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Hello students, in this video we will discuss about sodium and potassium channels.
00:15
It play a crucial role in enabling neurons to generate and propagate action potentials.
00:40
They also contribute to ensuring that the action potential flow only in one direction.
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Here is an explanation of their involvement.
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First is resting membrane potential.
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Neurons have a resting membrane potential typically around minus 70 millivolts which is maintained by the uneven distribution of ions across the neuronal membrane.
01:40
At rest there is a higher concentration of sodium ions outside the neuron and a higher concentration of potassium ions inside the neurons.
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Second is depolarization and initiation of action potential.
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When a neuron receives a stimulus or reaches a threshold level of depolarization, sodium channels of the neuronal membrane open.
02:53
This allows an influx of sodium ions into the neuron leading to depolarization.
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As the membrane potential reaches a certain threshold that is around minus 55 millivolt to minus 50 millivolt, it triggers an action potential.
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And next is rising phase of action potential.
04:00
During the rising phase, the opening of sodium channels causes a rapid influx of sodium ions into the neuron...