Potential AI Generated Questions For N154 Midterm
2 With Complete Solutions
What is the primary function of ligand-gated neurotransmitter receptors? (From
"Ligand-gated neurotransmitter receptors" notes) - ANSWER The primary function of
ligand-gated neurotransmitter receptors is to control the flow of ions through their
receptor channels, producing excitatory or inhibitory synaptic potentials in response to
neurotransmitter binding.
Name the major excitatory and inhibitory ligand-gated receptors in the central nervous
system. (From "Ligand-gated neurotransmitter receptors" notes) - ANSWER The major
excitatory ligand-gated receptors in the central nervous system are nicotinic
acetylcholine receptors (nAChRs) and glutamate receptors (AMPA, NMDA, and
Kainate). The major inhibitory ligand-gated receptors are GABA receptors (GABAA and
GABAB).
Describe the process of how receptor proteins are synthesized and inserted into the
membrane. (From "Structure of muscle nicotinic ACh receptor" notes) - ANSWER
Receptor proteins are synthesized on ribosomes attached to the rough endoplasmic
reticulum (ER) membrane. They are inserted into the ER membrane co-translationally
using signal peptides and start/stop transfer sequences that act as transmembrane
domains. The receptors are then assembled in the ER and transported to the Golgi and
plasma membrane while maintaining their orientation.
What is the significance of the M2 membrane-spanning region in the nicotinic
acetylcholine receptor? (From "Structure of muscle nicotinic ACh receptor" notes) -
ANSWER The M2 membrane-spanning region lines the ion channel pore of the nicotinic
acetylcholine receptor. The structure of this region determines the ion selectivity and
current flow through the channel.
Explain the role of RNA editing in AMPA receptor function. (From "Structure of neuronal
nicotinic acetylcholine receptors" notes) - ANSWER The AMPA receptor subunit GluR2
undergoes post-transcriptional RNA editing at the Q/R site, converting a glutamine (Q)
codon to an arginine (R) codon. This editing renders AMPA receptors containing the
edited GluR2 subunit impermeable to calcium ions, preventing the stimulation of
calcium signaling pathways during basal excitatory synaptic transmission mediated by
AMPA receptors.
, How do NMDA receptors function as coincidence detectors? (From "Structure of
neuronal nicotinic acetylcholine receptors" notes) - ANSWER NMDA receptors function
as coincidence detectors because they require both the binding of glutamate and a
strong depolarizing stimulus to remove the voltage-dependent magnesium block from
the channel. This allows calcium influx through NMDA receptors only when the neuron is
strongly depolarized, such as by prior activation of AMPA receptors.
Describe the basic structure and components of G protein-coupled receptors (GPCRs).
(From "G protein-coupled receptors" notes) - ANSWER G protein-coupled receptors
(GPCRs) are seven-transmembrane proteins with an extracellular N-terminus containing
the neurotransmitter binding domain and an intracellular C-terminus that interacts with
G proteins through intracellular loops, particularly the third loop.
Explain the mechanism of GPCR signaling and how signal amplification occurs. (From
"G protein-coupled receptors" notes) - ANSWER Upon neurotransmitter binding, GPCRs
undergo a conformational change that activates their associated G proteins by
promoting the exchange of GDP for GTP on the Gα subunit. The active GTP-bound Gα
and Gβγ subunits dissociate and activate distinct effector proteins/enzymes that
produce second messengers. This cascade amplifies the signal, with one
neurotransmitter molecule leading to the production of hundreds of second
messengers.
What are chemogenetic tools like DREADDs, and how are they useful in studying
GPCRs? (From "G protein-coupled receptors" notes) - ANSWER Chemogenetic tools like
DREADDs (Designer Receptors Exclusively Activated by Designer Drugs) are modified
GPCRs that have been engineered to respond only to specific designer drugs and not
their endogenous neurotransmitter ligands. DREADDs allow researchers to selectively
activate or inhibit specific GPCR signaling pathways in vivo using these inert designer
drugs, enabling the study of GPCR functions in various biological processes.
