Description : The cyclooxygenase isoenzymes COX-1 and COX-2 differ from each other in that (a) They catalyse different pathways in prostanoid biosynthesis (b) COX–1 is inhibited by aspirin but not COX–2 (c) COX–2 is inhibited by ibuprofen but not COX–1 (d) COX–1 is constitutive while COX–2 is inducible
Last Answer : Ans: D
Description : The cyclooxygenase isoenzymes COX-1 and COX-2 differ from each other in that: A. They catalyse different pathways in prostanoid biosynthesis B. COX-1 is inhibited by aspirin but not COX-2 C. COX-2 is inhibited by ibuprofen but not COX-1 D. COX-1 is constitutive while COX-2 is largely
Last Answer : D. COX-1 is constitutive while COX-2 is largely
Description : What are the pathways stimulated by insulin?
Last Answer : Glycolysis, glycogen synthesis, HMP shunt pathway, lipogenesis.
Description : Action of glycogen synthase is inhibited by (A) Insulin (B) Glucose (C) Mg2+ (D) Cyclic AMP
Last Answer : Answer : C
Description : The synthesis of glucose from pyruvate by gluconeogenesis (A) Requires the participation of biotin (B) Occurs exclusively in the cytosol (C) Is inhibited by elevated level of insulin (D) Requires oxidation/reduction of FAD
Last Answer : A
Description : What are the important enzymes inhibited by insulin?
Last Answer : Glucose-6-phosphatase, glycogen phosphorylase, hormone sensitive lipase.
Description : Insulin secretion: a. is inhibited by atropine b. is increased by vagal stimulation c. is inhibited by amino acids d. is stimulated by beta agonists
Last Answer : is increased by vagal stimulation
Description : A metabolic pathways is a (A) Route taken by chemicals (B) Sequence of enzyme facilitated chemical reactions (C) Route taken by an enzyme from one reaction to another (D) Sequence of origin of organic molecules
Last Answer : Answer : B
Description : In most metabolic pathways, all needed enzymes are arranged together in a multienzyme complex within a (A) Solution of ATP (B) Membrane (C) Quanternary protein (D) Coenzyme
Description : Most major metabolic pathways are considered mainly either anabolic or catabolic. Which of the following pathway is most correctly considered to be amphibolic? (A) Citric acid cycle (B) Gluconeogenesis (C) Lipolysis (D) Glycolysis
Last Answer : Answer : A
Description : A metabolite which is common to pathways of cholesterol biosynthesis from acetyl-CoA and cholecalciferol formation from cholesterol is (A) Zymosterol (B) Lumisterol (C) Ergosterol (D) 7 Dehydrocholesterol
Last Answer : Answer : D
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
Last Answer : D
Description : What reductive biosynthesis pathways need NADPH?
Last Answer : Fatty acid biosynthesis, synthesis of cholesterol, steroid hormones.
Description : The binding of prokaryotic DNA dependent RNA polymerase to promoter sits of genes is inhibited by the antibiotic: (A) Streptomycin (B) Rifamcin (C) Aueromycin (D) Puromycin
Description : Cancer cells may become resistant to amethopterin by (A) Developing mechanisms to destroy amethopterin (B) Amplification of dihydrofolate reducatse gene (C) Mutation in the dihydrofolate reductase ... is no longer inhibited by amethopterin (D) Developing alternate pathway of thymidylate synthesis
Description : Mitochondrial protein synthesis is inhibited by (A) Cycloheximide (B) Chloramphenicol (C) Diptheria toxin (D) None of these
Description : The regulatory i gene of lac operon (A) Is inhibited by lacotse (B) Is inhibited by its own product, the repressor protein (C) Forms a regulatory protein which increases the expression of downstream structural genes (D) Is constitutively expressed
Description : Peptidyl transferase activity of 50 S ribosomal subunits is inhibited by (A) Rifampicin (B) Cycloheximide (C) Chloramphenicol (D) Erythromycin
Description : Binding of formylmehtionyl tRNA to 30 S ribosomal subunit of prokaryotes is inhibited by (A) Streptomycin (B) Chloramphenicol (C) Erythromycin (D) Mitomycin
