: the period immediately following the firing of a nerve fiber when it cannot be stimulated no matter how great a stimulus is applied .
What is the absolute refractory period quizlet?
The period from the initiation of the action potential to immediately after the peak is referred to as the absolute refractory period (ARP) This is the time during which another stimulus given to the neuron will not lead to a second action potential. ... The absolute refractory period takes about 1-2 ms .
What is meant by the absolute refractory period and what causes it?
The cell membrane cannot immediately produce a second AP. The period of time when the majority of voltage-gated Na + channels are inactivated defines the ABSOLUTE REFRACTORY PERIOD, when no amount of depolarizing current can cause an action potential .
What is the absolute and relative refractory period?
Absolute: Is the period of time during which a second action potential ABSOLUTELY cannot be initiated , no matter how large the applied stimulus is. Relative: Is the interval immediately following the Absolute Refractory Period during which initiation of a second action potential is INHIBITED, but not impossible.
What best describes the absolute refractory period?
Explanation: Absolute refractory period of a neuron is the period of time during which no amount of external stimulus will generate an action potential . Relative refractory period is the period of time during which only a large stimulus will generate an action potential.
What is the importance of the absolute refractory period?
Absolute refractory periods help direct the action potential down the axon , because only channels further downstream can open and let in depolarizing ions. Relative refractory period: during this time, it is really hard to send an action potential.
What is the refractory period and why is it important?
The refractory period limits the rate at which action potentials can be generated , which is an important aspect of neuronal signaling. Additionally, the refractory period facilitates unidirectional propagation of the action potential along the axon.
What happens during a neuron’s refractory period?
By definition, the refractory period is a period of time during which a cell is incapable of repeating an action potential . In terms of action potentials, it refers to the amount of time it takes for an excitable membrane to be ready to respond to a second stimulus once it returns to a resting state.
What happens during the relative refractory period?
During the relative refractory period, a stronger than normal stimulus is needed to elicit neuronal excitation . After the absolute refractory period, Na + channels begin to recover from inactivation and if strong enough stimuli are given to the neuron, it may respond again by generating action potentials.
What does refractory period mean in psychology?
psychological refractory period (PRP)
the period after response to a stimulus during which response to a second stimulus, presented shortly after the first , is delayed.
What is ERP in heart?
In electrocardiography, during a cardiac cycle, once an action potential is initiated, there is a period of time that a new action potential cannot be initiated. This is termed the effective refractory period (ERP) of the tissue.
Which channel gets open up after a stimulus is applied?
The opening of sodium channels allows nearby sodium channels to open, allowing the change in permeability to spread from the dendrites to the cell body.
What is an example of a refractory period?
An example of the refractory period is when talking on the phone while driving causes you to react slower to seeing a stopped car in front of you . So the next time you see a friend texting and driving, remind them that by doing so they are slowing their reaction time, which could be dangerous.
What is the most common type of neuron?
Interneurons . Interneurons are neural intermediaries found in your brain and spinal cord. They’re the most common type of neuron. They pass signals from sensory neurons and other interneurons to motor neurons and other interneurons.
What are Ranvier’s nodes?
Node of Ranvier, periodic gap in the insulating sheath (myelin) on the axon of certain neurons that serves to facilitate the rapid conduction of nerve impulses . ... Nodes of Ranvier are approximately 1 μm wide and expose the neuron membrane to the external environment.
Does myelination increase resistance?
Yet, the main purpose of myelin likely is to increase the speed at which neural electrical impulses propagate along the nerve fiber. ... Myelin in fact decreases capacitance and increases electrical resistance across the cell membrane (the axolemma) thereby helping to prevent the electric current from leaving the axon.
