Description : Receptor agonists possess: A. Affinity but no intrinsic activity B. Intrinsic activity but no affinity C. Affinity and intrinsic activity with a + sign D. Affinity and intrinsic activity with a – sign
Last Answer : C. Affinity and intrinsic activity with a + sign
Description : Study of drug-receptor interaction has now shown that: A. Maximal response occurs only when all receptors are occupied by the drug B. Drugs exert an all or none' action on a ... lock and key' structural features D. Properties of affinity' and intrinsic activity' are independently variable
Last Answer : D. Properties of ‘affinity’ and ‘intrinsic activity’ are independently variable
Description : What is true in relation to drug receptors: A. All drugs act through specific receptors B. All drug receptors are located on the surface of the target cells C. Agonists induce a conformational change in the receptor D. Partial agonists have low affinity for the receptor
Last Answer : C. Agonists induce a conformational change in the receptoR
Last Answer : C. Agonists induce a conformational change in the receptor
Description : A partial agonist can antagonise the effects of a full agonist because it has: A. High affinity but low intrinsic activity B. Low affinity but high intrinsic activity C. No affinity and low intrinsic activity D. High affinity but no intrinsic activity
Last Answer : A. High affinity but low intrinsic activity
Description : Agonists affect the receptor molecule in the following manner: A. Alter its amino acid sequence B. Denature the receptor protein C. Alter its folding or alignment of subunits D. Induce covalent bond formation
Last Answer : C. Alter its folding or alignment of subunits
Description : The following is not a feature of competitive antagonists: A. Chemical resemblance with the agonist B. Parallel rightward shift of the agonist log doseresponse curve C. Suppression of maximal agonist response D. Apparent reduction in agonist affinity for the receptor
Last Answer : C. Suppression of maximal agonist response
Description : The receptor transduction mechanism with the fastest time-course of response effectuation is: A. Adenylyl cyclase-cyclic AMP pathway B. Phospholipase C-IP3: DAG pathway C. Intrinsic ion channel operation D. Protein synthesis modulation
Last Answer : C. Intrinsic ion channel operation
Description : The following receptor has an intrinsic ion channel: A. Histamine H1 receptor B. Histamine H2 receptor C. Adrenergic alfa receptor D. GABA-benzodiazepine receptor
Last Answer : D. GABA-benzodiazepine receptor
Description : The following receptor type has 7 helical membrane spanning amino acid segments with 3 extracellular and 3 intracellular loops: A. Tyrosine protein kinase receptor B. Gene expression regulating receptor C. Intrinsic ion channel containing receptor D. G protein coupled receptor
Last Answer : D. G protein coupled receptor
Description : Currently, the first choice drug for open angle glaucoma is: A. Miotic eye drops B. Ocular α2 adrenergic agonists C. Ocular prostaglandin analogues D. Ocular β adrenergic blockers
Last Answer : D. Ocular β adrenergic blockers
Description : The following statement is not true of log dose-response curve: A. It is almost linear except at the ends B. It is a rectangular hyperbola C. It facilitates comparison of different agonists D. It can help in discriminating between competitive and noncompetitive antagonists
Last Answer : B. It is a rectangular hyperbola
Description : Down regulation of receptors can occur as a consequence of: A. Continuous use of agonists B. Continuous use of antagonists C. Chronic use of CNS depressants D. Denervation
Last Answer : A. Continuous use of agonists
Description : Receptors perform the following function/functions: A. Ligand recognition B. Signal transduction C. Both ligand recognition and signal transduction D. Disposal of agonists and antagonists
Last Answer : C. Both ligand recognition and signal transduction
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
Description : Agonist induced autophosphorylation, internalization and down regulation is a distinctive feature of: A. G-protein coupled receptors B. Intrinsic ion channel containing receptors C. Tyrosine protein kinase receptors D. Receptors regulating gene expression
Last Answer : C. Tyrosine protein kinase receptors
Description : A receptor which itself has enzymatic property is: A. Insulin receptor B. Progesterone receptor C. Thyroxine receptor D. Glucagon receptor
Last Answer : A. Insulin receptor
Description : Agonistic action on which of the following adrenergic receptors located on ciliary epithelial cells reduces aqueous secretion: A. β1 receptor B. β2 receptor C. α1 receptor D. α2 receptor
Last Answer : D. α2 receptor
Description : 81. Which one of the following pairs of hormones are the examples of those that can easily pass through the cell membrane of the target cell and bind to a receptor inside it (mostly in the nucleus) (1) Cortisol, testosterone (2) Insulin, glucagon (3) Thyroxin, Insulin (4) Somatostatin, oxytocin
