Deck 3: Pharmacodynamics: How Drugs Act

Question 1

Ionotropic receptors consist of _____ subunits.

A)three
B)four
C)five
D)six

Answer 1

C

Question 2

The anxiolytic (anxiety-reducing)effect of benzodiazepines such as diazepam occurs through _____ receptor.

A)antagonist action at the serotonin
B)agonist action at the serotonin
C)antagonist action at the GABA
D)agonist action at the GABA

Answer 2

D

Question 3

The binding of drugs to receptors involves _____ bonds that are ______.

A)weak; irreversible
B)ionic; irreversible
C)ionic; reversible
D)covalent; reversible

Answer 3

C

Question 4

The _______ can lead to a change in the functional properties of a neuron.

A)neurotransmitter alone
B)receptor alone
C)binding of neurotransmitter to receptor
D)neurotransmitter alone or the receptor alone

Question 5

Pharmacodynamics can be described as:

A)what the body does to a drug.
B)how cells bind to drugs.
C)where drugs bind to cells in the body.
D)what a drug does to the body.

Question 6

A _____ usually binds to only one _____.

A)receptor; neurotransmitter
B)neurotransmitter; receptor
C)ligand; neurotransmitter
D)neurotransmitter; ligand

Question 7

The _____ of a drug refers to how strongly it attaches to the receptor.

A)fit
B)affinity
C)binding
D)ionic nature

Question 8

Benzodiazepines are _____ agonists that _____ the conductance of chloride ions into the neuron.

A)allosteric; inhibit
B)allosteric; increase
C)inverse; facilitate
D)inverse; enhance

Question 9

The naturally occurring compounds that bind to receptors are termed:

A)neurotransmitters.
B)drugs.
C)pharmaceuticals.
D)second messengers.

Question 10

Receptors that consist of an attachment site and a pore that allows specific ions to enter the cell are referred to as _____ receptors.

A)metabotropic
B)trophic
C)G-protein-coupled
D)ionotropic

Question 11

The benzodiazepines such as diazepam bind at _____ site on the receptor as the endogenous neurotransmitter _____ of the neurotransmitter.

A)the same; and mimic the action
B)the same; and block the action
C)a different; to facilitate the action
D)a different; to inhibit the action

Question 12

Barbiturates,like benzodiazepines,_____ the effect of GABA on the _____ channel within the GABA receptor.

A)decrease; potassium
B)decrease; chloride
C)increase; sodium
D)increase; chloride

Question 13

All ionotropic receptors _____ ions.

A)are activated by
B)are deactivated by
C)allow the passage of
D)bind to

Question 14

G-protein-coupled receptors are:

A)fast.
B)ionotropic.
C)metabotropic.
D)none of the above.

Question 15

The study of how a drug interacts with a receptor is:

A)pharmacology.
B)pharmacokinetics.
C)pharmacodynamics.
D)molecular physiology.

Question 16

Receptors that open and close a channel or pore are known as _____ receptors.

A)metabotropic
B)trophic
C)G-protein-coupled
D)ionotropic

Question 17

Ionotropic receptors consist of _____ coils embedded in the membrane with their attachment sites _____ the membrane.

A)spring; outside
B)spring; inside and outside
C)helical; outside
D)helical; beside

Question 18

G-protein-coupled receptors:

A)are sometimes referred to as ionotropic receptors.
B)possess a pore that opens,which allows ions to enter the cell.
C)typically are made up of five helical,membrane-spanning coils.
D)involve the release of an attached intracellular protein after a drug binds.

Question 19

The study of what the body does to a drug is _______,and the study of what the drug does to the body is _______.

A)anatomy; physiology
B)physiology; anatomy
C)pharmacokinetics; pharmacodynamics
D)pharmacodynamics; pharmacokinetics

Question 20

A _____ can usually bind to many _____.

A)receptor; neurotransmitters
B)neurotransmitter; receptor subtypes
C)ligand; neurotransmitters
D)neurotransmitter; ligands

Question 21

G-protein-coupled receptors are considered to be _____,while ionotropic are _____ receptors.

A)slow; fast
B)fast; direct
C)direct; fast
D)indirect; slow

Question 22

All of the following are types of receptors EXCEPT:

A)carrier proteins.
B)enzymes.
C)ion channel receptors.
D)cyclic AMP.

