Description : The rate limiting reaction in the lipogenic pathway is (A) Acetyl-CoA carboxylase step (B) Ketoacyl synthase step (C) Ketoacyl reductase step (D) Hydratase step
Last Answer : Answer : A
Description : Acetyl-CoA is the principal building block of fatty acids. It is produced within the mitochondria and does not diffuse readily into cytosol. The availability of acetyl CoA involves (A) Carnitine acyl transferase (B) Pyruvate dehydrogenase (C) Citrate lyase (D) Thiolase
Last Answer : Answer : C
Description : The enzyme regulating extramitochondrial fatty acid synthesis is (A) Thioesterase (B) Acetyl CoA carboxylase (C) Acyl transferase (D) Multi-enzyme complex
Last Answer : Answer : B
Description : In β-oxidation 3-ketoacyl-CoA is splitted at the 2, 3 position by the enzyme: (A) Hydratase (B) Dehydrogenase (C) Reducatse (D) Thiolase
Last Answer : Answer : D
Description : Insulin regulates fatty acid synthesis by (A) Dephosphorylating of acetyl CoA carboxylase (B) Activating phosphorylase (C) Inhibiting malonyl CoA formation (D) Controlling carnitine-Acyl CoA transferase activity
Description : Acetyl CoA required for extra mitochondrial fatty acid synthesis is produced by (A) Pyruvate dehydrogenase complex (B) Citrate lyase (C) Thiolase (D) Carnitine-acyl transferase
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 carbon chain of fatty acids is shortened by 2 carbon atoms at a time. This involves successive reactions catalysed by 4-enzymes. These act the following order: (A) Acetyl CoA dehydrogenase, ... CoA dehydrogenase (D) Enoyl hydrase, β-OH acyl CoA dehydrogenase, acyl CoA dehydrogenase, thiolose,
Description : Fatty acids are activated to acyl CoA by the enzyme thiokinase: (A) NAD+ (B) NADP+ (C) CoA (D) FAD+
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 : Propionyl CoA is formed on oxidation of (A) Monounsaturated fatty acids (B) Polyunsaturated fatty acids (C) Fatty acids with odd number of carbon atoms (D) None of these FATS AND FATTY ACID METABOLISM 83
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 : 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
Description : In synthesis of Triglyceride from α-Glycero phosphate and acetyl CoA, the first intermediate formed is (A) β-diacyl glycerol (B) Acyl carnitine (C) Monoacyl glycerol(D) Phosphatidic acid
Description : Long chain fatty acids are first activated to acyl CoA in the (A) Cytosol (B) Mitochodria (C) Ribosomes (D) Microsome
Description : Long chain fatty acids penetrate the inner mitochondrial membrane (A) Freely (B) As acyl-CoA derivative (C) As carnitine derivative (D) Requiring Na dependent carrier
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
Description : The enzyme acyl-CoA synthase catalyses the conversion of a fatty acid of an active fatty acid in the presence of (A) AMP (B) ADP (C) ATP (D) GTP
Description : An enzyme required for the synthesis of ketone bodies as well as cholesterol is (A) Acetyl CoA carboxylase (B) HMG CoA synthetase (C) HMG CoA reductase (D) HMG CoA lyase
Description : Which one of the following enzymes requires a coenzyme derived from the vitamin whose structure is shown below? (A) Enoyl CoA hydratase (B) Phosphofructokinase (C) Glucose-6-phosphatase (D) Glucose-6-phosphate dehydrogenase
Description : Human desaturase enzyme system cannot introduce a double bond in a fatty acid beyond (A) Carbon 9 (B) Carbon 6 (C) Carbon 5 (D) Carbon 3
Description : In adipose tissue, glycerol-3-phosphate required for the synthesis of triglycerides comes mainly from (A) Hydrolysis of pre-existing triglycerides (B) Hydrolysis of phospholipids (C) Dihydroxyacetone phosphate formed in glycolysis (D) Free glycerol
Description : Fatty acids can not be converted into carbohydrates in the body, as the following reaction is not possible: (A) Conversion of glucose-6-phosphate into glucose (B) Fructose 1, 6 diphosphate to ... phosphate (C) Transformation of acetyl CoA to pyruvate (D) Formation of acetyl CoA from fatty acids
Description : Fatty acids cannot be converted into carbohydrates in the body as the following reaction is not possible. (A) Conversion of glucose-6-phosphate into glucose (B) Fructose 1,6-bisphosphate to fructose- ... (C) Transformation of acetyl CoA to pyruvate (D) Formation of acetyl CoA from fatty acids
Last Answer : C
Description : The enzyme amino acyl tRNA synthetase is involved in (A) Dissociation of discharged tRNA from 80S ribosome (B) Charging of tRNA with specific amino acids (C) Termination of protein synthesis (D) Nucleophilic attack on esterified carboxyl group of peptidyl tRNA
