MSN 671 TEST BANK BUNDLE 2026
TESTED QUESTIONS AND FULL
SOLUTION GRADED A+
◉ Voltage-sensitive ion channels. Answer: Activated by changes in
membrane voltage or charge.
◉ Ionotropic receptors. Answer: Another name for ligand-gated ion
channels.
◉ Clinical relevance of ligand-gated vs voltage-sensitive channels.
Answer: LGICs → rapid effects (e.g., benzodiazepines, ketamine);
VSSCs/VSCCs → anticonvulsants, mood stabilizers, analgesics.
◉ Dual role of ligand-gated ion channels. Answer: They act as both
receptors and ion channels.
◉ Structure of LGICs. Answer: Several subunits arranged around an ion
channel with binding sites for NTs, drugs, ions, and allosteric
modulators.
◉ Pentameric receptors. Answer: Receptors with 5 subunits.
◉ Tetrameric receptors. Answer: Receptors with 4 subunits + re-entrant
loop.
, ◉ Examples of pentameric receptors. Answer: GABAA_AA, Nicotinic
acetylcholine receptor (nAChR), 5-HT3, Glycine receptor.
◉ Examples of tetrameric receptors. Answer: AMPA, NMDA, Kainate
(glutamate receptors).
◉ Pentameric LGIC subtypes. Answer: GABAA_AA, nAChR, 5-HT3,
Glycine receptors.
◉ Tetrameric LGIC subtypes. Answer: AMPA, Kainate, NMDA.
◉ Assembly of pentameric receptors. Answer: 5 subunits form a
functional ion channel; subunit composition defines receptor subtype.
◉ Assembly of tetrameric receptors. Answer: 4 subunits form a
functional ion channel with re-entrant loops; subunit composition can
determine drug binding.
◉ Allosteric modulation. Answer: Binding of a ligand at a site different
from the NT site to alter receptor/channel activity.
◉ Positive allosteric modulator (PAM). Answer: Enhances the effect of
the neurotransmitter. Example: Benzodiazepines at GABAA_AA.
◉ Negative allosteric modulator (NAM). Answer: Reduces or blocks the
effect of the neurotransmitter. Example: Ketamine or PCP at NMDA.
TESTED QUESTIONS AND FULL
SOLUTION GRADED A+
◉ Voltage-sensitive ion channels. Answer: Activated by changes in
membrane voltage or charge.
◉ Ionotropic receptors. Answer: Another name for ligand-gated ion
channels.
◉ Clinical relevance of ligand-gated vs voltage-sensitive channels.
Answer: LGICs → rapid effects (e.g., benzodiazepines, ketamine);
VSSCs/VSCCs → anticonvulsants, mood stabilizers, analgesics.
◉ Dual role of ligand-gated ion channels. Answer: They act as both
receptors and ion channels.
◉ Structure of LGICs. Answer: Several subunits arranged around an ion
channel with binding sites for NTs, drugs, ions, and allosteric
modulators.
◉ Pentameric receptors. Answer: Receptors with 5 subunits.
◉ Tetrameric receptors. Answer: Receptors with 4 subunits + re-entrant
loop.
, ◉ Examples of pentameric receptors. Answer: GABAA_AA, Nicotinic
acetylcholine receptor (nAChR), 5-HT3, Glycine receptor.
◉ Examples of tetrameric receptors. Answer: AMPA, NMDA, Kainate
(glutamate receptors).
◉ Pentameric LGIC subtypes. Answer: GABAA_AA, nAChR, 5-HT3,
Glycine receptors.
◉ Tetrameric LGIC subtypes. Answer: AMPA, Kainate, NMDA.
◉ Assembly of pentameric receptors. Answer: 5 subunits form a
functional ion channel; subunit composition defines receptor subtype.
◉ Assembly of tetrameric receptors. Answer: 4 subunits form a
functional ion channel with re-entrant loops; subunit composition can
determine drug binding.
◉ Allosteric modulation. Answer: Binding of a ligand at a site different
from the NT site to alter receptor/channel activity.
◉ Positive allosteric modulator (PAM). Answer: Enhances the effect of
the neurotransmitter. Example: Benzodiazepines at GABAA_AA.
◉ Negative allosteric modulator (NAM). Answer: Reduces or blocks the
effect of the neurotransmitter. Example: Ketamine or PCP at NMDA.