Question 23

Transport proteins are thought to exist in all of the following ionic states EXCEPT:

A)open to cytoplasm of the presynaptic cell.
B)open to the synapse.
C)open to the calcium channels of the presynaptic neuron.
D)blocked,but with the transmitter "trapped" inside.

Question 24

Upon activation of a metabotropic receptor,which of the following changes membrane permeability by opening and closing ion channels?

A)adenylate cyclase
B)G protein
C)cAMP
D)neurotransmitter

Question 25

The first messenger would be the _____,and the second messenger would be the _____.

A)cAMP; neurotransmitter
B)neurotransmitter; cAMP
C)neurotransmitter; G protein
D)G protein; cAMP

Question 26

The primary advantage of G-protein-coupled receptors over ionotropic receptors is that they:

A)amplify cellular signal.
B)work more rapidly.
C)enhance cellular metabolism.
D)inhibit the formation of second messengers.

Question 27

In metabotropic receptors:

A)G proteins activate the extracellular recognition site.
B)the associated ion channel activates the G protein.
C)the associated ion channel activates the receptor recognition site.
D)the activated extracellular receptor in turn activates the G protein.

Question 28

Membrane-spanning receptor proteins include:

A)G-protein-coupled receptors,but not carrier or transport proteins.
B)carrier or transport proteins,but not G-protein-coupled receptors.
C)both G-protein-coupled receptors and carrier or transport proteins.
D)neither G-protein-coupled receptors nor carrier or transport proteins.

Question 29

Presynaptic transporters would ______ the level of neurotransmitter in the ______.

A)decrease; presynaptic terminal
B)decrease; synaptic cleft
C)increase; presynaptic terminal
D)increase; synaptic cleft

Question 30

Drugs that block the action of presynaptic carrier proteins are expected to ______ the level of neurotransmitter in the synapse,whereas drugs that facilitate the action of presynaptic carrier proteins are expected to _____ the level of neurotransmitter in the synapse _____.

A)decrease; decrease
B)increase; increase
C)increase; decrease
D)decrease; increase

Question 31

Based on the concept of homeostatic control,you might expect drugs that block the action of carrier proteins to _____ the number of postsynaptic receptors for the endogenous neurotransmitter; further,you might expect drugs that facilitate the action of carrier proteins to _____ the number of postsynaptic receptors for the endogenous neurotransmitter.

A)decrease; decrease
B)increase; increase
C)increase; decrease
D)decrease; increase

Question 32

All of the following are considered primary intracellular pathways for modulation of synaptic transmission EXCEPT:

A)cyclic guanosine monophosphate (cGMP).
B)inositol triphosphate (IP3).
C)diacylglycerol (DG).
D)cyclic adenosine monophosphate (cAMP).

Question 33

The __________ is referred to as the "second messenger."

A)G protein
B)neurotransmitter
C)cAMP
D)receptor

Question 34

G-protein-coupled receptors consist of a _______ protein chain arranged as _______ transmembrane alpha helices.

A)single; 5
B)double; 5
C)single; 7
D)double; 7

Question 35

All of the following are second messengers EXCEPT:

A)G protein
B)calcium ions
C)cAMP
D)nitric oxide

Question 36

After a metabotropic receptor is activated,the _____ directly activates specific genes,and the _____ directly opens or closes ion channels.

A)G protein; adenylate cyclase
B)adenylate cyclase; G protein
C)cAMP; cAMP
D)cAMP; adenylate cyclase

Question 37

The _____ activates the G protein,and the _____ activates adenylate cyclase.

A)receptor; G protein
B)receptor; cAMP
C)cAMP; receptor
D)neurotransmitter; G protein

Question 38

The _____ activates the receptor and the _____ activates cAMP.

A)G protein; neurotransmitter
B)G protein; adenylate cyclase
C)neurotransmitter; adenylate cyclase
D)neurotransmitter; G protein

Question 39

All of the following are second messengers EXCEPT:

A)neurotransmitters
B)calcium ions
C)carbon monoxide
D)nitric oxide

Question 40

G-protein-coupled receptors respond to binding of a neurotransmitter by altering:

A)the external domain of the ion channel.
B)enzymes in the postsynaptic cell.
C)DNA replication.
D)chloride influx into the cell.

