Description : The condensation of 2 molecules of δ-aminolevulinate dehydratase contains (A) ALA synthase (B) ALA hydratase (C) Uroporphyrinogen synthase I (D) Uroporphyrinogen synthase III
Last Answer : Answer : B
Description : The enzyme involved in congenial erythropoietic porphyria is (A) Uroporphyrinogen I synthase (B) Uroporphyrinogen III cosynthase (C) Protoporphyrinogen oxidase (D) Ferrochelatase
Description : Conversion of the linear tetrapyrrole hydroxymethylbilane to uroporphyrinogen III (A) Occurs spontaneously (B) Catalysed by uroporphyrinogen I synthase (C) Catalysed by uroporphyrinogen III cosynthase (D) Catalysed by combined action of uroporphyrinogen I synthase and uroporphyrinogen III cosynthase
Last Answer : Answer : D
Description : Acute intermittent porphyria (paraoxymal porphyria) is caused due to deficiency of (A) Uroporphyrinogen I synthase (B) ALA synthase (C) Coproporphyrinogen oxidase (D) Uroporphyrinogen decarboxylase
Last Answer : Answer : A
Description : Protoporphyria (erythrohepatic) is characterized by the deficiency of (A) ALA synthase (B) ALA hydratase (C) Protophyrinogen oxidae (D) Ferrochelatase
Description : The synthesis of heme from protophyrin III is catalysed by the enzyme: (A) ALA synthase (B) Ferroreductase (C) Ferrooxidase (D) Ferrochelatase
Description : The enzyme involved in variegate porphyria is (A) Protoporphyrinogen oxidase (B) Coproporphyrinogen oxidase (C) Uroporphyrinogen decarboxylase (D) ALA decarboxylase
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
Description : The probable cause of porphyria cutanea tarda is deficiency of (A) Uroporphyrinogen oxidase (B) Coproporphyrinogen oxidase (C) Protoporphyrinogen oxidase (D) Uroporphyrinogen I synthase MINERAL METABOLISM 185
Description : In the biosynthesis of the iron protoporphyrin, the product of the condensation between succinyl-CoA and glycine is (A) α-Amino β-ketoadipic acid (B) δ-Aminolevulinate (C) Hydroxymethylbilane (D) Uroporphyrinogen I
Description : Conversion of uroporphyrinogen III to coprophyrinogen III is catalysed by the enzyme.: (A) Uroporphyrinogen decarboxylase (B) Coproporphyrinogen oxidase (C) Protoporphyrinogen oxidase (D) Ferrochelatase
Description : Hereditary coproporphyria is caused due to deficiency of (A) Protoporphyrinogen oxidase (B) ALA synthase (C) ALA dehydratase (D) Coproporphyrinogen oxidase
Description : Many xenobiotics (A) Increase hepatic ALA synthase (B) Decrease hepatic ALA sythase (C) Increase hepatic ALA dehydrase (D) Decrease hepatic ALA dehydrase
Description : Her’s disease is characterized by deficiency of (A) Muscle phosphorylase (B) Liver phosphorylase (C) Debranching enzyme (D) Glycogen synthase
Description : In which of the following types of enzyme water may be added to a C—C double bond without breaking the bond? (A) Hydrolase (B) Hydratase (C) Hydroxylase (D) Esterase
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
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
Description : The enzyme which can add water to a carbon-carbon double bond or remove water to create a double bond without breaking the bond is (A) Hydratase (B) Hydroxylase (C) Hydrolase (D) Esterase
Description : For Catecholamine biosynthesis the rate limiting enzyme is (A) DOPA decarboxylase (B) DOPAMINE β-hydroxylase (C) Tyrosine hydroxylase (D) Phenylalanine hydroxylase
Last Answer : Answer : C
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 : A regulator of the enzyme glucogen synthase is (A) Citric Acid (B) Pyruvate (C) Glucose-6-PO4 (D) GTP
Description : The protein, which is in fact a multifunctional enzyme complex in higher organism is (A) Acetyl transacylase (B) Malonyl transacylase (C) 3-Hydroxy acyl-ACP dehyratase (D) Fatty acid synthase
Description : Cori disease (Limit dextrinosis) is caused due to absence of (A) Branching enzyme (B) Debranching enzyme (C) Glycogen synthase (D) Phosphorylase
