruvate to oxaloacetate) needs which co-enzyme?
Last Answer : Biotin and ATP.
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 : 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 : A compound serving a link between citric acid cycle and urea cycle is (A) Malate (B) Citrate (C) Succinate (D) Fumarate
Description : If all the enzymes, intermediates and cofactors of the citric acid cycle as well as an excess of the starting substrate acetylCoA are present and functional in an organelle free solution at the appropriate ... oxygen (B) Half life of enzyme (C) Turnover of intermediates (D) Reduction of cofactors
Description : Which of the following statements regarding T.C.A cycle is true? (A) It is an anaerobic process (B) It occurs in cytosol (C) It contains no intermediates for Gluconeogenesis (D) It is amphibolic in nature
Description : cAMP is so called because it is formed during (A) TCA cycle (B) Urea cycle (C) Rhodopsin cycle (D) It has a cyclic structure
Description : In TCA cycle, oxalosuccinate is converted to α-ketoglutarate by the enzyme: (A) Fumarase (B) Isocitrate dehydrogenase (C) Aconitase (D) Succinase
Description : The most important source of reducing equivalents for FA synthesis on the liver is (A) Glycolysis (B) HMP-Shunt (C) TCA cycle (D) Uronic acid pathway
Description : Citrulline is an intermediate of (A) TCA cycle (B) Urea cycle (C) Pentose cycle (D) Calvin cycle
Description : Most of the metabolic pathways are either anabolic or catabolic. Which of the following pathways is considered as “amphibolic” in nature? (A) Glycogenesis (B) Glycolytic pathway (C) Lipolysis (D) TCA cycle
Description : Before pyruvic acid enters the TCA cycle it must be converted to (A) Acetyl CoA (B) Lactate (C) α-ketoglutarate (D) Citrate
Description : One molecule of glucose gives ______ molecules of CO2 in EM-TCA cycle. (A) 6 (B) 3 (C) 1 (D) 2
Description : Substrate level phosphorylation in TCA cycle is in step: (A) Isocitrate dehydrogenase (B) Malate dehydrogenase (C) Aconitase (D) Succinate thiokinase
Description : The number of molecules of ATP produced by the total oxidation of acetyl CoA in TCA cycle is (A) 6 (B) 8 (C) 10 (D) 12
Description : Our body can get pentoses from (A) Glycolytic pathway (B) Uromic acid pathway (C) TCA cycle (D) HMP shunt
Description : Pentose production is increased in (A) HMP shunt (B) Uromic acid pathway (C) EM pathway (D) TCA cycle
Description : A carrier molecule in the citric acid cycle is (A) Acetyl-CoA (B) Citrate (C) Oxaloacetate (D) Malate
Description : During each cycle of on going fatty acid oxidation, all the following compounds are generated except (A) H2O (B) Acetyl CoA (C) Fatty acyl CoA (D) NADH FATS AND FATTY ACID METABOLISM 103
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
Description : Why is the Krebs cycle called the TCA cycle ?
Last Answer : The first acid produced in the Krebs cycle is citric acid. Since citric acid contains three carboxylic (- COOH) radicals , the Krebs-cycle is called the TCA cycle or tri-carboxylic acid cycle.
Description : TCA cycle starts with the condensation of acetyl group with (A) _____ (B)_____ to yield citric acid.
Last Answer : TCA cycle starts with the condensation of acetyl group with (A) _____ (B)_____ to yield citric acid.
Description : Which of these statements is incorrect? (a) Enzymes of TCA cycle are present in mitochondrial matrix. (b) Glycolysis occurs in cytosol. (c) Glycolysis operates as long as it is supplied ... that can pick up hydrogen atoms. (d) Oxidative phosphorylation takes place in outer mitochondrial membrane
Last Answer : (d) Oxidative phosphorylation takes place in outer mitochondrial membrane
Description : TCA cycle functions in A.catabolic reactions B.anabolic reactions C.amphibolic reactions D.none of these
Last Answer : C.amphibolic reactions
Description : Why the bacterium Treponemapallidum is difficult to culture? A-.Because it requires a great deal of water to reproduce B- .Because it is unable to use carbohydrates as an energy source ... TCA cycle and oxidative phosphorylation D- Because it requires extremely low temperature at which water freezes
Last Answer : Because it lacks the genes needed for TCA cycle and oxidative phosphorylation