NURS 6630 WEEK 8 ASSIGNMENT 1 SHORT ANSWER
ASSESSMENT 2026/2027 | Complete Solutions |
Verified Answers | Pass Guaranteed - A+ Graded
Neurobiology & Mechanisms of Action
(10 Questions)
Q1: A 34-year-old patient with major depressive disorder is started on fluoxetine. The
therapeutic effect of this medication is primarily mediated by:
A. Blocking reuptake of dopamine and norepinephrine at the presynaptic membrane
B. Inhibiting monoamine oxidase to prevent breakdown of serotonin and
norepinephrine
C. Blocking the serotonin transporter (SERT) to increase synaptic serotonin
concentration [CORRECT]
D. Antagonizing 5-HT2A receptors to indirectly enhance dopamine release in the
prefrontal cortex
Correct Answer: C
Rationale: The best answer is C. Fluoxetine is a selective serotonin reuptake inhibitor
(SSRI); it binds to the serotonin transporter on the presynaptic neuron and blocks
reuptake, allowing serotonin to remain in the synaptic cleft longer and enhance
postsynaptic signaling. Option A describes bupropion's mechanism; option B
describes MAOIs like phenelzine; and option D describes the mechanism of atypical
antipsychotics such as aripiprazole or brexpiprazole.
,Q2: A patient with schizophrenia is prescribed aripiprazole. This medication is best
classified as a:
A. Full dopamine D2 receptor agonist
B. Dopamine D2 receptor antagonist with high affinity
C. Dopamine D2 receptor partial agonist with functional selectivity [CORRECT]
D. Dopamine D3 receptor inverse agonist
Correct Answer: C
Rationale: The best answer is C. Aripiprazole is a partial agonist at D2 receptors,
meaning it stabilizes dopaminergic tone by acting as a functional agonist in
hypoactive pathways (mesocortical) and a functional antagonist in hyperactive
pathways (mesolimbic). It is not a full agonist; it is not a pure antagonist like
haloperidol; and while it has some D3 activity, it is not classified as a D3 inverse
agonist.
Q3: Lithium's mood-stabilizing effect is thought to involve modulation of which
intracellular signaling pathway?
A. Direct agonism of GABA-A receptors
B. Inhibition of inositol monophosphatase and reduction of inositol triphosphate
(IP3) signaling [CORRECT]
C. Blockade of voltage-gated sodium channels in neuronal membranes
D. Activation of NMDA glutamate receptors
Correct Answer: B
Rationale: The best answer is B. Lithium inhibits inositol monophosphatase and
inositol polyphosphate 1-phosphatase, depleting inositol and dampening the
phosphoinositide second messenger system that is overactive in bipolar disorder. It
does not directly act on GABA-A receptors (that's benzodiazepines); sodium channel
blockade is more relevant to carbamazepine and lamotrigine; and NMDA activation
would be excitotoxic, not therapeutic.
, Q4: A patient asks how benzodiazepines like lorazepam reduce anxiety. The nurse
practitioner explains that these medications:
A. Block serotonin reuptake to enhance mood regulation
B. Enhance GABA-A receptor chloride channel opening, increasing neuronal
inhibition [CORRECT]
C. Inhibit norepinephrine reuptake to reduce sympathetic arousal
D. Antagonize glutamate NMDA receptors to decrease excitatory neurotransmission
Correct Answer: B
Rationale: The best answer is B. Benzodiazepines bind to a specific allosteric site on
the GABA-A receptor complex, increasing the frequency of chloride channel opening
and hyperpolarizing the postsynaptic neuron, which produces anxiolytic, sedative,
and muscle relaxant effects. SSRIs affect serotonin reuptake; SNRIs affect
norepinephrine; and NMDA antagonism describes ketamine or memantine, not
benzodiazepines.
Q5: The mechanism of action of bupropion in treating depression differs from SSRIs
in that bupropion:
A. Is a potent inhibitor of serotonin reuptake with minimal effects on other
monoamines
B. Primarily inhibits reuptake of norepinephrine and dopamine without significant
serotonin effects [CORRECT]
C. Blocks both serotonin and norepinephrine reuptake equally
D. Inhibits monoamine oxidase to increase all monoamine levels
Correct Answer: B
Rationale: The best answer is B. Bupropion is a norepinephrine-dopamine reuptake
inhibitor (NDRI); it has negligible affinity for the serotonin transporter, which explains
why it does not cause the sexual dysfunction or weight gain commonly seen with
SSRIs. Option A describes SSRIs; option C describes SNRIs like venlafaxine; and
option D describes MAOIs.