Question 41

Exposure to a drug that inhibits the breakdown of a neurotransmitter (NT)increases the level of NT by inhibiting breakdown:

A)in the synapse; an example of such a drug is acetylcholine esterase.
B)mainly in the presynaptic terminal; an example of such a drug is monoamine oxidase.
C)in the synapse; an example of such a drug is an acetylcholine esterase inhibitor.
D)in the presynaptic terminal; an example of such a drug is an acetylcholine esterase inhibitor.

Question 42

New advances in pharmacology enable,for the first time,the development of drugs that bind to:

A)more than one receptor.
B)one receptor only.
C)more than one neurotransmitter.
D)one neurotransmitter only.

Question 43

Janette has been prescribed an antidepressant; over time,she may have to increase her dose due to receptor:

A)upregulation.
B)supersensitivity.
C)desensitization.
D)over production.

Question 44

Side effects of a drug include those related to:

A)the primary mechanism of the drug such as blocking 5-HT receptors.
B)the secondary mechanism of the drug such as blocking cholinergic receptors.
C)both primary and secondary mechanisms of the drug.
D)neither of these mechanisms-side effects are unrelated to drug action.

Question 45

Bill has been taking Prozac (fluoxetine),a selective serotonin reuptake inhibitor,for his depression.But the drug has become less effective over time.This effect may be due to receptor:

A)upregulation.
B)sensitization.
C)adaptation.
D)desensitization.

Question 46

A racemic mixture contains:

A)50 percent active drugs and 50 percent inactive drugs.
B)25 percent active drugs and 75 percent inactive drugs.
C)75 percent active drugs and 25 percent inactive drugs.
D)100 percent active drugs

Question 47

The two main factors that determine potency are:

A)number of synapses and receptors.
B)number of receptors and strength of binding.
C)number of neurotransmitters and synapses.
D)number of drug molecules and strength of binding.

Question 48

The downregulation of receptors means that receptors:

A)decrease in size.
B)decrease in number.
C)increase in number.
D)move to another location along the membrane.

Question 49

When a drug is taken for a long period of time,receptors become _____ due to the receptors' _____.

A)desensitized; deregulation
B)sensitized; deregulation
C)desensitized.upregulation
D)sensitized.upregulation.

Question 50

Within the context of the dose-response curve,the _____ of the curve describes the association between the dose of the drug and its overall effect.

A)variability
B)height
C)slope
D)potency

Question 51

Acetylcholine esterase and monoamine oxidase are examples of:

A)G-protein-coupled receptors.
B)carrier/transport proteins.
C)directly gated ion channels.
D)enzyme receptor proteins.

Question 52

Isomers represent forms of a molecule that are:

A)identical in all respects.
B)identical save for a handful of different atoms.
C)charged versus uncharged.
D)mirror images of one another.

Question 53

Potency refers to the:

A)absolute number of molecules of drug required to elicit a response.
B)maximum effect obtainable.
C)individual differences in drug response.
D)relative safety of the drug.

Question 54

Molecular isomers of drugs are _____ similar but are not _____active.

A)chemically; biologically
B)chemically; behaviorally
C)biologically; chemically
D)biologically; behaviorally

Question 55

A new nerve gas,Agousin,has been developed that acts on the cholinergic system.Agousin would likely work as a(n)_____ inhibitor.

A)reversible acetylcholine esterase
B)reversible monoamine oxidase
C)irreversible monoamine oxidase
D)irreversible acetylcholine esterase

Question 56

The amount of drug that must be given to produce a given effect is called the drug:

A)efficacy.
B)potency.
C)intensity.
D)affinity.

Question 57

Some drugs are more selective than the endogenous:

A)receptors.
B)ligands.
C)neurotransmitters.
D)antagonists.

Question 58

Acetylcholine esterase is found in the _____ and monoamine oxidase is found in the _____.

A)synaptic cleft; synaptic cleft
B)synaptic cleft; presynaptic terminal
C)presynaptic terminal; presynaptic terminal
D)presynaptic terminal; synaptic cleft

Question 59

The upregulation of receptors means that receptors:

A)increase in size
B)increase in activity
C)increase in number
D)move to another location along the membrane

Question 60

The location of the dose-response curve along the horizontal axis reflects:

A)the therapeutic index of a drug.
B)the efficacy of a drug.
C)individual differences in drug response.
D)the potency of a drug.