Description : All the following statements about acetyl CoA carboxylase are true except (A) It is required for de novo synthesis of fatty acids (B) It is required for mitochondrial elongation of fatty acids ( ... for microsomal elongation of fatty acids (D) Insulin converts its inactive form into its active form
Description : Formation of acetyl CoA from pyruvate for de novo synthesis of fatty acids requires (A) Pyruvate dehydrogenase complex (B) Citrate synthetase (C) ATP citrate lyase (D) All of these
Description : Acetyl CoA required for de novo synthesis of fatty acids is obtained from (A) Breakdown of existing fatty acids (B) Ketone bodies (C) Acetate (D) Pyruvate
Description : In the extra mitochondrial synthesis of fatty acids, CO2 is utilized (A) To keep the system anaerobic and prevent regeneration of acetyl CoA (B) In the conversion of malonyl to CoA hydroxybutyryl CoA (C ... of acetyl CoA to malonyl CoA (D) In the formation of acetyl CoA from 1 carbon intermediates
Description : A soluble system for synthesis of fatty acids have been isolated from avian liver, required for the formation of long chain fatty acids by this system is (A) ATP (B) Acetyl CoA (C) NADPH (D) All of these
Description : De novo synthesis and oxidation of fatty acids differ in the following respect: (A) Synthesis occurs in cytosol and oxidation in mitochondria (B) Synthesis is decreased and oxidation increased by ... synthesis and FAD in oxidation (D) Malonyl CoA is formed during oxidation but not during synthesis
Description : Acetyl CoA formed from pyruvate can be used for the synthesis of all the following except (A) Glucose (B) Fatty acids (C) Cholesterol (D) Steroid hormones
Description : Acetyl CoA from mitochondria is transferred to cytoplasm for the de novo synthesis of fatty acid, by which enzyme?
Last Answer : ATP citrate lyase.
Description : In the biosynthesis of triglycerides from glycerol 3-phosphate and acyl-CoA, the first intermediate formed is (A) 2-Monoacylglycerol (B) 1, 2-Diacylglycerol (C) Lysophosphatidic acid (D) Phosphatidic acid
Description : This catalyzes formation of CoA derivatives from fatty acid, CoA and ATP: (A) Acyl CoA dehydrogenase (B) Enoyl hydrase (C) β-OH acyl CoA dehydrogenase (D) Thio kinase
Description : Both Acyl carrier protein (ACP) of fatty acid synthetase and coenzyme (CoA) are (A) Contain reactive phosphorylated (B) Contain thymidine (C) Contain phosphopantetheine reactive groups (D) Contain cystine reactive groups
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 : Long chain fatty acyl CoA esters are transported across the mitochondrial membrane by (A) cAMP (B) Prostaglandin (C) Carnitine (D) Choline
Description : Vitamin E protects the polyunsaturated fatty acids from oxidation by molecular oxygen in the formation of (A) Superoxide (B) Peroxide (C) Trioxide (D) All of these
Description : Vitamin E protects (A) Polyunsaturated fatty acids against aperoxidation (B) Vitamin A and carotenes against oxidation (C) Lung tissue against atmospheric pollutants (D) All of these
Description : The desaturation and chain elongation system of polyunsaturated fatty acids are greatly diminished in the absence of (A) Insulin (B) Glycagon (C) Epinephrine (D) Thyroxine
Description : Oils having more than 50 % polyunsaturated fatty acids include all of the following except (A) Groundnut oil (B) Soyabean oil (C) Sunflower oil (D) Safflower oil
Description : Predominant fatty acids in meat are (A) Saturated (B) Monounsaturated (C) Polyunsaturated (D) Mono and poly-unsaturated
Description : Fluidity of membranes is increased by the following constituent except (A) Polyunsaturated fatty acids (B) Saturated fatty acids (C) Integral proteins (D) Cholesterol
Description : Diets having a high ratio of polyunsaturated: saturated fatty acids can cause (A) Increase in serum triglycerides (B) Decrease in serum cholesterol (C) Decrease in serum HDL (D) Skin lesions
Description : Which of the following can be oxidized by β-oxidation pathway? (A) Saturated fatty acids (B) Monosaturated fatty acids (C) Polyunsaturated fatty acids (D) All of these
Description : The percentage of polyunsaturated fatty acids in butter is (A) 60 (B) 37 (C) 25 (D) 3
Description : The percentage of polyunsaturated fatty acids in soyabean oil is (A) 62 (B) 10 (C) 3 (D) 2
Description : Animal fat is in general (A) Poor in saturated and rich in polyunsaturated fatty acids (B) Rich in saturated and poor in polyunsaturated fatty acids (C) Rich in saturated and polyunsaturated fatty acids (D) Poor in saturated and polyunsaturated fatty acids
Last Answer : B