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
Last Answer : Answer : B
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
Last Answer : Answer : A
Description : Microsomal hydroxylase system contains a (A) Di-oxygenase (B) Mono-oxygenase (C) Both (A) and (B) (D) None of thse
Description : β-Carotene, precursor of vitamin A, is oxidatively cleaved by (A) β-Carotene dioxygenase (B) Oxygenase (C) Hydroxylase (D) Transferase
Description : Neonatal tyrosinemia is due to deficiency of the enzyme: (A) p-Hydroxyphenylpyruvate hydroxylase (B) Fumarylacetoacetate hydrolase (C) Phenylalanine hydroxylase (D) Tyrosine dehydrogenase
Description : Alkaptonuria occurs due to deficiency of the enzyme: (A) Maleylacetoacetate isomerase (B) Homogentisate oxidase (C) p-Hydroxyphenylpyruvate hydroxylase (D) Fumarylacetoacetate hydrolase
Description : Tyrosinosis is due to defect in the enzyme: (A) Fumarylacetoacetate hydrolase (B) p-Hydroxyphenylpyruvate hydroxylase (C) Tyrosine transaminase (D) Tyrosine hydroxylase
Description : Richner-Hanhart syndrome is due to defect in (A) Tyrosinase (B) Phenylalanine hydroxylase (C) Hepatic tyrosine transaminase (D) Fumarylacetoacetate hydrolase
Description : β-Carotene, precursor of vitamin A, is oxidatively cleaved by (A) β-Carotene dioxygenase (B) Oxygenase \ (C) Hydroxylase (D) Transferase
Last Answer : (A) β-Carotene dioxygenase
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
Last Answer : Answer : D
Description : Which enzyme will add water to a double bond, without breaking the bond?
Last Answer : Hydratase.
Description : The salivary hydrolase is known as salivary amylase, or ptyalin. Ptyalin digests carbohydrates breaking starch and glycogen, glucose polymers, into maltose (a glucose disaccharide) and dextrin.
Last Answer : Why doesn't the food enter the trachea instead of going to the esophagus?
Description : In the biosynthesis of cortiol, the sequence of enzymes involved is (A) Hydroxylase–dehydrogenase + isomerase – hydroxylase (B) Dehydrogenase–hydroxylase–isomerase (C) Hydroxylase–lyase–dehydrogenase isomerase (D) Isomerase–lyase–hydroxylase–dehydrogenase
Description : ω-oxidation is normally a very minor pathway and is brought by hydroxylase enzymes involving (A) Cytochrome a (B) Cytochrome b (C) Cytochrome c (D) Cytochrome p-450
Last Answer : Answer : C
Description : Protoporphyria (erythrohepatic) is characterized by the deficiency of (A) ALA synthase (B) ALA hydratase (C) Protophyrinogen oxidae (D) Ferrochelatase
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
Description : In mammalian liver the rate controlling enzyme in porphyrin biosynthesis is (A) ALA synthase (B) ALA hydratase (C) Uroporphyrinogen I synthase (D) Uroporphyrinogen III cosynthase
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 : 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 : 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 catalyzing conversion of androstenedione to testosterone is a (A) Oxygenase (B) Dehydrogenase (C) Isomerase (D) Decarboxylase
Description : Isocitrate dehydrogenases is (A) Aerobic dehydrogenase (B) Anaerobic dehydrogenase (C) Hydroperoxidase (D) Oxygenase
Description : Name the enzyme that acts both as carboxylase at one time and oxygenase at another time. (A) PEP carboxylase (B) RuBP carboxylase (C) Carbonic anyhdrase (D) None of these
Description : Tryptophan pyrolase is currently known as (A) Tryptophan deaminase (B) Tryptophan dioxygenase (C) Tryptophan mono oxygenase (D) Tryptophan decarboxylase
Description : An enzyme which uses hydrogen acceptor as substrate is (A) Xanthine oxidase (B) Aldehyde oxidase (C) Catalase (D) Tryptophan oxygenase
Description : Cyclo-oxygenase is involved in the synthesis of (A) Prostaglandins (B) Thromboxanes (C) Both (A) and (B) (D) None of these
