The following inhibitor binds only to the ani-onic site of the cholinesterase enzyme: A. Neostigmine B. Physostigmine C. Edrophonium D. Dyflos

The following inhibitor binds only to the ani-onic site of
the cholinesterase enzyme:
A. Neostigmine
B. Physostigmine
C. Edrophonium
D. Dyflos
by

1 Answer

Answer :

C. Edrophonium
by

Related questions

The following inhibitor binds only to the ani-onic site of the cholinesterase enzyme: A. Neostigmine B. Physostigmine C. Edrophonium D. Dyflos

Description : The following inhibitor binds only to the ani-onic site of the cholinesterase enzyme: A. Neostigmine B. Physostigmine C. Edrophonium D. Dyflos

Last Answer : C. Edrophonium

Reactivation of cholinesterase enzyme occurs on hydrolysis of the inhibitor by the same enzyme molecule in case of the following anticholinesterase: A. Edrophonium B. Neostigmine C. Dyflos D. Tacrine

Description : Reactivation of cholinesterase enzyme occurs on hydrolysis of the inhibitor by the same enzyme molecule in case of the following anticholinesterase: A. Edrophonium B. Neostigmine C. Dyflos D. Tacrine

Last Answer : B. Neostigmine

Reactivation of cholinesterase enzyme occurs on hydrolysis of the inhibitor by the same enzyme molecule in case of the following anticholinesterase: A. Edrophonium B. Neostigmine C. Dyflos D. Tacrine

Description : Reactivation of cholinesterase enzyme occurs on hydrolysis of the inhibitor by the same enzyme molecule in case of the following anticholinesterase: A. Edrophonium B. Neostigmine C. Dyflos D. Tacrine

Last Answer : B. Neostigmine

Pseudocholinesterase differs from true cholinesterase in that: A. It does not hydrolyse acetylcholine B. It hydrolyses acetylcholine at a slower rate C. It is more susceptible to inhibition by physostigmine D. It is the only form of circulating cholinesterase

Description : Pseudocholinesterase differs from true cholinesterase in that: A. It does not hydrolyse acetylcholine B. It hydrolyses acetylcholine at a slower rate C. It is more susceptible to inhibition by physostigmine D. It is the only form of circulating cholinesterase

Last Answer : B. It hydrolyses acetylcholine at a slower rate

Pseudocholinesterase differs from true cholinesterase in that: A. It does not hydrolyse acetylcholine B. It hydrolyses acetylcholine at a slower rate C. It is more susceptible to inhibition by physostigmine D. It is the only form of circulating cholinesterase

Description : Pseudocholinesterase differs from true cholinesterase in that: A. It does not hydrolyse acetylcholine B. It hydrolyses acetylcholine at a slower rate C. It is more susceptible to inhibition by physostigmine D. It is the only form of circulating cholinesterase

Last Answer : B. It hydrolyses acetylcholine at a slower rate

Edrophonium is more suitable for differentiating myasthenic crisis from cholinergic crisis because of its: A. Shorter duration of action B. Longer duration of action C. Direct action on muscle end-plate D. Selective inhibition of true cholinesterase

Description : Edrophonium is more suitable for differentiating myasthenic crisis from cholinergic crisis because of its: A. Shorter duration of action B. Longer duration of action C. Direct action on muscle end-plate D. Selective inhibition of true cholinesterase

Last Answer : A. Shorter duration of action

Neostigmine is preferred over physostigmine for treating myasthenia gravis because: A. It is better absorbed orally B. It has longer duration of action C. It has additional direct agonistic action on nicotinic receptors at the muscle end plate D. It penetrates blood-brain barrier

Description : Neostigmine is preferred over physostigmine for treating myasthenia gravis because: A. It is better absorbed orally B. It has longer duration of action C. It has additional direct agonistic action on nicotinic receptors at the muscle end plate D. It penetrates blood-brain barrier

Last Answer : C. It has additional direct agonistic action on nicotinic receptors at the muscle end plate

Neostigmine is beneficial in cobra envenomation because: A. It binds to and inactivates cobra toxin B. It reverses coma due to cobra toxin C. It counteracts the cardio-depressant action of cobra toxin D. It antagonizes the paralysing action of cobra toxin

Description : Neostigmine is beneficial in cobra envenomation because: A. It binds to and inactivates cobra toxin B. It reverses coma due to cobra toxin C. It counteracts the cardio-depressant action of cobra toxin D. It antagonizes the paralysing action of cobra toxin

