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 : 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 : 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 : 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 : Which of the following is not the basis for subclassifying β adrenergic receptors into β1 and β2 : A. Selectivity of agonists B. Selectivity of antagonists C. Transducer pathway of response effectuation D. Organ selective location
Last Answer : C. Transducer pathway of response effectuation
Description : Which of the following is not the basis for subclassifying β adrenergic receptors into β 1 and β 2: A. Selectivity of agonists B. Selectivity of antagonists C. Transducer pathway of response effectuation D. Organ selective location
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 : 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 : 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 : 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 : 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 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 cardiac muscarinic receptors: A. Are of the M1 subtype B. Are of the M2 subtype C. Are selectively blocked by pirenzepine D. Function through the PIP2 → IP3/DAG pathway
Last Answer : B. Are of the M2 subtype
Description : The antagonism between adrenaline and histamine is called ‘physiological antagonism’ because: A. Both are physiologically present in the body B. They act on physiological receptors C. Both affect many physiological processes D. They have opposite physiological effects
Last Answer : D. They have opposite physiological effects
Description : The bladder trigone and prostatic muscles are relaxed by: A. Adrenergic α1 agonists B. Adrenergic α1 antagonists C. Adrenergic α2 agonists D. Adrenergic α2 antagonists
Last Answer : B. Adrenergic α1 antagonists
Description : Leukotriene antagonists are used in bronchial asthma: A. For terminating acute attacks B. As monotherapy in place of β2 agonists C. As adjuvants to β2 agonists for avoiding corticosteroids D. As nebulized powder in refractory cases
Last Answer : C. As adjuvants to β2 agonists for avoiding corticosteroids
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 : Drugs acting through receptors exhibit the following features except: A. Structural specificity B. High potency C. Competitive antagonism D. Dependence of action on lipophilicity
Last Answer : D. Dependence of action on lipophilicity
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 : 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 : 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
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
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
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 : The following statement is true in relation to drug toxicity' and poisoning': A. The two terms are synonymous B. When a toxic effect requires specific treatment, it is called poisoning C. ... is called poisoning D. Toxicity is caused by drugs while poisoning is caused by other harmful chemicals
Last Answer : C. A toxic effect which endangers life by markedly affecting vital functions is called poisoning
Description : Select the route of administration which carries the highest risk of adversely affecting vital functions: A. Intra arterial injection B. Intrathecal injection C. Intravenous injection D. Intramuscular injection
Last Answer : C. Intravenous injection
Description : The bacteria in a colony are unable to perform transduction. How would this hurt the bacterial colony's chance for survival?
Last Answer : The bacteria would generally be more similar
Description : In patients of hepatic cirrhosis: A. The extent of change in pharmacokinetics of drugs can be predicted from the values of liver function tests B. High doses of furosemide can be safely used C. Metformin is the preferred oral hypoglycaemic D. Disposition of atenolol is not significantly affected
Last Answer : D. Disposition of atenolol is not significantly affected
Description : STAT proteins are (A) Thermostat proteins of brain (B) Glucostat proteins of hepatocyte cell membrane (C) Short term activators of translation (D) Signal transduction and activators of transcription
Last Answer : Answer : D
Description : Interindividual variations in equieffective doses of a drug are most marked if it is disposed by: A. Glomerular filtration B. Tubular secretion C. Both glomerular filtration and tubular secretion D. Hepatic metabolism
Last Answer : D. Hepatic metabolism
Description : Which of the following types of drug metabolizing enzymes are inducible: A. Microsomal enzymes B. Nonmicrosomal enzymes C. Both microsomal and nonmicrosomal enzymes D. Mitochondrial enzymes
Last Answer : A. Microsomal enzymes
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 : The essential feature in drug addiction is: A. Physical dependence B. Psychological dependence C. Both physical and psychological dependence D. Psychiatric abnormality
Last Answer : B. Psychological dependence
Description : When therapeutic effects decline both below and above a narrow range of doses, a drug is said to exhibit: A. Ceiling effect B. Desensitization C. Therapeutic window phenomenon D. Nonreceptor mediated action
Last Answer : C. Therapeutic window phenomenon