Description : In glycogenesis a branch point in the molecule is established by the enzyme (A) Amylo[1→ 4][1→ 6] transglucosidase (B) α [1→ 4] α [1→ 4] Glucan transferase (C) Amylo [1→ 6] glucosidase (D) Glycogen synthase
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 : A regulator of the enzyme Glycogen synthase is (A) Citric acid (B) 2, 3 bisphosphoglycerate (C) Pyruvate (D) GTP
Last Answer : C
Description : The biosynthesis of urea occurs mainly in the liver: (A) Cytosol (B) Mitochondria (C) Microsomes (D) Nuclei
Description : In the pathway leading to biosynthesis of acetoacetate from acetyl-CoA in liver, the immediate precursor of aceotacetate is (A) Acetoacetyl-CoA (B) 3-Hydroxybutyryl-CoA (C) 3-Hydroxy-3-methyl-glutaryl-CoA (D) 3-Hydroxybutyrate
Description : Urea biosynthesis occurs mainly in the liver involving the number of amino acids: (A) 3 (B) 4 (C) 5 (D) 6
Description : The biosynthesis of Urea occurs mainly in the Liver: (A) Cytosol (B) Microsomes (C) Nucleus (D) Mitochondria
Description : The regulatory enzyme for haem synthesis is (A) ALA synthetase (B) haem synthetase (C) Both (A) and (B) (D) None of these
Description : A cofactor required for the activity of the enzyme ALA dehydratase is (A) Cu (B) Mn (C) Mg (D) Fe
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 : An enzyme of pyrimidine nucleotides biosynthesis regulated at the genetic level by apparently coordinate repression and derepression is (A) Carbamoyl phosphate synthetase (B) Dihydroorotate dehydrogenase (C) Thymidine kinase (D) Deoxycytidine kinase
Description : An enzyme of pyrimidine nucleotide biosynthesis sensitive to allosteric regulation is (A) Aspartate transcarbamoylase (B) Dihydroorotase (C) Dihydroorotate dehydrogenase (D) Orotidylic acid decarboxylase
Description : In biosynthesis of cholesterol triparanol inhibits the activity of the enzyme: (A) ∆24 Reductase (B) Oxidosqualene-lanosterol cyclase (C) Isomerase (D) Squalene epoxidase ENZYMES 155
Description : The rate limiting step in cholesterol biosynthesis is one of the followings : (A) LDL-receptor concentration (B) VLDL secretion (C) Mevalonic acid formation (D) Co-enzyme A formation
Last Answer : (C) Mevalonic acid formation
Description : An allosteric enzyme responsible for controlling the rate of T.C.A cycle is (A) Malate dehydrogenase (B) Isocitrate dehydrogenase (C) Fumarase (D) Aconitase
Last Answer : B
Description : Chain elongation of fatty acids in mammalian liver occurs in (A) Nucleus (B) Ribosomes (C) Lysosomes (D) Microsomes
Description : The number of ATP molecules required to convert 2 molecules of lactate into glucose in mammalian liver is (A) 2 (B) 4 (C) 5 (D) 6
Description : Chain elongation of fatty acids occurring in mammalian liver takes place in which of the following subcellular fractions of the cell? (A) Nucleus (B) Ribosomes (C) Lysosomes (D) Microsomes
Description : Oxidative conversion of many amino acids to their corresponding -ketoacids occurs in mammalian: (A) Liver and kidney (B) Adipose tissue (C) Pancreas (D) Intestine
Description : Which of the following coenzyme is required for porphyrin synthesis? (A) Coenzyme A (B) Pyridoxal phosphate (C) Both (A) and (B) (D) None of these
Description : An amino acid required for porphyrin synthesis is (A) Proline (B) Glycine (C) Serine (D) Histidine
Description : The porphyrin present in haem is (A) Uroporphyrin (B) Protoporphyrin I (C) Coproporphyrin (D) Protoporphyrin II
Description : The number of molecules of porphobilinogen required for the formation of a tetrapyrrole i.e., a porphyrin is (A) 1 (B) 2 (C) 3 (D) 4
Description : Porphyrin synthesis is inhibited in (A) Mercury poisoning (B) Lead poisoning (C) Manganese poisoning (D) Barium poisoning
Description : In which of the following types of enzymes, water may be added to a C—C double bond without breaking the bond? (A) Hydrolase (B) Hydratase (C) Hydroxylase (D) Oxygenase
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