901.Which of the following drugs has a high bioavailability
A.Acyclovir
B.Cyclosporine
C.Metoprolol
D.Diazepam
E.Verapamil

902.Which of the following is not an inhibitor of hepatic drug-metabolising enzymes
A.Metronidazole
B.Cimetidine
C.Isoniazid
D.Allopurinol
E.Rifampicin

903.The most important factor limiting drug permeations is
A.Aqueous diffusion
B.Lipid diffusion
C.Special carriers
D.Endocytosis
E.Exocytosis

904.Lipid diffusion is most dependent on
A.area
B.permeability coefficient
C.concentration gradient
D.thickness of the membrane
E.lipid:aqueouspartition coefficient

905.Excretion of salicylic acid pKa=3.0 will be increased by
A.acidifying the urine
B.alkalinising the urine
C.increasing the unprotonised form
D.decreasing the ionized form
E.none of the above

906.Receptors determine
A.concentration of drug required
B.limit maximal effect of a drug
C.selectivity of drug action
D.mediate actions of antagonists
E.all of the above

907.The best characterized drug receptors are
A.regulatory proteins
B.enzymes
C.transport proteins
D.structural proteins
E.none of the above

908.The receptor affinity for binding a drug is high if
A.Emaxis high
B.Emaxis low
C.KD is low
D.KD is high
E.EC50 is high

909.Spare receptors
A.Are different from non-spare receptors
B.Not present in heart muscle
C.Increase the EC50
D.Increase the sensitivity to a drug
E.Increase the KD

910.The effects of a non-competitive antagonist
A.Can be overcome by increasing agonist concentration
B.Reduce Emax
C.Reduce EC50
D.Emaxremains the same
E.None of the above