Question 61

If simultaneous administration of an agonist and antagonist cause a downward shift in the maximal effect of an agonist's response,the antagonist would be considered:

A)allosteric.
B)competitive.
C)noncompetitive.
D)reversible.

Question 62

A drug that exerts an effect similar to and occupies the same receptor site as the naturally occurring compound is a(n):

A)mimicker.
B)antagonist.
C)agonist.
D)facilitator.

Question 63

The duration of the ligand-receptor interaction is its:

A)maximal effect.
B)potency.
C)residence time.
D)the therapeutic index.

Question 64

The peak of the dose-response curve indicates:

A)the therapeutic index of a drug.
B)the efficacy of a drug.
C)individual differences in drug response.
D)the potency of a drug.

Question 65

The practice of combining medications to improve therapeutic outcome is:

A)pharmacodynamic redundancy.
B)pharmacokinetic dosing.
C)polypharmacy.
D)clinical dosing.

Question 66

A drug that binds to a receptor site that elicits an opposite effect to that observed when an endogenous neurotransmitter binds is referred to as a(n):

A)partial antagonist.
B)allosteric agonist.
C)competitive antagonist.
D)inverse agonist.

Question 67

The therapeutic index refers to the:

A)absolute number of molecules of drug required to elicit a response.
B)maximum effect obtainable.
C)individual differences in drug response.
D)relative safety of the drug.

Question 68

A drug that is more potent than another drug has a:

A)larger maximal effect.
B)larger ED₅₀.
C)larger LD₅₀.
D)smaller ED₅₀.

Question 69

The variability and slope of the dose-response curve refer to:

A)the number of molecules of drug required to elicit a response.
B)the maximum effect obtainable with the drug.
C)whether the drug acts on presynaptic or postsynaptic receptors.
D)individual differences in response to the drug.

Question 70

A fast dissociation rate refers to:

A)maximal effect.
B)potency.
C)residence time.
D)the therapeutic index.

Question 71

If simultaneous administration of an agonist and antagonist cause a rightward shift in the maximal effect of an agonist's response,the antagonist would be considered:

A)allosteric.
B)competitive.
C)noncompetitive.
D)reversible.

Question 72

The therapeutic index is defined as the ratio of:

A)efficacy to potency.
B)potency to efficacy.
C)ED₅₀ to LD₅₀.
D)LD₅₀ to ED₅₀.

Question 73

In the context of a dose-response curve,the relationship between a drug dosage and the effect observed is referred to as its:

A)efficacy.
B)slope.
C)potency.
D)variability.

Question 74

_____ is when two drugs have the same or overlapping mechanism of action.

A)Pharmacodynamic redundancy
B)Pharmacokinetic dosing
C)Polypharmacy
D)Clinical dosing

Question 75

A drug that is more efficacious than another drug has a:

A)larger maximum effect.
B)larger ED₅₀.
C)larger TI.
D)smaller LD₅₀.

Question 76

The binding site for the endogenous ligand on a receptor is the _____ site.

A)allosteric
B)orthosteric
C)associate
D)facilitator

Question 77

A drug that blocks the effect of,and occupies the same receptor site as,the naturally occurring compound is termed a(n):

A)mimicker.
B)antagonist.
C)agonist.
D)facilitator.

Question 78

The fact that caffeine cannot exert as much central nervous system stimulation as amphetamine indicates that caffeine:

A)is less potent than amphetamine.
B)is less efficacious than amphetamine.
C)has a lower therapeutic index than amphetamine.
D)has a steeper slope than amphetamine on a dose-response curve.

Question 79

In a given population,the dose-response curve for the dose of drug that produces the desired effect may overlap with the dose response curve for the lethal dose of the drug.For this reason,a more useful index of the margin of safety for a drug is the ratio of the:

A)LD₅₀ to ED₅₀.
B)ED₅₀ to LD₅₀.
C)ED₉₉ to LD₁.
D)LD₁ to ED₉₉.

Question 80

The dose of drug that produces the effect desired in half of the subjects is called the drug's:

A)half-life.
B)therapeutic index.
C)ED₅₀.
D)LD₅₀.