Font size
WorksheetsUnit 4 Lecture 2 Review- Steps of a nerve impulse
Total questions: 42
Worksheet time: 24mins
When a neuron is depolarized, what are the first channels to open?
Sodium
Calcium
Potassium
Sodium potassium pump
When a neuron is resting, the inside of the axon has a ____________ charge.
positive
negative
When a neuron is at REST,
the inside of the neuron is negatively charged compared to the outside.
the inside of the neuron is positively charged compared to the outside.
there is no charge difference established
none of these are true
Depolarization occurs when
sodium channels open
potassium channels open
sodium channels close
potassium channels close
Based on the descriptions in the image, the ion channels that open during an action potential are which kind of channel?
Ligand-gated
Mechanically-gated
Voltage-gated
Always open
What is structure Z?
Dendrite
Axon terminal
Neurotransmitters
Synapse
Remember that neurons send signals from one neuron to the next... and so if we know how the action potential travels down a single neuron, and we know what happens when action potentials reach the end of a motor neuron, what do you think structure W might be if instead of stimulating a muscle, the neuron was simply communicating with another neuron?
axon terminal
dendrite
neurotransmitters
synapse
What is the normal resting potential of a neuron cell membrane?
+40 mV
-30 mV
+55 mV
-70 mV
In resting potential, neurons have more _________ on the outside of the cell membrane.
K+
NaCl
Na+
Ca2+
At what stage are both ions present in large concentrations INSIDE the neuron?
Depolarization
Repolarization
Hyperpolarization
Resting Potential
When is the potassium channel open?
during rest only
during repolarization only
during depolarization only
all the time
As the neuron fires, there's a reversal in _____ as the axon undergoes ________.
direction, depolarization
charge, depolarization
direction, repolarization
charge, repolarization
Occurs when sodium voltage-gated channels open and sodium rushes into the axon changing the membrane potential from -55mV to +40mV.
Depolarization
Hyperpolarization
Repolarization
Summation
Resting-State
Occurs when sodium voltage-gated channels close and potassium voltage-gated channels open. Potassium rushes out of the axon changing the membrane potential from +40mV to -70mV.
Depolarization
Hyperpolarization
Repolarization
Resting-State
Occurs when both voltage-gated channels remain closed and the sodium-potassium pump moves 3Na out and 2K in maintaining a membrane potential of -70mV.
Depolarization
Hyperpolarization
Repolarization
Resting-State
What maintains the resting membrane potential in a neuron?
sodium-potassium pumps
sodium channels
potassium channels
gravity
Depolarization is occurring at
A
B
C
D
When a membrane potential reaches +30mV, ________ channels open, ________ occurs, and ________ channels close.
Sodium, depolarization, potassium
Potassium, depolarization, sodium
sodium, repolarization, potassium
potassium, repolarization, sodium
Why is -55 mV a significant number?
This is the largest charge achieved during an action potential
This is the threshold required to complete an action potential
This is the resting charge of a neuron
This is the charge when all the sodium is inside the cell
In resting potential, neurons have more _________ on the outside of the cell membrane.
K+
Na+
Ca+
sodium channels
Which one of the following is involved in maintaining a resting membrane potential?
Na+/K+ ATPase pump moves 3Na+ in for every 2K+ out
Na+/K+ ATPase pump moves 3K+ in for every 2Na+ out
Na+/K+ ATPase pump moves 3Na+ out for every 2K+ in
Na+/K+ ATPase pump moves 3K+ out for every 2Na+ in
Which of the following restores the resting membrane potential in a neurone?
I. Na+ channels opening
II. K+ channels closing
III. The Na+/K+ ATP pump
I and II only
II and III only
I and III only
III only
Which of the following is/are true of repolarisation?
Na+ channels close
K+ diffuses into the neuron
The membrane potential becomes more negative
Na+ diffuses out of the neuron
Action potentials run along the ______ from ______ to ________.
axon, dendrites, axon terminals
axon, axon terminals, dendrites
dendrites, axon, axon terminals
axon terminals, axon, dendrites
The charge on sodium and potassium ions
both are negative
Na is negative and K is positive
both are positive
Na is positive and K is negative
Where are the Na/K pumps, Na channels & K channels found?
in the terminal buttons
on each dendrite
along axon, buried in myelin sheath
along axon, in Nodes of Ranvier
The term central nervous system refers to the:
autonomic and peripheral nervous systems
brain, spinal cord, and cranial nerves
brain and cranial nerves
spinal cord and spinal nerves
brain and spinal cord
The Schwann cell forms a myelin sheath around the:
dendrites
cell body
nucleus
axon
nodes of Ranvier
The neuron processes that normally receive incoming stimuli are called:
axons
dendrites
neurolemmas
Schwann cells
satellite cells
Impulse conduction is fastest in neurons that are:
myelinated
unmyelinated
sensory
motor
cerebral
The gap between two communicating neurons is termed:
synaptic cleft
cell body
effector
Schwann cell
node of Ranvier
An action potential is caused by an influx of these ions into the cell:
potassium
sodium
calcium
magnesium
both potassium and sodium
Which of the following is the correct sequence in a typical reflex arc?
effector, afferent neuron, integration center, efferent neuron, receptor
receptor, afferent neuron, integration center, efferent neuron, effector
effector, efferent neuron, integration center, afferent neuron, receptor
receptor, efferent neuron, integration center, afferent neuron, effector
receptor, afferent neuron, efferent neuron, integration center, effector
The substance that is released at axonal endings to propagate a nervous impulse is called:
an ion
nerve glue
a neurotransmitter
the sodium-potassium pump
an action potential
Which one of the following is the correct sequence of events:
- the membrane becomes depolarized
- sodium channels open and sodium ions diffuse in
- the membrane become repolarized
- potassium channels open and potassium ions diffuse inward while sodium is actively transported out of the cell
3,2,4,1
2,1,4,3
2,1,3,4
1,2,4,3
4,1,3,2
Depolarization occurs because
more Na+ diffuse into the cell than K+ diffuse out of it.
both Na+ and K+ diffuse into the cell.
more K+ diffuse out of the cell than Na+ diffuse into it.
more K+ diffuse into the cell than Na+ diffuse out of it.
Repolarization occurs because
more Na+ diffuse into the cell than K+diffuse out of it.
both Na+ and K+ diffuse into the cell.
more K+ diffuse out of the cell than Na+ diffuse into it.
more K+ diffuse into the cell than Na+diffuse out of it.
During depolarization, which of the following statements about voltage-gated ion channels is TRUE?
Na+ gates open before K+ gates
K+ gates open while Na+ gates remain closed
K+ gates open before Na+ gates
Na+ and K+ gates open at the same time
Action potential propagation occurs in both directions along the axon.
True
False
