NUR 751 Pharmacology Basics and Cell
Physiology–Questions and Answers | 2026 Update |
100% Correct.
Receptor Theory
-Concept where ligand binding activates or deactivates receptors
- effect is produced by ligand binding
-effect is absent when not bound by ligand
Agonist
Binds to and activates a receptor
Antagonist
Binds to a receptor without activating it
Competitive antagonism
Increasing antagonist concentration inhibits agonist response
Noncompetitive antagonism
-Antagonist prevents receptor activation despite high agonist concentration
-covalent bonding
-allosteric inhibition
Partial agonists/agonist-antagonists
-Activate receptors less completely than full agonists
-can reduce agonist effects
,Allosteric inhibition
Inhibition of receptor function by binding at a site other than the active site
Hypersensitive
Exhibiting an exaggerated/inappropriate response to drug in sensitized individual
Hyporeactive
Exhibiting a diminished response to stimuli
Tolerance
Decreased response to a drug following repeated exposure
Tachyphylaxis
Rapid development of tolerance to a drug
Additive effect
Combined effect of two drugs equals the sum of their individual effects
Synergistic effect
Combined effect of two drugs is greater than the sum of their individual effects
Distribution
Movement of drugs within the body
Hepatic Clearance
R = Q(Cin-Cout)
Where:
, R = rate of clearance
Q = Liver blood flow
Cin = Concentration flowing into the liver
Cout = Concentration flowing out of the liver
If the liver could completely extract the drug from afferent flow, clearance would equal liver
blood flow.
Volume of Distribution
-Theoretical volume drugs would occupy in the body
-highly lipid soluble drugs have large calculated Vd
Enantiomers
Mirror image molecules with different pharmacokinetic and pharmacodynamic properties
Pharmacodynamic variability
Variability in drug response due to differences in enzyme activity and genetics
Pharmacokinetic Variability
Bioavailability
Renal function
Hepatic function
Cardiac function
Patient age
Extracellular Fluid
Physiology–Questions and Answers | 2026 Update |
100% Correct.
Receptor Theory
-Concept where ligand binding activates or deactivates receptors
- effect is produced by ligand binding
-effect is absent when not bound by ligand
Agonist
Binds to and activates a receptor
Antagonist
Binds to a receptor without activating it
Competitive antagonism
Increasing antagonist concentration inhibits agonist response
Noncompetitive antagonism
-Antagonist prevents receptor activation despite high agonist concentration
-covalent bonding
-allosteric inhibition
Partial agonists/agonist-antagonists
-Activate receptors less completely than full agonists
-can reduce agonist effects
,Allosteric inhibition
Inhibition of receptor function by binding at a site other than the active site
Hypersensitive
Exhibiting an exaggerated/inappropriate response to drug in sensitized individual
Hyporeactive
Exhibiting a diminished response to stimuli
Tolerance
Decreased response to a drug following repeated exposure
Tachyphylaxis
Rapid development of tolerance to a drug
Additive effect
Combined effect of two drugs equals the sum of their individual effects
Synergistic effect
Combined effect of two drugs is greater than the sum of their individual effects
Distribution
Movement of drugs within the body
Hepatic Clearance
R = Q(Cin-Cout)
Where:
, R = rate of clearance
Q = Liver blood flow
Cin = Concentration flowing into the liver
Cout = Concentration flowing out of the liver
If the liver could completely extract the drug from afferent flow, clearance would equal liver
blood flow.
Volume of Distribution
-Theoretical volume drugs would occupy in the body
-highly lipid soluble drugs have large calculated Vd
Enantiomers
Mirror image molecules with different pharmacokinetic and pharmacodynamic properties
Pharmacodynamic variability
Variability in drug response due to differences in enzyme activity and genetics
Pharmacokinetic Variability
Bioavailability
Renal function
Hepatic function
Cardiac function
Patient age
Extracellular Fluid
