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What is the primary action during depolarization of an action potential?
Wiki User
∙ 11y ago
Sodium ions flow into the neuron via voltage-gated sodium ion channels, driving the membrane potential into the positive. Beyond the threshold, more sodium ion channels are opened, causing the influx of sodium further downstream, and the process repeats, propagating the action potential down the axon.
Wiki User
∙ 11y ago
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What happens in the neurolemma as the result of an action potential?
It provides insulation to the axons and dendrites during depolarization or action potential.
What ion is rapidly moving into the cell during the depolarization period of an action potential?
Sodium.A positive ion (cation) that enters the cell (influx) rapidly when the membrane threshold is reached and the voltage gated sodium channels open.This occurs during the rising phase of an action potential, i.e. membrane depolarization beyond the threshold for activation.
What is the primary feature of a neuron that prevents the action potential from traveling back from where it just passed?
Antidromic conduction, or the process of an action potential traveling backwards, is possible. However, regardless of the direction of the action potential, it is propagated by voltage-gated ion channels. Whenever these channels open, there is a sudden exchange of ions, after which the channels snap shut. During this period, known as the refractory period, the channels will not reopen, and thus an action potential will not be able to reverse direction.
What is the interval called during which a neuron is dormant after an action potential has been completed?
Resting potential
What are the Stages of nerve impulses?
The action potential has 5 main phases:1) stimulation/rising phase - depolarization caused by influx of sodium ions at the axon hillock; potential increases from a resting potential of -70 mV2) peak phase - depolarization and membrane potential reaches a peak, with sodium channels open maximally, at about +40 mV3) falling phase - potassium channels open in response, causing a subsequent reduction in membrane potential, and the neuron begins to repolarize4) hyperpolarization/undershoot phase - more potassium channels stay open after sodium channels close, causing a hyperpolarization of the neuronal membrane, bringing the potential down below its initial resting potential (below -70 mV)5) refractory phase - potassium channels begin to close, allowing the membrane potential to revert back to the resting potential of -70 mV; during this phase, the probability of the nerve being able to refire is extremely low, thus allowing for a delay between action potentials
Which is the first step in a neuron production of an action potential?
Depolarization is the first event in action potential. During depolarization, the sodium gates open and the membrane depolarizes.
What happens in the neurolemma as the result of an action potential?
It provides insulation to the axons and dendrites during depolarization or action potential.
During depolarization of action potential the outer part of axon becomes?
Negative
What ion is rapidly moving into the cell during the depolarization period of an action potential?
Sodium.A positive ion (cation) that enters the cell (influx) rapidly when the membrane threshold is reached and the voltage gated sodium channels open.This occurs during the rising phase of an action potential, i.e. membrane depolarization beyond the threshold for activation.
What channels are open during depolarization and during repolarization?
During depolarization Na channels are open During repolarization K channels are open
What is the Difference between a receptor and an action potential?
action potential has a threshold stimulus and depolarization is just change in membrae potential where inside becomes for positive relative to outside. The AP has the ability to actually transmit info over long distance in axons once threshhold stimulus/depolarization is reached
What is the primary feature of a neuron that prevents the action potential from traveling back from where it just passed?
Antidromic conduction, or the process of an action potential traveling backwards, is possible. However, regardless of the direction of the action potential, it is propagated by voltage-gated ion channels. Whenever these channels open, there is a sudden exchange of ions, after which the channels snap shut. During this period, known as the refractory period, the channels will not reopen, and thus an action potential will not be able to reverse direction.
What is the interval called during which a neuron is dormant after an action potential has been completed?
Resting potential
Is the Nernst potential of Sodium achieved during the action potential?
the Nernst potential of Sodium is +60mV. most action potentials do not reach +60mV at peak depoloarization. http://openwetware.org/images/thumb/a/a6/Action-potential.jpg/300px-Action-potential.jpg.png
What are the Stages of nerve impulses?
The action potential has 5 main phases:1) stimulation/rising phase - depolarization caused by influx of sodium ions at the axon hillock; potential increases from a resting potential of -70 mV2) peak phase - depolarization and membrane potential reaches a peak, with sodium channels open maximally, at about +40 mV3) falling phase - potassium channels open in response, causing a subsequent reduction in membrane potential, and the neuron begins to repolarize4) hyperpolarization/undershoot phase - more potassium channels stay open after sodium channels close, causing a hyperpolarization of the neuronal membrane, bringing the potential down below its initial resting potential (below -70 mV)5) refractory phase - potassium channels begin to close, allowing the membrane potential to revert back to the resting potential of -70 mV; during this phase, the probability of the nerve being able to refire is extremely low, thus allowing for a delay between action potentials
What changes occur in the neuron during an action potential?
During an action potential, the neuron undergoes a rapid change in membrane potential as sodium ions rush into the cell, leading to depolarization. Subsequently, potassium ions move out of the cell, repolarizing the membrane back to its resting state. This rapid change in membrane potential allows for the transmission of electrical signals along the neuron.
What is the process called when sodium NA is pumped out of a nerve cell?
during action potentials, sodium and potassium cross the membrane of the synapse after the threshold of membrane potential is reached. There, sodium leaves the synapse and the membrane potential is now positive. this is known as depolarization. then during repolarization, the sodium channels close and the potassium channels open to stabilize the membrane potential. during this time, a second action potential cannot occur and this is an evolutionary advantage because it allows rest in the nerve cells and it allows the membrane potential to equalize.
