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Why can't an action potential be generated during the absolute refractory period?
Wiki User
∙ 13y ago
Action potentials cannot be generated during the absolute refractory period, as not enough ion channels are able to respond to the stimulus, no matter how large it is. Using Na+ fast channels as an example, during depolarization the "gate" of the channel is opened, allowing for Na+ influx into the cell. However, during the repolarization phase, a second "gate" marks the closure of the cell, preventing any further movement of ions into the cell. However, this also means that the channel is unable to open again until the second gate is removed, and the first gate returns back into place.
Wiki User
∙ 13y ago
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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.
What is The time an action potential begins until the resting potential has stabilized is?
1/2500 sec is the absolute refractory period.
Why is the cardiac action potential longer?
The reason why cardiac muscle has a longer action potential is to extend the absolute refractory period to prevent another action potential. If too many action potentials stimulate the cardiac muscle it can get into tetanus which keeps the heart continuously contracted without relaxation.
The action potential is generated when a stimulus?
When a stimulus stimulates a neuron above the threshold, the action potential is generated.
Do axons carry action potentials away from the cell body?
The areas that have had the action potential are refractory to a new action potential.
What is the absolute refractory period?
Absolute Refractory Period:It is the interval during which a second action potential absolutely cannot be initiated, no matter how large a stimulus is applied.ORAfter repolarization there is a period during which a second action potential cannot be initiated, no matter how large a stimulus current is applied to the neuron. This is called the absolute refractory period, and it is followed by a relative refractory period, during which another action potential can be generated
2 Define refractory period and differentiate between absolute and relative refractory periods?
refractory period is the interval between action potential , the absolute refractory period is the period in which second action potential can not be initiated but in relative refractory period the second action potential can be initiated by the more strong stimulus.
Absolute refractory period relative refractory period?
In absolute refractory period, none of channels are reconfigured, so that second active potential cannot be generated no matter how large the stimulus current is applied to the neuron. In contrast, in relative refractory period, some but not all of channels are reconfigured, another action potential can be generated but only by a greater stimulus current thatn that originally needed.
What causes absolute refractory period?
The absolute refractory period coincides with pretty much the entire duration of the action potential. It is caused by the inactivation in neurons.
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.
A period after an initial stimulus when a neuron is not sensitive to another stimulus is the?
After the generation and propagation of an action potential along a neuron, the cell becomes depolarized to the point where there is no potential for further signaling until the cell re-polarizes through the action of ion pumps. This very brief period is called the refractory state.
What is The time an action potential begins until the resting potential has stabilized is?
1/2500 sec is the absolute refractory period.
What is the cause of the relative refractory period?
The Refractory period is when a second action potential is possible, but unlikely; second action potential only if the stimulus is sufficiently strong. The refractory period helps to prevent backflow of Sodium.
Why is the cardiac action potential longer?
The reason why cardiac muscle has a longer action potential is to extend the absolute refractory period to prevent another action potential. If too many action potentials stimulate the cardiac muscle it can get into tetanus which keeps the heart continuously contracted without relaxation.
When can a second nerve impulse cannot be generated?
The generation of a second action in some neurons can only happen after a refractory period, when the membrane potential has returned it's base level or even more negative. This is because some types of Na+ channels inactivate at a positive potential and then require a negative potential to reset. Other neurons have other types of channels and can fire multiple action potentials to a single depolarization.
The action potential is generated when a stimulus?
When a stimulus stimulates a neuron above the threshold, the action potential is generated.
Do axons carry action potentials away from the cell body?
The areas that have had the action potential are refractory to a new action potential.
