EXAM 1: NEUROBIOLOGY &
PHARMACOKINETICS/PHARMACODYNAMICS
Questions 1–200
SECTION 1: BASIC NEUROBIOLOGY (Questions 1–30)
QUESTION 1
Which part of the neuron is primarily responsible for receiving signals from other
neurons?
A) Axon
B) Dendrites
C) Myelin sheath
D) Soma
ANSWER: B
RATIONALE: Dendrites receive incoming electrical and chemical signals from other
neurons and transmit them toward the cell body. The axon transmits signals away from
the cell body .
QUESTION 2
An action potential is initiated when:
A) Potassium channels open
B) Sodium channels open
C) Calcium channels open
D) Chloride channels open
,ANSWER: B
RATIONALE: Voltage-gated sodium channels open, allowing sodium influx and
depolarization of the neuron, which initiates the action potential. Potassium channels
then open for repolarization .
QUESTION 3
Which neurotransmitter is the primary inhibitory neurotransmitter in the central nervous
system?
A) Glutamate
B) Dopamine
C) GABA (gamma-aminobutyric acid)
D) Norepinephrine
ANSWER: C
RATIONALE: GABA is the main inhibitory neurotransmitter in the CNS. It hyperpolarizes
postsynaptic membranes, reducing neuronal firing. Glutamate is the primary excitatory
neurotransmitter .
QUESTION 4
Which neurotransmitter is the primary excitatory neurotransmitter in the brain?
A) GABA
B) Glycine
C) Glutamate
D) Dopamine
ANSWER: C
RATIONALE: Glutamate activates NMDA, AMPA, and kainate receptors, mediating fast
excitatory synaptic transmission, learning, and memory.
,QUESTION 5
The monoamine hypothesis of depression proposes that depression is caused by a
deficiency in which neurotransmitters?
A) GABA and glutamate
B) Serotonin and norepinephrine
C) Acetylcholine and histamine
D) Dopamine and glycine
ANSWER: B
RATIONALE: The monoamine hypothesis suggests that decreased availability of
serotonin, norepinephrine, and/or dopamine in the synaptic cleft contributes to
depressive symptoms. This is the basis for most antidepressant mechanisms .
QUESTION 6
Which receptor type produces rapid, short-lived effects by directly opening ion
channels?
A) G-protein coupled receptors (metabotropic)
B) Ionotropic receptors
C) Tyrosine kinase receptors
D) Nuclear receptors
ANSWER: B
RATIONALE: Ionotropic receptors (e.g., GABA-A, NMDA, AMPA, nicotinic ACh) are
ligand-gated ion channels that open directly upon neurotransmitter binding, producing
fast synaptic transmission (milliseconds) .
, QUESTION 7
Which receptor type produces slower but longer-lasting effects via second messenger
systems?
A) Ionotropic receptors
B) Metabotropic receptors (G-protein coupled)
C) Voltage-gated channels
D) Gap junctions
ANSWER: B
RATIONALE: Metabotropic receptors are G-protein coupled receptors (GPCRs) that
activate intracellular second messenger cascades (cAMP, IP3, DAG), resulting in slower
but more prolonged and diverse effects .
QUESTION 8
Which enzyme is responsible for breaking down monoamine neurotransmitters within
the presynaptic neuron?
A) Acetylcholinesterase
B) Monoamine oxidase (MAO)
C) Catechol-O-methyltransferase (COMT)
D) Cytochrome P450
ANSWER: B
RATIONALE: Monoamine oxidase (MAO) is the enzyme responsible for breaking down
monoamine neurotransmitters (serotonin, norepinephrine, dopamine) within the
presynaptic neuron. MAO inhibitors (MAOIs) block this enzyme .
PHARMACOKINETICS/PHARMACODYNAMICS
Questions 1–200
SECTION 1: BASIC NEUROBIOLOGY (Questions 1–30)
QUESTION 1
Which part of the neuron is primarily responsible for receiving signals from other
neurons?
A) Axon
B) Dendrites
C) Myelin sheath
D) Soma
ANSWER: B
RATIONALE: Dendrites receive incoming electrical and chemical signals from other
neurons and transmit them toward the cell body. The axon transmits signals away from
the cell body .
QUESTION 2
An action potential is initiated when:
A) Potassium channels open
B) Sodium channels open
C) Calcium channels open
D) Chloride channels open
,ANSWER: B
RATIONALE: Voltage-gated sodium channels open, allowing sodium influx and
depolarization of the neuron, which initiates the action potential. Potassium channels
then open for repolarization .
QUESTION 3
Which neurotransmitter is the primary inhibitory neurotransmitter in the central nervous
system?
A) Glutamate
B) Dopamine
C) GABA (gamma-aminobutyric acid)
D) Norepinephrine
ANSWER: C
RATIONALE: GABA is the main inhibitory neurotransmitter in the CNS. It hyperpolarizes
postsynaptic membranes, reducing neuronal firing. Glutamate is the primary excitatory
neurotransmitter .
QUESTION 4
Which neurotransmitter is the primary excitatory neurotransmitter in the brain?
A) GABA
B) Glycine
C) Glutamate
D) Dopamine
ANSWER: C
RATIONALE: Glutamate activates NMDA, AMPA, and kainate receptors, mediating fast
excitatory synaptic transmission, learning, and memory.
,QUESTION 5
The monoamine hypothesis of depression proposes that depression is caused by a
deficiency in which neurotransmitters?
A) GABA and glutamate
B) Serotonin and norepinephrine
C) Acetylcholine and histamine
D) Dopamine and glycine
ANSWER: B
RATIONALE: The monoamine hypothesis suggests that decreased availability of
serotonin, norepinephrine, and/or dopamine in the synaptic cleft contributes to
depressive symptoms. This is the basis for most antidepressant mechanisms .
QUESTION 6
Which receptor type produces rapid, short-lived effects by directly opening ion
channels?
A) G-protein coupled receptors (metabotropic)
B) Ionotropic receptors
C) Tyrosine kinase receptors
D) Nuclear receptors
ANSWER: B
RATIONALE: Ionotropic receptors (e.g., GABA-A, NMDA, AMPA, nicotinic ACh) are
ligand-gated ion channels that open directly upon neurotransmitter binding, producing
fast synaptic transmission (milliseconds) .
, QUESTION 7
Which receptor type produces slower but longer-lasting effects via second messenger
systems?
A) Ionotropic receptors
B) Metabotropic receptors (G-protein coupled)
C) Voltage-gated channels
D) Gap junctions
ANSWER: B
RATIONALE: Metabotropic receptors are G-protein coupled receptors (GPCRs) that
activate intracellular second messenger cascades (cAMP, IP3, DAG), resulting in slower
but more prolonged and diverse effects .
QUESTION 8
Which enzyme is responsible for breaking down monoamine neurotransmitters within
the presynaptic neuron?
A) Acetylcholinesterase
B) Monoamine oxidase (MAO)
C) Catechol-O-methyltransferase (COMT)
D) Cytochrome P450
ANSWER: B
RATIONALE: Monoamine oxidase (MAO) is the enzyme responsible for breaking down
monoamine neurotransmitters (serotonin, norepinephrine, dopamine) within the
presynaptic neuron. MAO inhibitors (MAOIs) block this enzyme .