Ligand-gated receptors have ____________ as a part of their structure. (From
"Ligand-gated neurotransmitter receptors" notes) - ANSWER Ion channels
The major excitatory receptor in the central nervous system that allows cation influx is
the ____________ receptor. (From "Ligand-gated neurotransmitter receptors" notes) -
ANSWER glutamate
2 With Complete Solutions
What is the primary function of ligand-gated neurotransmitter receptors? (From
"Ligand-gated neurotransmitter receptors" notes) - ANSWER The primary function of
ligand-gated neurotransmitter receptors is to control the flow of ions through their
receptor channels, producing excitatory or inhibitory synaptic potentials in response to
neurotransmitter binding.
Name the major excitatory and inhibitory ligand-gated receptors in the central nervous
system. (From "Ligand-gated neurotransmitter receptors" notes) - ANSWER The major
excitatory ligand-gated receptors in the central nervous system are nicotinic
acetylcholine receptors (nAChRs) and glutamate receptors (AMPA, NMDA, and
Kainate). The major inhibitory ligand-gated receptors are GABA receptors (GABAA and
GABAB).
Describe the process of how receptor proteins are synthesized and inserted into the
membrane. (From "Structure of muscle nicotinic ACh receptor" notes) - ANSWER
Receptor proteins are synthesized on ribosomes attached to the rough endoplasmic
reticulum (ER) membrane. They are inserted into the ER membrane co-translationally
using signal peptides and start/stop transfer sequences that act as transmembrane
domains. The receptors are then assembled in the ER and transported to the Golgi and
plasma membrane while maintaining their orientation.
What is the significance of the M2 membrane-spanning region in the nicotinic
acetylcholine receptor? (From "Structure of muscle nicotinic ACh receptor" notes) -
ANSWER The M2 membrane-spanning region lines the ion channel pore of the nicotinic
acetylcholine receptor. The structure of this region determines the ion selectivity and
current flow through the channel.
Explain the role of RNA editing in AMPA receptor function. (From "Structure of neuronal
nicotinic acetylcholine receptors" notes) - ANSWER The AMPA receptor subunit GluR2
undergoes post-transcriptional RNA editing at the Q/R site, converting a glutamine (Q)
codon to an arginine (R) codon. This editing renders AMPA receptors containing the
edited GluR2 subunit impermeable to calcium ions, preventing the stimulation of
calcium signaling pathways during basal excitatory synaptic transmission mediated by
AMPA receptors.
, How do NMDA receptors function as coincidence detectors? (From "Structure of
neuronal nicotinic acetylcholine receptors" notes) - ANSWER NMDA receptors function
as coincidence detectors because they require both the binding of glutamate and a
strong depolarizing stimulus to remove the voltage-dependent magnesium block from
the channel. This allows calcium influx through NMDA receptors only when the neuron is
strongly depolarized, such as by prior activation of AMPA receptors.
Describe the basic structure and components of G protein-coupled receptors (GPCRs).
(From "G protein-coupled receptors" notes) - ANSWER G protein-coupled receptors
(GPCRs) are seven-transmembrane proteins with an extracellular N-terminus containing
the neurotransmitter binding domain and an intracellular C-terminus that interacts with
G proteins through intracellular loops, particularly the third loop.
Explain the mechanism of GPCR signaling and how signal amplification occurs. (From
"G protein-coupled receptors" notes) - ANSWER Upon neurotransmitter binding, GPCRs
undergo a conformational change that activates their associated G proteins by
promoting the exchange of GDP for GTP on the Gα subunit. The active GTP-bound Gα
and Gβγ subunits dissociate and activate distinct effector proteins/enzymes that
produce second messengers. This cascade amplifies the signal, with one
neurotransmitter molecule leading to the production of hundreds of second
messengers.
What are chemogenetic tools like DREADDs, and how are they useful in studying
GPCRs? (From "G protein-coupled receptors" notes) - ANSWER Chemogenetic tools like
DREADDs (Designer Receptors Exclusively Activated by Designer Drugs) are modified
GPCRs that have been engineered to respond only to specific designer drugs and not
their endogenous neurotransmitter ligands. DREADDs allow researchers to selectively
activate or inhibit specific GPCR signaling pathways in vivo using these inert designer
drugs, enabling the study of GPCR functions in various biological processes.
Ligand-gated receptors have ____________ as a part of their structure. (From
"Ligand-gated neurotransmitter receptors" notes) - ANSWER Ion channels
The major excitatory receptor in the central nervous system that allows cation influx is
the ____________ receptor. (From "Ligand-gated neurotransmitter receptors" notes) -
ANSWER glutamate
