Description : Each of the following can be an intermediate in the synthesis of phosphatidyl choline except (A) Phosphatidyl inositol (B) CDP-choline (C) Phosphatidyl ethanolamine (D) Diacylglycerol
Last Answer : Answer : A
Description : Which one of the following compounds is a key intermediate in the synthesis of both triacyl glycerols and phospholipids? (A) CDP Choline (B) Phosphatidase (C) Triacyl glyceride (D) Phosphatidyl serine
Last Answer : Answer : B
Description : Following enzyme is involved in the synthesis of actylcholine (a) Choline acetyl transferase (b) Acetyl cholinesterase (c) Both (a) and (b) (d) None of the above
Last Answer : Ans: A
Description : Conversion of deoxyuridine monophosphate to thymidine monophosphate is catalysed by the enzyme: (A) Ribonucleotide reductase (B) Thymidylate synthetase (C) CTP synthetase (D) Orotidylic acid decarboxylase
Description : CTP synthetase forms CTP from (A) CDP and inorganic phosphate (B) CDP and ATP (C) UTP and glutamine (D) UTP and glutamate
Last Answer : Answer : C
Description : G-proteins have a nucleotide binding site for (A) ADP/ATP (B) GDP/GTP (C) CDP/CTP (D) UDP/UTP
Description : Second messenger for glucagons is (A) Cyclic AMP (B) Diacylglycerol (C) Cyclic GMP (D) Inositol triphosphate
Description : The second messenger for PTH is (A) Cyclic AMP (B) Cyclic GMP (C) Diacylglycerol (D) Inositol triphosphate
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 rate limiting step in catecholamine synthesis is catalysed by (A) Phenylalanine hydroxylase (B) Tyrosine hydroxylase (C) Dopa decarboxylase (D) Phenylethanolamine N-methyl transferase
Description : Galactose 1-phosphate is converted to uridine diphosphate galactose, the reaction is catalysed by the enzyme: (A) Glactokinase (B) Galactose 1-phosphate uridyl transferase (C) Uridine diphospho galactose 4-epimerase (D) UDP glucose pyrophosphorylase
Description : In the biosynthesis of cholesterol, the rate limiting enzyme is (A) Mevalonate kinase (B) HMG-CoA synthetase (C) HMG-CoA reductase (D) Cis-prenyl transferase
Description : Sphingomyelins on hydrolysis yields (A) Glycerol, fatty acids, phosphoric acid and choline (B) Glycerol, sphingosine, choline and fatty acids (C) Sphingosine, phosphoric acid, Glycerol and inositol (D) Sphingosine, fatty acids, phosphoric acid and choline
Last Answer : Answer : D
Description : Lecithin contains a nitrogenous base named as (A) Ethanolamine (B) Choline (C) Inositol (D) All of these
Description : Cephalin consists of (A) Glycerol, fatty acids, phosphoric acid and choline (B) Glycerol, fatty acids, phosphoric acid and ethanolamine (C) Glycerol, fatty acids, phosphoric acid and inositol (D) Glycerol, fatty acids, phosphoric acid and serine
Description : Which of the following phospholipids is localized to a greater extent in the outer leaflet of the membrane lipid bilayer? (A) Choline phosphoglycerides (B) Ethanolamine phosphoglycerides (C) Inositol phosphoglycerides (D) Serine phosphoglycerides
Last Answer : A
Description : Activated phospholipase C acts on (A) Phosphatidyl inositol-4, 5-biphosphate (B) Inositol-1, 4, 5-triphosphate (C) Protein kinase C (D) Pl-3 kinase
Description : Protein kinase C is activated by (A) Cyclic AMP (B) Cyclic GMP (C) Diacyl glycerol (D) Inositol triphosphate
Description : LCAT is (A) Lactose choline alamine transferse (B) Lecithin cholesterol acyl transferase (C) Lecithin carnitine acyl transferase (D) Lanoleate carbamoyl acyl transferase
Description : The synthesis of heme from protophyrin III is catalysed by the enzyme: (A) ALA synthase (B) Ferroreductase (C) Ferrooxidase (D) Ferrochelatase
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 : De novo synthesis of fatty acids is catalysed by a multi-enzyme complex which contains (A) One-SH group (B) Two-SH groups (C) Three-SH groups (D) Four-SH groups
Description : Methotrexate blocks the synthesis of thymidine monophosphate by inhibiting the activity of the enzyme: (A) Dihydrofolate reductase (B) Orotate phosphoribosyl transferase (C) Ribonucleotide reductase (D) Dihydroorotase
Description : The enzyme regulating extramitochondrial fatty acid synthesis is (A) Thioesterase (B) Acetyl CoA carboxylase (C) Acyl transferase (D) Multi-enzyme complex
Description : Synthesis of polyunsaturated fatty acids involves the enzyme systems: (A) Acyl transferase and hydratase (B) Desaturase and elongase (C) Ketoacyl-CoA reductase and hydratase (D) Dihydroxyacetone phosphate
Last Answer : (A) Choline phosphoglycerides
Description : The ability of CTP to bind to aspartate carbamoyltransferase and shut down the synthesis of more A- enzyme induction B- enzyme repression C- feedback inhibition of enzyme activity D- none of these
Last Answer : feedback inhibition of enzyme activity
Description : The α-amino group of the new amino acyl tRNA in the A site carries out a nucleophilic attack on the esterified carboxyl group of the peptidyl tRNA occupying the P site. This reaction is catalysed by (A) DNA polymerase (B) RNA polymerase (C) Peptidyl transferase (D) DNA ligase
Description : Conversion of inosine monophosphate to xanthine monophosphate is catalysed by (A) IMP dehydrogenase (B) Formyl transferase (C) Xanthine-guanine phosphoribosyl transferase (D) Adenine phosphoribosyl transferase
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 : Which of the following concerning the conjugation of bilirubin is correct? 1) is catalysed by a glucuronyl transferase 2) occurs in the Kupfer cells of the liver 3) is increased by valproate 4) is inhibited by rifampicin 5) is impaired in Dubin-Johnson syndrome
Last Answer : Answers-1 b - Hepatocytes. c - Enzyme inhibitor. d - Enzyme inducer. e - Conjugation is OK but excretion from the hepatocyte into the bile is impaired. (Gilbert's syndrome ... bilirubinaemia. Dubin-Johnson syndrome - bilirubin can't Depart from the hepatocyte - conjugated bilirubinaemia.)
