Description : Immediate precursor of epinephrine is (A) Metanephrine (B) Norepinephrine (C) Dopa (D) Dopamine
Last Answer : Answer : B
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 : Tyrosine hydroxylase is inhibited by (A) Catecholamines (B) α−Methyldopa (C) Phenylalanine (D) Vanillyl mandelic acid
Last Answer : Answer : A
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 : An enzyme involved in catabolism of catecholamines is (A) Dopa decarboxylase (B) Aromatic amino acid decarboxylase (C) Monoamine oxidase (D) Catechol oxidas
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 : Blood brain barrier can be crossed by (A) Epinephrine (B) Dopamine (C) Dopa (D) All of these
Description : Following events occur in the cytoplasm and not inside storage vesicles, except (a) Conversion of tyrosine to dopa (b) Conversion of dopa to dopamine (c) Conversion of dopamine to norepinephrine (d) Conversion of dopamine to 3,4 dihydroxy phenyl acetic acid
Last Answer : Ans: C
Description : The following enzymes on the left are responsible for the synthesis of the neurotransmitters on the right: a. monoamine oxidase: noradrenaline b. cholinesterase: acetylcholine c. catechol-o-methyl transferase: dopamine d. dopa decarboxylase: adrenaline
Last Answer : dopa decarboxylase: adrenaline
Description : Methyldopa lowers BP by: A. Inhibiting dopa decarboxylase in adrenergic nerve endings B. Generating α-methyl noradrenaline in brain which reduces sympathetic tone C. Generating α-methyl ... as a false transmitter in peripheral adrenergic nerve endings D. Activating vascular dopamine receptors
Last Answer : B. Generating α-methyl noradrenaline in brain which reduces sympathetic tone
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 : All the following hormones promote hyperglycemia except (A) Epinephrine (B) Norepinephrine (C) Insulin (D) Glucagon
Description : Dopamine is synthesised from (A) Dihydroxyphenylalanine (B) Epinephrine (C) Norepinephrine (D) Metanephrine
Description : Tyrosine is required for the synthesis of all of the following except (A) Melatonin (B) Epinephrine (C) Norepinephrine (D) Thyroxine 222 MCQs IN BIOCHEMISTRY
Description : Cyclic GMP acts as the second messenger for (A) Nerve growth factor (B) Atrial natriuretic factor (C) Epinephrine (D) Norepinephrine
Description : Epinephrine is derived from norepinephrine by (A) Decarboxylation (B) Hydroxylation (C) Oxidation (D) N-methylation
Last Answer : Answer : D
Description : Epinephrine is rapidly metabolized by (A) Monoamine oxidase (B) Deaminase (C) Transminase (D) Decarboxylase
Description : What is the function of epinephrine and norepinephrine? -Biology
Last Answer : answer:
Description : Choose the correct statement from the following about a1 – adrenergic receptor agonists (a) Norepinephrine > isoproterenol > epinephrine (b) Norepinephrine < epinephrine > isoproterenol (c) Epinephrine = norepinephrine >> isoproterenol (d) Epinephrine > isoproterenol > norepinephrine
Description : Select the correct statement from the following about a1 – adrenergic receptor agonists (a) Isoproterenol > epinephrine = norepinephrine (b) Epinephrine > isoproterenol > norepinephrine (c) Isoproterenol = epinephrine = norepinephrine (d) Epinephrine = norepinephrine > isoproterenol
Last Answer : Ans: A
Description : Action of norepinephrine and epinephrine are terminated by (a) Reuptake into nerve terminal (b) Dilution by diffusion and uptake at extraneuronal site (c) Metabolic transformation (d) All of the above
Last Answer : Ans: D
Description : Which of the following drugs is the drug of choice in anaphylaxis associated with bronchospasm and hypotension ? (a) Cortisone (b) Epinephrine (c) Isoproterenol (d) Norepinephrine (e) Phenylephrine
Last Answer : Ans: B
Description : The neurotransmitter agent that is normally released in the sinoatrial node of the heart in response to a blood pressure increase is (a) Acetylcholine (b) Dopamine (c) Epinephrine (d) Glutamate (e) Norepinephrine
Description : A person entering an empty room suddenly finds a snake right in front on opening the door. Which one of the following is likely to happen in his neuro- hormonal control system? ... brain. (d) Sympathetic nervous system is activated releasing epinephrine and norepinephrine from adrenal cortex.
Last Answer : (a) Sympathetic nervous system is activated releasing epinephrine and norepinephrine from adrenal medulla.
