Wilkes NSG 552 Psychopharmacology Exam 1 2026 – Wilkes University
1. Which neurotransmitter is considered the primary excitatory
neurotransmitter in the central nervous system?
A. GABA
B. Glycine
C. Serotonin
D. Glutamate
Answer: D
Rationale: Glutamate is the major excitatory neurotransmitter, while GABA is the major
inhibitory neurotransmitter in the brain.
2. Which of the following describes a ‘partial agonist’?
A. It blocks the receptor completely.
B. It produces the maximal response possible.
C. It increases the activity of the receptor more than a full agonist.
D. It elicits a response that is less than the maximal response of a full agonist.
Answer: D
Rationale: Partial agonists bind to receptors but only produce a partial physiological
response compared to a full agonist.
3. The conversion of Tyrosine to L-DOPA is mediated by which enzyme?
A. DOPA decarboxylase
B. Tyrosine hydroxylase
C. MAO
D. COMT
Answer: B
,Rationale: Tyrosine hydroxylase is the rate-limiting enzyme in the synthesis of
catecholamines, converting Tyrosine to L-DOPA.
4. Which dopamine pathway is associated with the development of
extrapyramidal symptoms (EPS)?
A. Nigrostriatal
B. Mesocortical
C. Mesolimbic
D. Tuberoinfundibular
Answer: A
Rationale: The nigrostriatal pathway controls motor function; its blockade by
antipsychotics leads to EPS.
5. What occurs when a drug acts as an ‘inverse agonist’ at a receptor?
A. It mimics the natural ligand.
B. It produces the opposite effect of an agonist.
C. It blocks the agonist but has no effect on its own.
D. It irreversibly binds to the receptor.
Answer: B
Rationale: Inverse agonists bind to the same receptor as agonists but induce a
pharmacological response opposite to that of the agonist.
6. Steady state concentration of a drug is typically reached after how many half-
lives?
A. 4 to 5
B. 1 to 2
C. 10 to 12
D. 20
Answer: A
, Rationale: It generally takes 4 to 5 half-lives for a drug to reach a steady state where the
rate of administration equals the rate of elimination.
7. The Cytochrome P450 (CYP) enzyme system is primarily located in which
organ?
A. Liver
B. Kidneys
C. Brain
D. Heart
Answer: A
Rationale: The liver is the primary site for the metabolism of most psychotropic
medications via the CYP450 system.
8. Which serotonin receptor is unique because it is an ion channel rather than a
G-protein coupled receptor?
A. 5-HT1A
B. 5-HT2A
C. 5-HT7
D. 5-HT3
Answer: D
Rationale: The 5-HT3 receptor is a ligand-gated ion channel, whereas other serotonin
receptors are G-protein coupled.
9. Blockade of dopamine in the tuberoinfundibular pathway leads to an increase
in which hormone?
A. Cortisol
B. Prolactin
C. Thyroxine
D. Oxytocin
Answer: B
1. Which neurotransmitter is considered the primary excitatory
neurotransmitter in the central nervous system?
A. GABA
B. Glycine
C. Serotonin
D. Glutamate
Answer: D
Rationale: Glutamate is the major excitatory neurotransmitter, while GABA is the major
inhibitory neurotransmitter in the brain.
2. Which of the following describes a ‘partial agonist’?
A. It blocks the receptor completely.
B. It produces the maximal response possible.
C. It increases the activity of the receptor more than a full agonist.
D. It elicits a response that is less than the maximal response of a full agonist.
Answer: D
Rationale: Partial agonists bind to receptors but only produce a partial physiological
response compared to a full agonist.
3. The conversion of Tyrosine to L-DOPA is mediated by which enzyme?
A. DOPA decarboxylase
B. Tyrosine hydroxylase
C. MAO
D. COMT
Answer: B
,Rationale: Tyrosine hydroxylase is the rate-limiting enzyme in the synthesis of
catecholamines, converting Tyrosine to L-DOPA.
4. Which dopamine pathway is associated with the development of
extrapyramidal symptoms (EPS)?
A. Nigrostriatal
B. Mesocortical
C. Mesolimbic
D. Tuberoinfundibular
Answer: A
Rationale: The nigrostriatal pathway controls motor function; its blockade by
antipsychotics leads to EPS.
5. What occurs when a drug acts as an ‘inverse agonist’ at a receptor?
A. It mimics the natural ligand.
B. It produces the opposite effect of an agonist.
C. It blocks the agonist but has no effect on its own.
D. It irreversibly binds to the receptor.
Answer: B
Rationale: Inverse agonists bind to the same receptor as agonists but induce a
pharmacological response opposite to that of the agonist.
6. Steady state concentration of a drug is typically reached after how many half-
lives?
A. 4 to 5
B. 1 to 2
C. 10 to 12
D. 20
Answer: A
, Rationale: It generally takes 4 to 5 half-lives for a drug to reach a steady state where the
rate of administration equals the rate of elimination.
7. The Cytochrome P450 (CYP) enzyme system is primarily located in which
organ?
A. Liver
B. Kidneys
C. Brain
D. Heart
Answer: A
Rationale: The liver is the primary site for the metabolism of most psychotropic
medications via the CYP450 system.
8. Which serotonin receptor is unique because it is an ion channel rather than a
G-protein coupled receptor?
A. 5-HT1A
B. 5-HT2A
C. 5-HT7
D. 5-HT3
Answer: D
Rationale: The 5-HT3 receptor is a ligand-gated ion channel, whereas other serotonin
receptors are G-protein coupled.
9. Blockade of dopamine in the tuberoinfundibular pathway leads to an increase
in which hormone?
A. Cortisol
B. Prolactin
C. Thyroxine
D. Oxytocin
Answer: B
