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 : Precursor of Vitamin A is (A) α-Carotene (B) β-Carotene (C) γ-Carotene (D) All of these VITAMINS 121
Last Answer : Answer : D
Description : Conversion of β-carotene into retinal requires the presence of (A) β-Carotene dioxygenase (B) Bile salts (C) Molecular oxygen (D) All of these
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
Last Answer : Answer : B
Description : Tryptophan pyrolase is currently known as (A) Tryptophan deaminase (B) Tryptophan dioxygenase (C) Tryptophan mono oxygenase (D) Tryptophan decarboxylase
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 : Microsomal hydroxylase system contains a (A) Di-oxygenase (B) Mono-oxygenase (C) Both (A) and (B) (D) None of thse
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
Last Answer : Answer : A
Description : One international Unit of vitamin A is the activity present in (A) 0.3 µg of β-Carotene (B) 0.3 µg of retinol (C) 0.6 µg of retinoic acid (D) All of these
Description : Two molecules of vitamin A can be formed from 1 molecule of (A) α-Carotene (B) β-Carotene (C) γ-Carotene (D) All of these
Description : The molecule of vitamin A1 contains (A) Benzene ring (B) β-Ionone ring (C) β-Carotene ring (D) None of these
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 : The biosynthesis of both Catecholamine and serotonin require (A) Tyrosine hydroxylase (B) N-methyl transferase (C) Aromatic amino acid decarboxylase (D) Tryptophan pyrrolase
Description : A deficiency of copper effects the formation of normal collagen by reducing the activity of which of the following enzyme? (A) Prolyl hydroxylase (B) Lysyl oxidase (C) Lysyl hydroxylase (D) Glucosyl transferase
Description : An inborn error, maple syrup urine disease is due to deficiency of the enzyme: (A) Isovaleryl-CoAhydrogenase (B) Phenylalnine hydroxylase (C) Adenosyl transferase (D) α-Ketoacid decarboxylase
Description : The β-ring of 7-dehydrocholesterol is cleaved to form cholecalciferol by (A) Infrared light (B) Dim light (C) Ultraviolet irridation with sunlight (D) Light of the tube lights
Last Answer : Answer : C
Description : For Catecholamine biosynthesis the rate limiting enzyme is (A) DOPA decarboxylase (B) DOPAMINE β-hydroxylase (C) Tyrosine hydroxylase (D) Phenylalanine hydroxylase
Description : Anti-oxidant activity is present in (A) β-Carotene (B) Retinol (C) Retinoic acid (D) All of these
Description : The organism commonly used for the production of carotene is/ are β A- Phycomycesblakesleeanus B- Phycomycesblakesleeanus C- Blakesleatrispora D- all of these
Last Answer : all of these
Description : Pseudomonas aeruginosa forms a blue water soluble pigment called A-pyocyanin B- chlororaphin C- pyoverdin D-β-carotene
Last Answer : pyocyanin
Last Answer : (A) β-Carotene
Description : Which is a pro vitamin or vitamin that has antioxidant properties? (A) Beta carotene (B) Vitamin E (C) Vitamin C (D) Vitamin D
Description : Vitamin K is involved in posttranslational modification of the blood clotting factors by acting as cofactor for the enzyme: (A) Carboxylase (B) Decarboxylase (C) Hydroxylase (D) Oxidase
Description : Zymogen is a (A) Vitamin (B) Enzyme precursor (C) Modulator (D) Hormone
Description : Cholesterol is a precursor in the biogenesis of (A) Vitamin A (B) Vitamin D (C) Vitamin E (D) None of these
Description : The precursor of bile salts, sex hormones and vitamin D is (A) Diosgenin (B) Cholesterol (C) Campesterol (D) Ergosterol
Description : Homogentisic oxidase is an (A) Oxidase (B) Monooxygenase (C) Dioxygenase (D) Anaerotic dehydrogenase
Description : All the following statement about hydroxyproline are true except (A) There is no codon for hydroxyproline (B) It is present in large amounts in collagen (C) Free proline cannot be hydroxylated to hydroxyproline (D) Hydroxylation of proline residues is catalysed by a dioxygenase
Description : The signal sequence of proteins is cleaved off (A) On the ribosomes immediately after synthesis (B) In the endoplasmic reticulum (C) During processing in Golgi apparatus (D) During passage through the cell membrane
Description : As a result of each oxidation a long chain fatty acid is cleaved to give (A) An acid with 3-carbon less and propionyl CoA (B) An acid with 2-carbon less and acetyl CoA (C) An acid with 2-carbon less and acetyl CoA (D) An acid with 4-carbon and butyryl CoA
Description : A growing peptide in a ribosome can not be shifted to the adjacent ribosome because (A) It is firmly attached (B) It will get the amino acid cleaved (C) The gap between the ribosomes is too big for a shift (D) The adjacent ribosomes have different composition
Description : IgG cleaved by papain into (A) Two light and two heavy chains (B) Two Fab and one Fc fragments (C) Two pairs of one light and one heavy chain each (D) One Fab and two Fc fragments
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 : 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 : Spinach leaves are rich source of---- A. Amino acid B. Iron (Answer) C. Vitamin E D. Carotene
Last Answer : B. Iron (Answer)
Description : Good vision depends on adequate intake of carotene rich food. Select the best option from the following statements. (1) Vitamin A derivatives are formed from carotene. (2) The photopigments are embedded in the membrane discs of the inner ... (1) and (3) (c) (2), (3) and (4) (d) (1) and (2)
Last Answer : (b) (1) and (3)
Description : Spinach leaves are rich source of (1) Vitamin A (2) Iron (3) Carotene (4) Vitamin E
Last Answer : (2) Iron
Description : Vitamin K is involved in posttranslational modification of the blood clotting factors by acting as cofactor for the enzyme (A) Carboxylase (B) Decarboxylase (C) Hydroxylase (D) Oxidase
Last Answer : (A) Carboxylase
Description : Good vision depends on adequate intake of carotene rich food : Select the best option from the following statements : (a) Vitamin A derivatives are formed from carotene (b) The photopigments are embedded in the membrane discs of the inner segment ... (a) and (c) (3) (b), (c) and (d) (4) (a) and (b)
Last Answer : (1) (a), (c) and (d)
Description : In the blood the vitamin esters are attached to (A) α1-lipoproteins (B) α2-lipoproteins (C) β-lipoproteins (D) γ-lipoproteins
Description : Vitamin K is a cofactor for (A) Gamma carboxylation of glutamic acid residue (B) β-Oxidation of fatty acid (C) Formation of γ-amino butyrate (D) Synthesis of tryptophan