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18 terms

Action potential

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-70, +30
The action potential changes the membrane potential from ______mV (resting) to ____mV and back again to the resting membrane potential?
Na+, k+, and voltage-gated
A change in membrane permeability first to ___then to ___due to the opening of what type of ion channel?
Axon hillock
Where is the density of voltage-gated Na+ channels the greatest?
Dendrites and cell body
What areas of the neuron generate signals that open these voltage-gated channels?
Depolarize
Opening of these channels causes the membrane to ___(voltage change)
Threshold, action potential
If the membrane reaches the trigger point, known as _____what electrical potential will be generated?
Na+, Na+
During the depolarized phase, voltage-gated ____channels open and ____enters the cell?
Inactivtion of voltage-gated Na+ channels and Opening of voltage-gated K+ channels
What are the two processes that stop the potential from rising above +30 mV?
Repolarize
The opening of voltage-gated K+ channels cause the membrane to ____?
Out of the cell
Does K+ move into or out of the cell?
Hyperpolarization
If the membrane potential becomes more negative than -70 mV, this is called ___?
Slow decline
This potential is caused by what characteristic of K+ permeability?
N+, absolute refractory
After an action potential, the neuron cannot generate another action potential because____channels are inactive. This period is called the ____period?
Relative refractory, more
During the ___period, the cell can generate another action potential but only if the membrane is____(more or less) depolarized.
Increased diameter and pressure of mylein
Conduction velocity along the axon is increased by what two characteristics?
Saltatory
Conduction along a myelinated axon is called_____conduction?
Multiple sclerosis
Name the disease whose symptoms include loss of vision and increasing muscle weakness?
Myelin sheaths of CNS axons/Low voltage-gated channels between the nodes of Raniver
What does Multiple sclerosis destroy? How does it stop action potential?