Last Answer : D. It antagonizes the paralysing action of cobra toxin

Neostigmine is beneficial in cobra envenomation because: A. It binds to and inactivates cobra toxin B. It reverses coma due to cobra toxin C. It counteracts the cardio-depressant action of cobra toxin D. It antagonizes the paralysing action of cobra toxin

Description : Neostigmine is beneficial in cobra envenomation because: A. It binds to and inactivates cobra toxin B. It reverses coma due to cobra toxin C. It counteracts the cardio-depressant action of cobra toxin D. It antagonizes the paralysing action of cobra toxin

Last Answer : D. It antagonizes the paralysing action of cobra toxin

The anticholinesterase action of edrophonium is short lasting because termination of its action depends on: A. Dissociation and diffusion of the drug from the enzyme B. Hydrolysis of the drug by the enzyme C. Synthesis of fresh enzyme molecules D. A combination of the above three processes

Description : The anticholinesterase action of edrophonium is short lasting because termination of its action depends on: A. Dissociation and diffusion of the drug from the enzyme B. Hydrolysis of the drug by the enzyme C. Synthesis of fresh enzyme molecules D. A combination of the above three processes

Last Answer : A. Dissociation and diffusion of the drug from the enzyme

Physostigmine is a competitive inhibitor of (A) Xanthine oxidase (B) Cholinesterase (C) Carbonic anhydrase (D) Monoamine oxidase

Description : Physostigmine is a competitive inhibitor of (A) Xanthine oxidase (B) Cholinesterase (C) Carbonic anhydrase (D) Monoamine oxidase

Last Answer : Answer : B

Pyridostigmine differs from neostigmine in that: A. It is more potent orally B. It is longer acting C. It produces less muscarinic side effects D. It does not have any direct action on NM receptors

Description : Pyridostigmine differs from neostigmine in that: A. It is more potent orally B. It is longer acting C. It produces less muscarinic side effects D. It does not have any direct action on NM receptors

Last Answer : B. It is longer acting

The mechanism by which neostigmine improves contraction of myasthenic muscle involves: A. Repetitive binding of the acetylcholine molecules to the same receptors at the muscle endplate B. Diffusion of acetylcholine released from motor nerve endings to a wider area activating neighbouring receptors C. Activation of motor end-plate receptors by neostigmine molecules themselves D. All of the above

Description : The mechanism by which neostigmine improves contraction of myasthenic muscle involves: A. Repetitive binding of the acetylcholine molecules to the same receptors at the muscle endplate B. Diffusion of ... Activation of motor end-plate receptors by neostigmine molecules themselves D. All of the above

Last Answer : D. All of the above

Select the option which is not correct with respect to enzyme action. (a) Substrate binds with enzyme at its active site. (b) Addition of lot of succinate does not reverse the inhibition of succinic dehydrogenase by malonate. (c) A non-competitive inhibitor binds the enzyme at a site distinct from that which binds the substrate. (d) Malonate is a competitive inhibitor of succinic dehydrogenase.

Description : Select the option which is not correct with respect to enzyme action. (a) Substrate binds with enzyme at its active site. (b) Addition of lot of succinate does not reverse the inhibition ... from that which binds the substrate. (d) Malonate is a competitive inhibitor of succinic dehydrogenase.

Last Answer : (b) Addition of lot of succinate does not reverse the inhibition of succinic dehydrogenase by malonate.

The following is a competitive type of enzyme inhibitor: A. Acetazolamide B. Disulfiram C. Physostigmine D. Theophylline

Description : The following is a competitive type of enzyme inhibitor: A. Acetazolamide B. Disulfiram C. Physostigmine D. Theophylline

Last Answer : C. Physostigmine

The following is a competitive type of enzyme inhibitor: A. Acetazolamide B. Disulfiram C. Physostigmine D. Theophylline

Description : The following is a competitive type of enzyme inhibitor: A. Acetazolamide B. Disulfiram C. Physostigmine D. Theophylline

Last Answer : C. Physostigmine

Edrophonium is more suitable for differentiating myasthenic crisis from cholinergic crisis because of its: A. Shorter duration of action B. Longer duration of action C. Direct action on muscle end-plate D. Selective inhibition of true cholinesterase

Description : Edrophonium is more suitable for differentiating myasthenic crisis from cholinergic crisis because of its: A. Shorter duration of action B. Longer duration of action C. Direct action on muscle end-plate D. Selective inhibition of true cholinesterase

Last Answer : A. Shorter duration of action

The most efficacious inhibitor of catecholamine synthesis in the body is: A. α-methyl-p-tyrosine B. α-methyldopa C. α-methyl-norepinephrine D. Entacapone