Last Answer : Cortisol, testosterone
Description : Cholinergic muscarinic receptor stimulation produces the following effects except: A. Sweating B. Rise in blood pressure C. Bradycardia D. Urination
Last Answer : B. Rise in blood pressure
Description : All of the following subserve as intracellular second messengers in receptor mediated signal transduction except: A. Cyclic AMP B. Inositol trisphosphate C. Diacyl glycerols D. G proteins
Last Answer : D. G proteins
Description : Select the receptor that is located intracellularly: A. Opioid μ receptor B. Steroid receptor C. Prostaglandin receptor D. Angiotensin receptor
Last Answer : B. Steroid receptor
Description : Which of the following is a G protein coupled receptor: A. Muscarinic cholinergic receptor B. Nicotinic cholinergic receptor C. Glucocorticoid receptor D. Insulin receptor
Last Answer : A. Muscarinic cholinergic receptor
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
Last Answer : Ans: C
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 : The mechanism of action of barbiturates differs from that of benzodiazepines in that they: A. Do not affect the GABA-benzodiazepine receptor-chloride channel complex B. Act as inverse agonists at the ... without affecting its life time D. Have both GABA-facilitatory as well as GABA-mimetic actions
Last Answer : D. Have both GABA-facilitatory as well as GABA-mimetic actions
Description : 3 Diffusion of drugs across cell membrane: A. Is dependent upon metabolic activity of the cell B. Is competitively inhibited by chemically related drugs C. Is affected by extent of ionization of drug molecules D. Exhibits saturation kinetics
Last Answer : C. Is affected by extent of ionization of drug molecules
Description : To be used as a topically applied ocular beta blocker a drug should have the following properties except: A. Strong local anaesthetic activity B. High lipophilicity C. High ocular capture D. Low systemic activity
Last Answer : A. Strong local anaesthetic activity
Description : Morphine has high affinity for the following opioid receptor(s). (a) µ (Mu) (b) k (Kappa) (c) d (Delta) (d) All of the above
Description : Morphine has high affinity for the following opioid receptor(s): A. μ (Mu) B. κ (Kappa) C. δ (Delta) D. All of the above
Last Answer : A. μ (Mu
Description : The GABAB receptor: A. Is an intrinsic ion channel containing receptor B. Mediates neuronal depolarization C. Is insensitive to blockade by bicuculline D. Regulates intracellular cAMP
Last Answer : C. Is insensitive to blockade by bicuculline
Last Answer : D. Disposal of agonists and antagonists
Description : All the following statements about epidermal growth factor are true except (A) It is a protein (B) It possess quaternary structure (C) Its receptor is made up of a single polypeptide chain (D) Its receptor possesses tyrosine kinase domain
Last Answer : Answer : B
Description : An addicting drug which produces little or no physical dependence is: A. Diazepam B. Phenobarbitone C. Amphetamine D. Methadone
Last Answer : C. Amphetamine
Description : A drug ‘R’ producing no response by itself causes the log dose-response curve of another drug ‘S’ to shift to the right in a parallel manner without decreasing the maximal response: Drug ‘R’ is a: A. Partial agonist B. Inverse agonist C. Competitive antagonist D. Noncompetitive antagonist
Last Answer : C. Competitive antagonist
Description : Monitoring of blood levels of diuretic drugs is not practised because: A. No sensitive methods for measuring blood levels of diuretics are available B. It is easier to measure the effect of these ... Response to diuretics is not related to their blood levels D. Diuretics need activation in the body
Last Answer : B. It is easier to measure the effect of these drugs
Description : An 'orphan drug' is: A. A very cheap drug B. A drug which has no therapeutic use C. A drug needed for treatment or prevention of a rare disease D. A drug which acts on Orphanin receptors
Last Answer : C. A drug needed for treatment or prevention of a rare disease
Description : Timolol eye drops are preferred over pilocarpine eye drops by glaucoma patients because: A. Timolol is more effective than pilocarpine B. Timolol acts by enhancing uveo-scleral outflow C. Timolol produces less ocular side effects D. There are no contraindications to timolol
Last Answer : C. Timolol produces less ocular side effects
Description : Acetylcholine has no therapeutic application because: A. None of its actions are beneficial in any condition B. Its effects are transient C. It produces wide spread actions affecting many organs D. Both ‘B’ and ‘C’ are correct
Last Answer : D. Both ‘B’ and ‘C’ are correct
Description : In congestive heart failure patients: A. Volume of distribution of all drugs is increased B. Hepatic clearance of drugs is unaffected C. Orally administered diuretics may not be effective, but the same may work parenterally D. Inotropic action of digoxin is attenuated
Last Answer : C. Orally administered diuretics may not be effective, but the same may work parenterally