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What is the hyperpolarization that occurs after repolarizing phase of action potential?
Wiki User
∙ 11y ago
Hyperpolarization occurs because some of the K+ channels remain open to allow the Na+ channels to reset. This excessive amount of K+ causes hyperpolarization so the Na+ channels open to bring the potential back up to threshold.
Wiki User
∙ 12y ago
Wiki User
∙ 11y agoAfter the repolarizing phase of the action potential, membrane permeability to potassium ions remains high, which causes an "undershoot" or "afterhyperpolarization" phase until the membrane returns to its resting potential.
Wiki User
∙ 10y agoNeurons hyperpolarize after an action potential, entering what is called a "refractory period", so that repeated impulses from other neurons cannot cause overactivation of a given neural pathway. In this manner, ion channels close and the "overshoot" of hyperpolarization prevents the same relative level of depolarization to induce another action potential.
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What Hyperpolarizing membrane potential occurs in the postsynaptic membrane of a synapse?
Hyperpolarization means that the membrane potential becames more negative than the resting potential. This means that it is more difficult for an action potential to be triggered at the postsynaptic membrane. This occurs at inhibitory synapses. Hyperpolarization can be achieved by increasing the permeability of the membrane to potassium or chloride ions. If potassium permeability is increased more potassium ions will leave the cell, down their concentration gradient; if chloride permeability increases chloride ions will enter the cell down their concentration gradient. Both movements will make the inside of the cell more negative ie they will cause hyperpolarization.
Period of reploarization of the neuron during which it cannot respond to a second stimulus?
The absolute refractory period. This period occurs after the action potential has been initiated and is a result of inactivation of the sodium channels. These sodium channels would normally open up to allow sodium influx into the cell during an action potential. The absolute refractory period occurs during an ongoing action potential and is the period in which a subsequent action potential absolutely cannot be generated.This should not be confused with the relative refractory period which occurs immediately following the absolute refractory period (during membrane hyperpolarization). During this period a subsequent action potential is possible, but more difficult to attain.
Dendrites conduct both graded and action potential?
no, dendrites and cell bodies can only have graded potential. action potential only occurs in axons
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.
When the neuron is sufficiently stimulated this process occurs and triggers the action potential?
depolarization
What Hyperpolarizing membrane potential occurs in the postsynaptic membrane of a synapse?
Hyperpolarization means that the membrane potential becames more negative than the resting potential. This means that it is more difficult for an action potential to be triggered at the postsynaptic membrane. This occurs at inhibitory synapses. Hyperpolarization can be achieved by increasing the permeability of the membrane to potassium or chloride ions. If potassium permeability is increased more potassium ions will leave the cell, down their concentration gradient; if chloride permeability increases chloride ions will enter the cell down their concentration gradient. Both movements will make the inside of the cell more negative ie they will cause hyperpolarization.
Period of reploarization of the neuron during which it cannot respond to a second stimulus?
The absolute refractory period. This period occurs after the action potential has been initiated and is a result of inactivation of the sodium channels. These sodium channels would normally open up to allow sodium influx into the cell during an action potential. The absolute refractory period occurs during an ongoing action potential and is the period in which a subsequent action potential absolutely cannot be generated.This should not be confused with the relative refractory period which occurs immediately following the absolute refractory period (during membrane hyperpolarization). During this period a subsequent action potential is possible, but more difficult to attain.
An electrical impulse moving down an axon is called?
This is called action potential. Action potential is the change in electrical potential that occurs between the inside and outside of a nerve or muscle fiber when it is stimulated, serving to transmit nerve signals.
What event occurs as a result of a muscle action potential?
Reflex action
Triggering of the muscle action potential occurs after?
Triggering of the muscle action potential occurs after acetylcholine binds to chemically-gated channels in the end plate membrane.
Dendrites conduct both graded and action potential?
no, dendrites and cell bodies can only have graded potential. action potential only occurs in axons
What does it mean when a graded potential is called graded Why does it get this name?
Greded Is the membrane voltage change in response to a change in membrane permeability by adding or taking out gate channel. Depolarization occurs when there is a change in voltage towards a positive values b/c of opening up Na+ gate channels Hyperpolarization occurs when there is a more negative change in voltage due to opening up Cl- or K+ gate channels. It is called "graded" b/c you can open up some or many channels so the depolarization or hyperpolarization can be big or small Graded potentials start in one spot b/c of a change in permeability and then spreads to others as it travels; called local circuit current. The strength of graded potentials decreases as it spreads along the axon and eventually dies If you inject negative ions into the cell a hyperpolarization occurs If you inject positive ions into the cell a depolarization occurs If you inject a lot of positive charge the membrane depolarizes past 0 creates action potential and then comes back down' You get action potential once you pass the threshold voltage potential. Is a rapid depolarization which repolarizes
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.
When the neuron is sufficiently stimulated this process occurs and triggers the action potential?
depolarization
What is the sequence of electrical changes that occurs along the sacrolemma when a muscle fiber is stimulated?
action potential
What ion is the rising phase of the action potential?
Sodium ions are responsible for the rising phase of the action potential. This occurs when sodium channels open and sodium ions flow into the cell, causing depolarization.
During an action potential repolarization occurs as a result of?
potassium ions diffusion to the outside of the cell membrain,