Description : The most efficacious inhibitor of catecholamine synthesis in the body is: A. α-methyl-p-tyrosine B. α-methyldopa C. α-methyl-norepinephrine D. Entacapone

Last Answer : A. α-methyl-p-tyrosine

The most effective antidote for belladonna poisoning is (a) Neostigmine (b) Physostigmine (c) Pilocarpine (d) Methacholine

Description : The most effective antidote for belladonna poisoning is (a) Neostigmine (b) Physostigmine (c) Pilocarpine (d) Methacholine

Last Answer : Ans: B

Which of the following agents is a prodrug that is much less toxic in mammals than in insects ? (a) Acetylcholine (b) Bethanechol (c) Physostigmine (d) Pilocarpine (e) Neostigmine

Description : Which of the following agents is a prodrug that is much less toxic in mammals than in insects ? (a) Acetylcholine (b) Bethanechol (c) Physostigmine (d) Pilocarpine (e) Neostigmine

Last Answer : Ans: C

A direct-acting cholinomimetic that is lipid-soluble and often used in the treatment of glaucoma is (a) Acetylcholine (b) Bethanechol (c) Physostigmine (d) Pilocarpine (e) Neostigmine

Description : A direct-acting cholinomimetic that is lipid-soluble and often used in the treatment of glaucoma is (a) Acetylcholine (b) Bethanechol (c) Physostigmine (d) Pilocarpine (e) Neostigmine

Last Answer : Ans: D

The most effective antidote for belladonna poisoning is: A. Neostigmine B. Physostigmine C. Pilocarpine D. Methacholine

Description : The most effective antidote for belladonna poisoning is: A. Neostigmine B. Physostigmine C. Pilocarpine D. Methacholine

Last Answer : B. Physostigmine

The most effective antidote for belladonna poisoning is: A. Neostigmine B. Physostigmine C. Pilocarpine D. Methacholine

Description : The most effective antidote for belladonna poisoning is: A. Neostigmine B. Physostigmine C. Pilocarpine D. Methacholine

Last Answer : B. Physostigmine

Neostigmine is preferred over physostigmine for treating myasthenia gravis because: A. It is better absorbed orally B. It has longer duration of action C. It has additional direct agonistic action on nicotinic receptors at the muscle end plate D. It penetrates blood-brain barrier

Description : Neostigmine is preferred over physostigmine for treating myasthenia gravis because: A. It is better absorbed orally B. It has longer duration of action C. It has additional direct agonistic action on nicotinic receptors at the muscle end plate D. It penetrates blood-brain barrier

Last Answer : C. It has additional direct agonistic action on nicotinic receptors at the muscle end plate

What happens to an enzyme when a competitive inhibitor binds to it?

Description : What happens to an enzyme when a competitive inhibitor binds to it?

Last Answer : Need answer

In competitive inhibition, the inhibitor (A) Competes with the enzyme (B) Irreversibly binds with the enzyme (C) Binds with the substrate (D) Competes with the substrate

Description : In competitive inhibition, the inhibitor (A) Competes with the enzyme (B) Irreversibly binds with the enzyme (C) Binds with the substrate (D) Competes with the substrate

Last Answer : Answer : D

Sildenafil is contraindicated in patients taking the following class of drugs: A. α-adrenergic blockers B. β-adrenergic blockers C. Organic nitrates D. Angiotensin converting enzyme inhibitors

Description : Sildenafil is contraindicated in patients taking the following class of drugs: A. α-adrenergic blockers B. β-adrenergic blockers C. Organic nitrates D. Angiotensin converting enzyme inhibitors

Last Answer : C. Organic nitrates

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

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

Sildenafil is contraindicated in patients taking the following class of drugs: A. α-adrenergic blockers B. β-adrenergic blockers C. Organic nitrates D. Angiotensin converting enzyme inhibitors

Description : Sildenafil is contraindicated in patients taking the following class of drugs: A. α-adrenergic blockers B. β-adrenergic blockers C. Organic nitrates D. Angiotensin converting enzyme inhibitors

Last Answer : C. Organic nitrates

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

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

The major postjunctional cholinergic receptor is of the muscarinic type at the following site: A. Postganglionic parasympathetic B. Adrenal medulla C. Autonomic ganglia D. Neuromuscular junction

Description : The major postjunctional cholinergic receptor is of the muscarinic type at the following site: A. Postganglionic parasympathetic B. Adrenal medulla C. Autonomic ganglia D. Neuromuscular junction