Description : Fight-or-flight reactions cause activation of (a) the parathyroid glands, leading to increased metabolic rate (b) the kidney, leading to suppression of renin- angiotensin-aldosterone pathway (c) ... epinephrine and norepinephrine (d) the pancreas leading to a reduction in the blood sugar levels.
Last Answer : (c) the adrenal medulla, leading to increased secretion of epinephrine and norepinephrine
Description : Which one of the following does not act as a neurotransmitter? (a) Cortisone (b) Acetylcholine (c) Epinephrine (d) Norepinephrine
Last Answer : (a) Cortisone
Description : Which pair of hormones has opposite, antagonistic effects? A) insulin--glucagon B) insulin--progesterone C) estrogen--thyroxin D) thyroxin--parathyroid hormone E) epinephrine--norepinephrine
Last Answer : A) insulin--glucagon
Description : What is the cascade of events that follows a stress or trauma to produce adrenal reaction? A) hypothalamus (ACTH-releasing hormone)-anterior pituitary (ACTH)-adrenal cortex mineralocorticoids and ... ) E) adrenal cortex (hormones)-hypothalamus (ACTH-releasing hormone)-anterior pituitary (ACTH)
Last Answer : A) hypothalamus (ACTH-releasing hormone)-anterior pituitary (ACTH)-adrenal cortex mineralocorticoids and glucocorticoids (regulate metabolism and sugar level)
Description : Formation of melanin from tyrosine requires the action of (A) Dopa decarboxylation (B) Diamine oxidase (C) Peroxidase (D) Tyrosinase
Description : Methyl dopa decreases blood pressure by (A) Inhibiting the synthesis of catecholamines (B) Antagonising the action of aldosterone (C) Stimulating the release of renin (D) Inhibiting the breakdown of angiotensin
Description : DOPA is an intermediate in the synthesis of (A) Thyroid hormones (B) Catecholamines (C) Melanin (D) Catecholamines and melanin
Description : Phenylalanine is the precursor of (A) L-DOPA (B) Histamine (C) Tyrosine (D) Throxine
Last Answer : C
Description : Prolactin release inhibiting hormone is believed to be (A) Serotonin (B) Norepinephrine (C) Dopanine (D) Acetyl choline
Description : Norepinephrine binds mainly to (A) α-Adrenergic receptors (B) β-Adrenergic receptrors (C) Muscarinic receptors (D) Nicotinic receptors
Description : The enzyme dopamine β-oxidase which catalyses conversion of dopamine to norepinephrine requires (A) Vitamin A (B) Vitamin C (C) Vitamin E (D) Vitamin B12
Description : Increased urinary excretion of orotic acid can occur in deficiency of (A) Orotate phosphoribosyl transferase (B) OMP decarboxylase (C) Mitochondrial ornithine transcarbamoylase (D) Any of the above
Description : Enzymic deficiency in β-aminoisobutyric aciduria is (A) Adenosine deaminase (B) Xanthine oxidase (C) Orotidylate decarboxylase (D) Transaminase
Description : Orotic aciduria type II reflects the deficiency of the enzyme: (A) Orotate phosphoribosyl transferase (B) Orotidylate decarboxylase (C) Dihydroorotase (D) Dihydroorotate dehydrogenase
Description : Orotic aciduria type I reflects the deficiency of enzymes: (A) Orotate phosphoribosyl transferase and orotidylate decarboxylase (B) Dihydroorotate dehydrogenase (C) Dihydroorotase (D) Carbamoyl phosphate synthetase
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 : Conversion of deoxyuridine monophosphate to thymidine monophosphate is catalysed by the enzyme: (A) Ribonucleotide reductase (B) Thymidylate synthetase (C) CTP synthetase (D) Orotidylic acid decarboxylase
Description : Histamine is formed from histidine by the enzyme histidine decarboxylase in the presence of (A) NAD (B) FMN (C) HS-CoA (D) B6-PO4
Description : The enzyme catalyzing conversion of androstenedione to testosterone is a (A) Oxygenase (B) Dehydrogenase (C) Isomerase (D) Decarboxylase
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 : The enzyme involved in variegate porphyria is (A) Protoporphyrinogen oxidase (B) Coproporphyrinogen oxidase (C) Uroporphyrinogen decarboxylase (D) ALA decarboxylase
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
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 : Tryptophan pyrolase is currently known as (A) Tryptophan deaminase (B) Tryptophan dioxygenase (C) Tryptophan mono oxygenase (D) Tryptophan decarboxylase
Description : The decarboxylation reaction in HMP shunt is catalysed by (A) Gluconolactone hydrolase (B) 6-Phosphogluconate dehydrogenase (C) 6-Phosphogluconate decarboxylase (D) Transaldolase