Description : The major determinant of the overall rate of denovo purine nucleotide biosynthesis is the concentration of (A) 5-phosphoribosyl 1-pyrophosphate (B) 5-phospho β-D-ribosylamine (C) Glycinamide ribosyl-5-phosphate (D) Formylglycinamide ribosyl-5-phosphate
Last Answer : Answer : A
Description : Conversion of formylglycinamide ribosyl5-phosphate to formyl-glycinamide ribosyl-5-phosphate is inhibited by (A) Azaserine (B) Diazonorleucine (C) 6-Mercaptopurine (D) Mycophenolic acid
Description : Ring closure of formimidoimidazole carboxamide ribosyl-5-phosphate yields the first purine nucleotide: (A) AMP (B) IMP (C) XMP (D) GMP
Last Answer : Answer : B
Description : 6-Mercapto purine inhibits the conversion of (A) IMP→ XMP (B) Ribose 5 phosphate → PRPP (C) PRPP → 5-phospho →β -D-ribosylamine (D) Glycinamide ribosyl 5-phosphate → formylglycinamide ribosyl-5-phosphate
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 : The first reaction unique to purine nucleotide synthesis is catalysed by (A) PRPP synthetase (B) PRPP glutamyl amido transferase (C) Phosphoribosyl glycinamide synthetase (D) Formyl transferase
Description : The cofactors required for synthesis of adenylosuccinate are (A) ATP, Mg++ (B) ADP (C) GTP, Mg++ (D) GDP
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
Description : Conversion of tyrosine to dihydroxyphenylalanine is catalysed by tyrosine hydroxylase which requires (A) NAD (B) FAD (C) ATP (D) Tetrahydrobiopterin
Description : An enzyme which acts as allosteric regulator and sensitive to both phosphate concentration and to the purine nucleotides is (A) PRPP synthetase (B) PRPP glutamyl midotransferase (C) HGPR Tase (D) Formyl transferase
Description : UDPG is oxidized to UDP glucuronic acid by UDP dehydrogenase in presence of (A) FAD+ (B) NAD+ (C) NADP+ (D) ADP+
Last Answer : B
Description : The enzyme aspartate transcarbamoylase of pyrimidine biosynthesis is inhibited by (A) ATP (B) ADP (C) AMP (D) CTP
Description : What molecule as a phosphate group to ADP to make ATP?
Last Answer : Need answer
Description : The most abundant free nucleotide in mammalian cells is (A) ATP (B) NAD (C) GTP (D) FAD
Description : Magnesium ions are required in the reactions involving (A) NAD (B) FAD (C) ATP (D) CoA
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 : The transaminase activity needs the coenzyme: (A) ATP (B) B6 – PO4 (C) FAD+ (D) NAD+
Description : Sulphur containing coenzyme is (A) NAD (B) FAD (C) Pyridoxal phosphate (D) Biotin
Description : Vitamin B2 is component of coenzyme: (A) Pyridoxal phosphate (B) TPP (C) NAD (D) FMN/FAD
Description : The hydrogen acceptor used in pentose phosphate pathway is (A) NAD (B) NADP (C) FAD (D) FMN
Description : For synthesis of sphingosine, all the following coenzymes are required except (A) Pyridoxal phosphate (B) NADPH (C) FAD (D) NAD
Description : DNA ligase of E. coli requires which of the following co-factors? (A) FAD (B) NAD+ (C) NADP+ (D) NADH
Description : Decarboxylation of α-keto acids requires (A) Thiamine pyrophosphate, FAD, NAD+ (B) Flavin mononucleotide (C) NADP+ (D) NAD+ only
Description : For reduction enzyme HMG-CoA reductase requires cofactor: (A) NADPH (B) NADP (C) NAD (D) FAD
Description : UDP glucose is converted to UDP glucurronate, a reaction catalysed by UDP glucose dehydrogenase requires (A) NAD+ (B) FAD (C) NADP (D) FMN
Description : Mitochondrial α-ketoglutarate dehydrogenase complex requires all the following to function except (A) CoA (B) FAD (C) NAD+ (D) NADP+
Description : β-Oxidation of fatty acids requires all the following coenzymes except (A) CoA (B) FAD (C) NAD (D) NADP
Description : A key substance in the committed step of pyrimidines biosynthesis is (A) Ribose-5-phosphate (B) Carbamoyl phosphate (C) ATP (D) Glutamine
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 : 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 : Synthesis of glutamine is accompanied by the hydrolysis of (A) ATP (B) ADP (C) TPP (D) Creatin phosphate
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 : 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 : Pyrimidine biosynthesis begins with the formation from glutamine, ATP and CO2, of (A) Carbamoyl aspartate (B) Orotate (C) Carbamoyl phosphate (D) Dihydroorotate
Description : All of the following statements about thioredoxin reductase are true except: (A) It requires NADH as a coenzyme (B) Its substrates are ADP, GDP, CDP and UDP (C) It is activated by ATP (D) It is inhibited by dADP
Description : The enzyme phosphoenolpyruvate carboxykinase catalyses the conversion of oxaloacetate to phosphoenolpyruvate requires (A) ATP (B) ADP (C) AMP (D) GTP
Description : In the biosynthesis of c-DNA, the joining enzyme ligase requires (A) GTP (B) ATP (C) CTP (D) UTP
Description : N10-formyl and N5N10-methenyl tetrahydrofolate contributes purine carbon atoms at position (A) 4 and 6 (B) 4 and 5 (C) 5 and 6 (D) 2 and 8
Description : A coenzyme required for the synthesis of glycine from serine is (A) ATP (B) Pyridoxal phosphate (C) Tetrahydrofolate (D) NAD
Description : Synthesis of GMP and IMP requires the following: (A) NH3 NAD+, ATP (B) Glutamine, NAD+, ATP (C) NH3, GTP, NADP+ (D) Glutamine, GTP, NADP+
Description : Synthesis of sphingosine requires the cofactor (A) NAD (B) NADP (C) NADPH+ (D) ATP
Description : A coenzyme containing non aromatic hetero ring is (A) ATP (B) NAD (C) FMN (D) Biotin
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 : 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.
Description : The pathway of glycogen biosynthesis involves a special nucleotide of glucose. In the reaction below, NuDP stands for NuDP Glucose + glycogenn → NuDP + glycogenn+1 (A) ADP (B) GDP (C) UDP (D) CDP
Description : In purine biosynthesis carbon atoms at 4 and 5 position and N at 7 position are contributed by (A) Glycine (B) Glutamine (C) Alanine (D) Threonine
Description : When one glucose molecule is completely oxidised, it changes (a) 36 ADP molecules into 36 ATP molecules (b) 38 ADP molecules into 38 ATP molecules (c) 30 ADP molecules into 30 ATP molecules (d) 32 ADP molecules into 32 ATP molecules.
Last Answer : (b) 38 ADP molecules into 38 ATP molecules
Description : In glycolysis, during oxidation electrons are removed by (a) ATP (b) glyceraldehyde-3-phosphate (c) NAD+ (d) molecular oxygen.
Last Answer : (c) NAD+
Description : Pyrimidine and purine nucleoside biosynthesis share a common precursor: (A) PRPP (B) Glycine (C) Fumarate (D) Alanine
Description : Purine biosynthesis is inhibited by (A) Aminopterin (B) Tetracyclin (C) Methotrexate (D) Chloramphenicol