Last Answer : A. Postganglionic parasympathetic

The major postjunctional cholinergic receptor is of the muscarinic type at the following site: A. Postganglionic parasympathetic B. Adrenal medulla C. Autonomic ganglia D. Neuromuscular junction

Description : The major postjunctional cholinergic receptor is of the muscarinic type at the following site: A. Postganglionic parasympathetic B. Adrenal medulla C. Autonomic ganglia D. Neuromuscular junction

Last Answer : A. Postganglionic parasympathetic

The organophosphates produce irreversible inhibition of cholinesterase because: A. They bind to an allosteric site of the enzyme resulting in unfavourable conformation of esteratic site to bind acetylcholine B. Regeneration time of the phosphorylated enzyme is longer than the turnover time of the enzyme molecules C. Phosphorylation results in rapid degradation of enzyme molecules D. They are neither metabolized nor excreted from the body

Description : The organophosphates produce irreversible inhibition of cholinesterase because: A. They bind to an allosteric site of the enzyme resulting in unfavourable conformation of esteratic site to bind ... degradation of enzyme molecules D. They are neither metabolized nor excreted from the body

Last Answer : B. Regeneration time of the phosphorylated enzyme is longer than the turnover time of the enzyme molecules

The organophosphates produce irreversible inhibition of cholinesterase because: A. They bind to an allosteric site of the enzyme resulting in unfavourable conformation of esteratic site to bind acetylcholine B. Regeneration time of the phosphorylated enzyme is longer than the turnover time of the enzyme molecules C. Phosphorylation results in rapid degradation of enzyme molecules D. They are neither metabolized nor excreted from the body

Description : The organophosphates produce irreversible inhibition of cholinesterase because: A. They bind to an allosteric site of the enzyme resulting in unfavourable conformation of esteratic site to bind ... degradation of enzyme molecules D. They are neither metabolized nor excreted from the body

Last Answer : B. Regeneration time of the phosphorylated enzyme is longer than the turnover time of the enzyme molecules

Tyramine induces release of noradrenaline from adrenergic nerve endings: A. By depolarizing the axonal membrane B. By mobilizing Ca2+ C. By a nonexocytotic process D. Only in the presence of MAO inhibitors

Description : Tyramine induces release of noradrenaline from adrenergic nerve endings: A. By depolarizing the axonal membrane B. By mobilizing Ca2+ C. By a nonexocytotic process D. Only in the presence of MAO inhibitors

Last Answer : C. By a nonexocytotic process

Muscarinic cholinergic receptors: A. Are located only on parasympathetically innervated effector cells B. Mediate responses by opening an intrinsic Na+ ion channel C. Are present on vascular endothelium which has no cholinergic nerve supply D. Predominate in the autonomic ganglia

Description : Muscarinic cholinergic receptors: A. Are located only on parasympathetically innervated effector cells B. Mediate responses by opening an intrinsic Na+ ion channel C. Are present on vascular endothelium which has no cholinergic nerve supply D. Predominate in the autonomic ganglia

Last Answer : C. Are present on vascular endothelium which has no cholinergic nerve supply

Which of the following organs is innervated only by parasympathetic nerves: A. Iris muscles B. Ciliary muscle C. Sweat glands D. Splenic capsule

Description : Which of the following organs is innervated only by parasympathetic nerves: A. Iris muscles B. Ciliary musclele C. Sweat glands D. Splenic capsu

Last Answer : B. Ciliary musclele

Which of the following organs is innervated only by parasympathetic nerves: A. Iris muscles B. Ciliary muscle C. Sweat glands D. Splenic capsule

Description : Which of the following organs is innervated only by parasympathetic nerves: A. Iris muscles B. Ciliary muscle C. Sweat glands D. Splenic capsule

Last Answer : B. Ciliary muscle

The anticholinesterase action of edrophonium is short lasting because termination of its action depends on: A. Dissociation and diffusion of the drug from the enzyme B. Hydrolysis of the drug by the enzyme C. Synthesis of fresh enzyme molecules D. A combination of the above three processes

Description : The anticholinesterase action of edrophonium is short lasting because termination of its action depends on: A. Dissociation and diffusion of the drug from the enzyme B. Hydrolysis of the drug by the enzyme C. Synthesis of fresh enzyme molecules D. A combination of the above three processes

Last Answer : A. Dissociation and diffusion of the drug from the enzyme

In hyperthyroidism, β adrenergic blockers are used: A. To induce euthyroid state B. As definitive therapy C. For rapid control of certain symptoms while awaiting response to carbimazole D. To reduce basal metabolic rate