Description : Aspartate transcarbamoylase is inhibited by (A) CTP (B) PRPP (C) ATP (D) TMP
Description : Cytosolic carbamoyl phosphate synthetase is inhibited by (A) UTP (B) CTP (C) PRPP (D) TMP
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 : PRPP synthetase is allosterically inhibited by (A) AMP (B) ADP (C) GMP (D) All of these
Description : The binding of prokaryotic DNA dependent RNA polymerase to promoter sites of genes is inhibited by the antibiotic: (A) Puromycin (B) Rifamycin (C) Terramycin (D) Streptomycin
Description : The enzyme aspartate transcarbamoylase of pyrimidine biosynthesis is inhibited by (A) ATP (B) ADP (C) AMP (D) CTP
Description : Purine biosynthesis is inhibited by (A) Aminopterin (B) Tetracyclin (C) Methotrexate (D) Chloramphenicol
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 : PRPP glutamyl amidotransferase, the first enzyme uniquely committed to purine synthesis is feed back inhibited by (A) AMP (B) IMP (C) XMP (D) CMP
Description : Tyrosine hydroxylase is inhibited by (A) Catecholamines (B) α−Methyldopa (C) Phenylalanine (D) Vanillyl mandelic acid
Description : Dopa decarboxylase is inhibited by (A) Epinephrine (B) Norepinephrine (C) α−Methyldopa (D) None of these
Description : In males, secretion of luteinising hormone is inhibited by (A) Gonadotropin releasing hormone (B) FSH (C) High blood level of testosterone (D) Inhibin
Description : All the following statements about thyrotropin releasing hormone are true except (A) It is secreted by hypothalamus (B) It is a pentapeptide (C) It increases the secretion of TSH (D) Its secretion is inhibited by high level of T3 and T4 in blood
Description : Secretion of growth hormone is inhibited by (A) Somatomedin C (B) Somatostatin (C) Feedback inhibition(D) All of these
Description : Porphyrin synthesis is inhibited in (A) Mercury poisoning (B) Lead poisoning (C) Manganese poisoning (D) Barium poisoning
Description : Transfer of reducing equivalents from succinate dehydrogenase to coenzyme Q is specifically inhibited by (A) Carboxin (B) Oligomycin (C) Piericidin A (D) Rotenone
Description : Activity of cytochrome oxidase is inhibited by (A) Sulphite (B) Sulphate (C) Arsenite (D) Cyanide
Description : In which of the following types of enzymes an inducer is not required? (A) Inhibited enzyme (B) Cooperative enzyme (C) Allosteric enzyme (D) Constitutive enzyme
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 : Phosphofructokinase is allosterically inhibited by (A) Fructose-1, 6-biphosphate (B) Lactate (C) Pyruvate (D) Citrate
Description : Isocitrate dehydrogenase is allosterically inhibited by (A) Oxalosuccinate (B) α-Ketoglutarate (C) ATP (D) NADH
Description : Carbonic anhydrase is competitively inhibited by (A) Allopurinol (B) Acetazolamide (C) Aminopterin (D) Neostigmine
Description : An allosteric enzyme is generally inhibited by (A) Initial substrate of the pathway (B) Substrate analogues (C) Product of the reaction catalysed by allosteric enzyme (D) Product of the pathway
Description : The activity of HMG-CoA reductase is inhibited by (A) A fungal inhibitor mevastatin (B) Probucol (C) Nicotinic acid (D) Clofibrate
Description : Formation of succinyl-CoA from α-Ketoglutarate is inhibited by (A) Fluoroacetate (B) Arsenite (C) Fluoride (D) Iodoacetate
Description : Pyruvate dehydrogenase activity is inhibited by (A) Mercury (B) Zinc (C) Calcium (D) Sodium
Description : Hexokinase is inhibited in an allosteric manner by (A) Glucose-6-Phosphate (B) Glucose-1-Phosphate (C) Fructose-6-phosphate (D) Fructose-1, 6-biphosphate
Description : Phosphofructokinase key enzyme in glycolysis is inhibited by (A) Citrate and ATP (B) AMP (C) ADP (D) TMP
Description : A demonstrable inducer is absent in (A) Allosteric enzyme (B) Constitutive enzyme (C) Inhibited enzyme (D) Co-operative enzyme ENZYMES 141
Description : Synthesis of prostaglandins is inhibited by (A) Glucocorticoids (B) Aspirin (C) Indomethacin (D) All of these