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Why does regeneration of the action potential occur in one direction?
Wiki User
∙ 11y ago
As the action potential passes an area on the axon, sodium channels are closed, preventing influx of more sodium ions. At the same time, voltage-sensitive potassium channels open, allowing the membrane potential to fall quickly. After this repolarization phase, membrane permeability to potassium remains high, allowing for the "afterhyperpolarization" phase.
During this entire period, while the sodium ion channels are forced closed, another action potential cannot be generated except by a much larger input signal.
This helps to prevent the action potential from moving backwards along the axon.
Wiki User
∙ 11y ago
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Does action potentials occur at nodes?
yes, the action potential occurs at the nodes of Ranvier -- there are Na (sodium channels) there that are depolarized/opened to maintain the action potential.
Where does the action potential occur on a neuron?
It starts at the axonal hillock and it propagates down the axon into the terminal boutons.
What can occur when the effects of one graded potential are added onto the effects produced by another graded potential which can lead to an action potential?
More sodium ions pile up (accumulate) at the axon hillock from the combination of the two (or more) graded potentials, which may be then be sufficient to initiate the action potential.
What is the stage in an action potential that immediately follow depolarisation?
After depolarization repolarization occur whcih then again lead to resting potentiol
A virus causes damage to the sodium channels of the postsynaptic neuron such that they open very slowly in response to a neurotransmitter How does this modify the generation of an action potential?
The sodium influx necessary for depolarization will occur more slowly making the action potential difficult to generate.
Is an action potential necessary for a nerve impulse to occur?
Yes, an action potential is needed for a nerve impulse to occur.
Is a action potential necessary for a nerve impulse to occur?
Yes, an action potential is needed for a nerve impulse to occur.
Does atrial systole occur before or after the firing of the sinoatrial node?
The SA node makes the action potential for the heart. Atrial systole must occur after the action potential.
Does action potentials occur at nodes?
yes, the action potential occurs at the nodes of Ranvier -- there are Na (sodium channels) there that are depolarized/opened to maintain the action potential.
List the events that occur in an action potential?
In simplest terms, the five stages of action potential are... A. Action Potential B. Depolarization C. Recovery Phase D. Refractory Period E. Hyper-polarization
How long does an action potential occur for?
2 milliseconds.
What are the events that must occur to generate action potential?
Local polarization is the first step. Next the generation and propagation of an action potential. Lastly repolarization has to take place.
What was Excitation and Inhibition about?
Excitation and Inhibition occur in the neurons. Excitation is when a neuron becomes depolarized and fires an action potential. Inhibition is when a neuron becomes hyperpolarized preventing it from firing an action potential.
Where does the action potential occur on a neuron?
It starts at the axonal hillock and it propagates down the axon into the terminal boutons.
What can occur when the effects of one graded potential are added onto the effects produced by another graded potential which can lead to an action potential.?
More sodium ions pile up (accumulate) at the axon hillock from the combination of the two (or more) graded potentials, which may be then be sufficient to initiate the action potential.
What can occur when the effects of one graded potential are added onto the effects produced by another graded potential which can lead to an action potential?
More sodium ions pile up (accumulate) at the axon hillock from the combination of the two (or more) graded potentials, which may be then be sufficient to initiate the action potential.
What is the stage in an action potential that immediately follow depolarisation?
After depolarization repolarization occur whcih then again lead to resting potentiol