Description : Select the β-adrenergic blocker that has additional α1 blocking, vasodilator and antioxidant properties: A. Carvedilol B. Celiprolol C. Acebutolol D. Metoprolol

Last Answer : C. Acebutolol

Select the β-adrenergic blocker that has additional α1 blocking, vasodilator and antioxidant properties: A. Carvedilol B. Celiprolol C. Acebutolol D. Metoprolol

Description : Select the β-adrenergic blocker that has additional α1 blocking, vasodilator and antioxidant properties: A. Carvedilol B. Celiprolol C. Acebutolol D. Metoprolol

Last Answer : A. Carvedilol

In a patient of myocardial infarction, β adrenergic blockers are used with the following aim/aims: A. To reduce the incidence of reinfarction B. To prevent cardiac arrhythmias C. To limit size of the infarct D. All of the above

Description : In a patient of myocardial infarction, β adrenergic blockers are used with the following aim/aims: A. To reduce the incidence of reinfarction B. To prevent cardiac arrhythmias C. To limit size of the infarct D. All of the above

Last Answer : D. All of the above

Select the β adrenergic blocker that is primarily eliminated unchanged by renal excretion: A. Propranolol B. Metoprolol C. Esmolol D. Atenolol

Description : Select the β adrenergic blocker that is primarily eliminated unchanged by renal excretion: A. Propranolol B. Metoprolol C. Esmolol D. Atenolol

Last Answer : D. Atenolol

The following is not a feature of cardioselective beta blockers, when compared to propranolol: A. They are ineffective in suppressing muscle tremor B. They are safer in diabetics C. They are less likely to cause bradycardia D. They are less likely to worsen Raynaud’s disease

Description : The following is not a feature of cardioselective beta blockers, when compared to propranolol: A. They are ineffective in suppressing muscle tremor B. They are safer in diabetics C. They are less likely to cause bradycardia D. They are less likely to worsen Raynaud’s disease

Last Answer : C. They are less likely to cause bradycardia

Esmolol has the following features except: A. Rapidly developing, shortlasting β adrenergic blockade B. Cardioselectivity of action C. Intrinsic sympathomimetic activity D. Suitability for intraoperative use

Description : Esmolol has the following features except: A. Rapidly developing, shortlasting β adrenergic blockade B. Cardioselectivity of action C. Intrinsic sympathomimetic activity D. Suitability for intraoperative use

Last Answer : C. Intrinsic sympathomimetic activity

Select the ultrashort acting cardioselective β adrenergic blocker: A. Bisoprolol B. Timolol C. Sotalol D. Esmolol

Description : Select the ultrashort acting cardioselective β adrenergic blocker: A. Bisoprolol B. Timolol C. Sotalol D. Esmolol

Last Answer : D. Esmolol

β-adrenergic blockers are indicated in the following conditions except: A. Hypertrophic cardiomyopathy B. Congestive heart failure C. Vasospastic angina pectoris D. Dissecting aortic aneurysm

Description : β-adrenergic blockers are indicated in the following conditions except: A. Hypertrophic cardiomyopathy B. Congestive heart failure C. Vasospastic angina pectoris D. Dissecting aortic aneurysm

Last Answer : C. Vasospastic angina pectoris

The following disease is worsened by propranolol: A. Glaucoma B. Raynaud’s disease C. Benign prostatic hypertrophy D. Parkinsonism

Description : The following disease is worsened by propranolol: A. Glaucoma B. Raynaud’s disease C. Benign prostatic hypertrophy D. Parkinsonism

Last Answer : B. Raynaud’s disease

Select the drug which can impair carbohydrate tolerance in prediabetics but prolongs insulin hypoglycaemia: A. Salbutamol B. Propranolol C. Prazosin D. Nifedipine

Description : Select the drug which can impair carbohydrate tolerance in prediabetics but prolongs insulin hypoglycaemia: A. Salbutamol B. Propranolol C. Prazosin D. Nifedipine

Last Answer : B. Propranolol

The β adrenergic blocker having β1 selectivity, intrinsic sympathomimetic activity and membrane stabilizing property is: A. Carvedilol B. Atenolol C. Acebutolol D. Metoprolol

Description : The β adrenergic blocker having β1 selectivity, intrinsic sympathomimetic activity and membrane stabilizing property is: A. Carvedilol B. Atenolol C. Acebutolol D. Metoprolol

Last Answer : C. Acebutolol