ASSESSMENT 2026/2027 | Complete Solutions |
Verified Answers | Pass Guaranteed - A+ Graded
Neurobiology & Mechanisms of Action
(10 Questions)
Q1: A 34-year-old patient with major depressive disorder is started on fluoxetine. The
therapeutic effect of this medication is primarily mediated by:
A. Blocking reuptake of dopamine and norepinephrine at the presynaptic membrane
B. Inhibiting monoamine oxidase to prevent breakdown of serotonin and
norepinephrine
C. Blocking the serotonin transporter (SERT) to increase synaptic serotonin
concentration [CORRECT]
D. Antagonizing 5-HT2A receptors to indirectly enhance dopamine release in the
prefrontal cortex
Correct Answer: C
Rationale: The best answer is C. Fluoxetine is a selective serotonin reuptake inhibitor
(SSRI); it binds to the serotonin transporter on the presynaptic neuron and blocks
reuptake, allowing serotonin to remain in the synaptic cleft longer and enhance
postsynaptic signaling. Option A describes bupropion's mechanism; option B
describes MAOIs like phenelzine; and option D describes the mechanism of atypical
antipsychotics such as aripiprazole or brexpiprazole.
,Q2: A patient with schizophrenia is prescribed aripiprazole. This medication is best
classified as a:
A. Full dopamine D2 receptor agonist
B. Dopamine D2 receptor antagonist with high affinity
C. Dopamine D2 receptor partial agonist with functional selectivity [CORRECT]
D. Dopamine D3 receptor inverse agonist
Correct Answer: C
Rationale: The best answer is C. Aripiprazole is a partial agonist at D2 receptors,
meaning it stabilizes dopaminergic tone by acting as a functional agonist in
hypoactive pathways (mesocortical) and a functional antagonist in hyperactive
pathways (mesolimbic). It is not a full agonist; it is not a pure antagonist like
haloperidol; and while it has some D3 activity, it is not classified as a D3 inverse
agonist.
Q3: Lithium's mood-stabilizing effect is thought to involve modulation of which
intracellular signaling pathway?
A. Direct agonism of GABA-A receptors
B. Inhibition of inositol monophosphatase and reduction of inositol triphosphate
(IP3) signaling [CORRECT]
C. Blockade of voltage-gated sodium channels in neuronal membranes
D. Activation of NMDA glutamate receptors
Correct Answer: B
Rationale: The best answer is B. Lithium inhibits inositol monophosphatase and
inositol polyphosphate 1-phosphatase, depleting inositol and dampening the
phosphoinositide second messenger system that is overactive in bipolar disorder. It
does not directly act on GABA-A receptors (that's benzodiazepines); sodium channel
blockade is more relevant to carbamazepine and lamotrigine; and NMDA activation
would be excitotoxic, not therapeutic.
, Q4: A patient asks how benzodiazepines like lorazepam reduce anxiety. The nurse
practitioner explains that these medications:
A. Block serotonin reuptake to enhance mood regulation
B. Enhance GABA-A receptor chloride channel opening, increasing neuronal
inhibition [CORRECT]
C. Inhibit norepinephrine reuptake to reduce sympathetic arousal
D. Antagonize glutamate NMDA receptors to decrease excitatory neurotransmission
Correct Answer: B
Rationale: The best answer is B. Benzodiazepines bind to a specific allosteric site on
the GABA-A receptor complex, increasing the frequency of chloride channel opening
and hyperpolarizing the postsynaptic neuron, which produces anxiolytic, sedative,
and muscle relaxant effects. SSRIs affect serotonin reuptake; SNRIs affect
norepinephrine; and NMDA antagonism describes ketamine or memantine, not
benzodiazepines.
Q5: The mechanism of action of bupropion in treating depression differs from SSRIs
in that bupropion:
A. Is a potent inhibitor of serotonin reuptake with minimal effects on other
monoamines
B. Primarily inhibits reuptake of norepinephrine and dopamine without significant
serotonin effects [CORRECT]
C. Blocks both serotonin and norepinephrine reuptake equally
D. Inhibits monoamine oxidase to increase all monoamine levels
Correct Answer: B
Rationale: The best answer is B. Bupropion is a norepinephrine-dopamine reuptake
inhibitor (NDRI); it has negligible affinity for the serotonin transporter, which explains
why it does not cause the sexual dysfunction or weight gain commonly seen with
SSRIs. Option A describes SSRIs; option C describes SNRIs like venlafaxine; and
option D describes MAOIs.