Description : Phosphorylation of adenosine to AMP is catalysed by (A) Adenosine kinase (B) Deoxycytidine kinase (C) Adenylosuccinase (D) Adenylosuccinate synthetase
Description : HMG-CoA is converted to mevalonate by reduction catalysed by (A) HMG-CoA synthetase (B) HMG-CoA reductase (C) Mevalonate kinase (D) Thiolase
Description : Two molecules of acetyl-CoA condense to form acetoacetyl-CoA catalysed by (A) Thiolase (B) Kinase (C) Reductase (D) Isomerase
Description : Transfer of the carbamoyl moiety of carbamoyl phosphate to ornithine is catalysed by a liver mitochondrial enzyme: (A) Carbamoyl phosphate synthetase (B) Ornithine transcarbamoylase (C) N-acetyl glutamate synthetase (D) N-acetyl glutamate hydrolase
Description : Glycerol-3-phosphate for the synthesis of triglycerides in adipose tissue is derived from (A) Phosphatidic acid (B) Diacylglycerol (C) Glycerol (D) Glucose
Description : Intermediate in the denovo synthesis of triacyl glycerols include all the following except (A) Fatty acyl CoA (B) CDP diacyl glycerol (C) Glycerol-3-phosphate (D) Lysophosphatidic acid
Description : The following are true about acetylcholine: a. it is synthesized from acetyl-coenzyme A and choline b. its formation is catalysed by acetylcholinesterase c. at the synaptic cleft, ... inactivated by hydrolysis d. reuptake by the presynaptic neurones play an important in inactivating acetylcholine
Last Answer : at the synaptic cleft, it is inactivated by hydrolysis
Description : The mRNA ready for protein synthesis has the ________ cap. (A) ATP (B) CTP (C) GTP (D) UTP
Description : For synthesis of CTP and UTP, the amino group comes from (A) Amide group of Asparagine (B) Amide group of glutamine (C) α-Amino group of glutamine (D) α-Amino group of glutamate
Description : The first pyrimidine nucleotide to be formed in de novo synthesis pathway is (A) UMP (B) CMP (C) CTP (D) TMP
Description : Coenzymes derived from the vitamin shown below are required by enzymes involved in the synthesis of which of the following? (A) ATP (B) UTP (C) CTP (D) NADH
Description : CTP is required for the synthesis of (A) Fatty acids (B) Proteins (C) Phospholipids (D) Cholesterol
Description : The rate limiting enzyme in the synthesis of catecholamines is: A. Tyrosine hydroxylase B. Dopa decarboxylase C. Dopamine β-hydroxylase D. Noradrenaline N-methyl transferase
Last Answer : A. Tyrosine hydroxylase
Description : In plants, enzyme responsible for the synthesis of the malic acid is : (A) Rubisco (B) PEP carboxylase (C)Kinase (D) Urease
Last Answer : (A) Rubisco
Description : In the biosynthesis of c-DNA, the joining enzyme ligase requires (A) GTP (B) ATP (C) CTP (D) UTP
Description : The enzyme aspartate transcarbamoylase of pyrimidine biosynthesis is inhibited by (A) ATP (B) ADP (C) AMP (D) CTP
Description : The enzyme -ketoglutarate dehydrogenase in the citric acid cycle requires (A) Lipoate (B) Folate (C) Pyridoxine (D) Inositol
Description : In mammals, synthesis of mRNA is catalysed by (A) RNA polymerase I (B) RNA polymerase II (C) RNA polymerase III(D) RNA polymerase IV