NUR 751 Neuromuscular, Neurophysiology, and
NMBD–Questions and Answers | 2026 Update |
100% Correct.
Types of subunits on nicotinic ACh receptors. Difference between adult and fetal?
Adult - 2alpha, 1 beta, 1 delta, 1 epsilon
Fetal- gamma instead of epsilon
What are the two calcium channels in muscle that participate in neuromuscular
transmission?
dihydropyridine (DHP in T tubules)
ryanodine (in sarcoplasmic reticulum)
Malignant hyperthermia is caused by the failure of ___________ leading to sustained
muscle contraction
calcium ion pump
dysfunction of ryanodine
The interaction of DHP and ryanodine releases _________
calcium from SR
How many alpha subunits does ACh bind to?
How many do non-depolarizing paralytics need to bind to?
Depolarizing?
,ACh: 2
non-depolarizing: 1 or both
depolarizing: 1
Succinylcholine (SCh) is structurally ____________. Where does stimulate receptors?
2 ACh together
-NMJ
-nicotinic ganglionic receptors
-muscarinic autonomic sites
What type of receptors does succinylcholine bind to?
nicotinic acetylcholine receptors (nAChR)
ACh is broken down by_________
acetylcholinesterase
Succinylcholine is broken down by _________
butyrylcholinesterase
(plasma cholinesterase via hydrolysis)
3 types of muscle
smooth
cardiac
skeletal
,Differences between red and white motor units
red - small, slow, stamina
white - large, fast, easily fatigued
What is a synapse? What happens here?
-site of transmission of an action potential from the presynaptic membrane to the postsynaptic
membrane
-afferent action potential arrives at voltage gated calcium channel
-influx of calcium, binds to release apparatus on axonal and vesicular membranes and triggers
fusion of vesicle to the cell membrane - exocytosis
-neurotransmitter released into synaptic cleft and binds to postsynaptic membrane,
stimulating action potential in the dendrite of the efferent nerve
Presynaptic membrane contains vesicles filled with _________ and a _________. When are
they released?
-neurotransmitters
-reuptake pump
-arrival of action potential
neuromuscular junction (NMJ). What happens here at its most basic? What are the 3
areas?
-transmits electrical impulses from nerve terminal to skeletal muscle through ACh
, -presynaptic nerve terminal
-synaptic cleft
-postsynaptic muscle membrane
What is ACh broken down to?
acetyl CoA and choline
choline is recycled
Fetal nicotinic ACh receptors are __________ to non-depolarizing paralytics and
__________ to depolarizing
resistant to non-depolarizing
sensitive to depolarizing
Non-depolarizing NMBD are _______ _________(competitive/non-competitive;
agonist/antagonist)
competitive antagonists
compete with ACh at receptor
synaptic plasticity
-ability of individual synaptic junctions to respond to either use or disuse
-synthesis, storage, release of ACh
-binding of ACh to post-synaptic nAChR leading to action potential
-rapid hydrolysis of ACh by acetylcholinesterase in synaptic cleft
-Adaptation of motor contractile proteins to functional demands
NMBD–Questions and Answers | 2026 Update |
100% Correct.
Types of subunits on nicotinic ACh receptors. Difference between adult and fetal?
Adult - 2alpha, 1 beta, 1 delta, 1 epsilon
Fetal- gamma instead of epsilon
What are the two calcium channels in muscle that participate in neuromuscular
transmission?
dihydropyridine (DHP in T tubules)
ryanodine (in sarcoplasmic reticulum)
Malignant hyperthermia is caused by the failure of ___________ leading to sustained
muscle contraction
calcium ion pump
dysfunction of ryanodine
The interaction of DHP and ryanodine releases _________
calcium from SR
How many alpha subunits does ACh bind to?
How many do non-depolarizing paralytics need to bind to?
Depolarizing?
,ACh: 2
non-depolarizing: 1 or both
depolarizing: 1
Succinylcholine (SCh) is structurally ____________. Where does stimulate receptors?
2 ACh together
-NMJ
-nicotinic ganglionic receptors
-muscarinic autonomic sites
What type of receptors does succinylcholine bind to?
nicotinic acetylcholine receptors (nAChR)
ACh is broken down by_________
acetylcholinesterase
Succinylcholine is broken down by _________
butyrylcholinesterase
(plasma cholinesterase via hydrolysis)
3 types of muscle
smooth
cardiac
skeletal
,Differences between red and white motor units
red - small, slow, stamina
white - large, fast, easily fatigued
What is a synapse? What happens here?
-site of transmission of an action potential from the presynaptic membrane to the postsynaptic
membrane
-afferent action potential arrives at voltage gated calcium channel
-influx of calcium, binds to release apparatus on axonal and vesicular membranes and triggers
fusion of vesicle to the cell membrane - exocytosis
-neurotransmitter released into synaptic cleft and binds to postsynaptic membrane,
stimulating action potential in the dendrite of the efferent nerve
Presynaptic membrane contains vesicles filled with _________ and a _________. When are
they released?
-neurotransmitters
-reuptake pump
-arrival of action potential
neuromuscular junction (NMJ). What happens here at its most basic? What are the 3
areas?
-transmits electrical impulses from nerve terminal to skeletal muscle through ACh
, -presynaptic nerve terminal
-synaptic cleft
-postsynaptic muscle membrane
What is ACh broken down to?
acetyl CoA and choline
choline is recycled
Fetal nicotinic ACh receptors are __________ to non-depolarizing paralytics and
__________ to depolarizing
resistant to non-depolarizing
sensitive to depolarizing
Non-depolarizing NMBD are _______ _________(competitive/non-competitive;
agonist/antagonist)
competitive antagonists
compete with ACh at receptor
synaptic plasticity
-ability of individual synaptic junctions to respond to either use or disuse
-synthesis, storage, release of ACh
-binding of ACh to post-synaptic nAChR leading to action potential
-rapid hydrolysis of ACh by acetylcholinesterase in synaptic cleft
-Adaptation of motor contractile proteins to functional demands