Description : Anti-inflammatory corticosteroids inhibit (A) Phospholipase A1 (B) Phospholipase A2 (C) Cyclo-oxygenase (D) Lipo-oxygenase
Description : Phenylbutazone and indomethacin inhibit (A) Phospholipase A1 (B) Phospholipase A2 (C) Cyclo-oxygenase (D) Lipo-oxygenase
Description : Prostaglandins are inactivated by (A) 15-Hydroxyprostaglandin dehydrogenase (B) Cyclo-oxygenase (C) Lipo-oxygenase (D) None of these
Description : Lipo-oxygenase is required for the synthesis of (A) Prostaglandins (B) Leukotrienes (C) Thromboxanes (D) All of these
Description : Which enzyme is concerned with transfer of electrons? (A) Desmolase (B) Hydrolase (C) Dehydrogenase (D) Transaminase
Description : Urease is a (A) Lyase (B) Ligase (C) Isomerase (D) Hydrolase
Description : The decarboxylation reaction in HMP shunt is catalysed by (A) Gluconolactone hydrolase (B) 6-Phosphogluconate dehydrogenase (C) 6-Phosphogluconate decarboxylase (D) Transaldolase
Description : The enzyme hexokinase is a (A) Hydrolase (B) Oxidoreductase (C) Transferase (D) Ligase
Description : Wolman’s disease is due to deficiency of (A) Cholesteryl ester hydrolase (B) Hexosaminidase A (C) α-Fucosidase (D) Arylsulphatase A
Description : Pancreatic lipose is an enzyme which hydrolyzes facts. It acts as a/an (A) peptidase (B) hydrolase (C) carbohydrates (D) dehydrogenase
Description : Activity of ceruloplasmin shown in vitro: (A) Reductase (B) Hydrolase (C) Ligase (D) Oxidase
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 : In abetalipoproteinemia, the biochemical defect is in (A) Apo-B synthesis (B) Lipprotein lipase activity (C) Cholesterol ester hydrolase (D) LCAT activity
Description : Give an example of a hydrolase.
Last Answer : Acetyl choline esterase.
Description : In biotin-containing enzymes, the biotin is bound to the enzyme by (A) An amide linkage to carboxyl group of glutamine (B) A covalent bond with CO2 (C) An amide linkage to an amino group of lysine (D) An amide linkage to α-carboxyl group of protein
Description : Maple syrup urine disease results from absence or serve deficiency of (A) Homogentisate oxidase (B) Phenylalanine hydroxylase (C) Branched chain amino acid transaminase (D) None of these
Description : Lack of Glucocorticoids and mineral corticoids might be consequence of which of the following defects in the adrenal cortex? (A) Androstenadione deficiency (B) Estrone deficiency (C) 17 α-OH progesterone deficiency (D) C- α-Hydroxylase deficiency
Description : Tyrosine hydroxylase is inhibited by (A) Catecholamines (B) α−Methyldopa (C) Phenylalanine (D) Vanillyl mandelic acid
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 : In adrenogenital syndrome due to total absence of 21-hydroxylase in adrenal cortex, there is (A) Deficient secretion of glucocorticoids (B) Deficient secretion of mineralcorticoids (C) Excessive secretion of androgens (D) All of these
Description : The biosynthesis of both Catecholamine and serotonin require (A) Tyrosine hydroxylase (B) N-methyl transferase (C) Aromatic amino acid decarboxylase (D) Tryptophan pyrrolase
Description : In the synthetic pathway of epinephrine, disulfiram (antabuse) inhibits the enzyme: (A) Tyrosine hydroxylase (B) Dopamine β-hydroxylase (C) DOPA decarboxylase (D) N-methyl transferase
Description : For Catecholamine biosynthesis the rate limiting enzyme is (A) DOPA decarboxylase (B) DOPAMINE β-hydroxylase (C) Tyrosine hydroxylase (D) Phenylalanine hydroxylase
Description : The defect in adrenal cortex responsible for lack of glucocorticoids and mineralcorticoids is (A) Androstenedione deficiency (B) 17 α -OH progesterone deficiency (C) C-21 hydroxylase deficiency (D) Testosterone deficiency HORMONE METABOLISM 209