Firstly, a stimulus causes an influx of sodium ions into the axon. This causes further sodium voltage-gated ion channels to open, causing more sodium ions to move into the axon, down an electrochemical gradient, this depolarises the axon, if the influx of sodium ions reaches the threshold value of the axon then an action potential is produced. The sodium-voltage gated channels close when the potential of the axon reaches +40 mv. Potassium ion channels open, allowing K+ ions out of the axon and into surrounding tissue fluid. The electrical gradient is reversed and more potassium ions leave the axon. This is repolarisation. As more potassium ion channels are open compared to at resting potential, hyperpolarisation occurs. This is where the axon is more negative then usual. The sodium-potassium pump actively transports 3 Na+ ions out of the axon and 2K+ ions into the axon, with the use of ATP; allowing the resting potential to be reastablished.
It conveys a neural impulse along an axon.
It does so in a manner that is as strong at the end of the axon as at the beginning.
It only fires when enough input impulses sum up at the axon hillock (the beginning of the axon), and it does not vary in strength, so it's considered an 'all or nothing' signal; different intensities of sensory inputs are conveyed by different rates of firings, such that a strong sensory input will yield a fast series of action potentials, and a weak sensory input will yield just a few action potentials.
descibe the action potential the characteristics and the direction
When a stimulus stimulates a neuron above the threshold, the action potential is generated.
Action potential
The areas that have had the action potential are refractory to a new action potential.
Why does artifact always appear ahead of action potential?
Action Potential
It creates an action potential
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.
When a stimulus stimulates a neuron above the threshold, the action potential is generated.
Curare does NOT create an action potential. It binds to nicotinic acetylcholine receptors (which are primarily excitatory), and prevents the formation of an action potential.
It doesn't. I prevents an action potential from forming.
Action potential
action potential
Single action potentials follow the "all or none" rule. That is, if a stimulus is strong enough to depolarize the membrane of the neuron to threshold (~55mV), then an action potential will be fired. Each stimulus that reaches threshold will produce an action potential that is equal in magnitude to every other action potential for the neuron. Compound action potentials do not exhibit this property since they are a bundle of neurons and have different magnitudes of AP's. Thus compound action potentials are graded. That is, the greater the stimulus, the greater the action potential.
The areas that have had the action potential are refractory to a new action potential.
Why does artifact always appear ahead of action potential?
Action Potential
By self regenerating, they mean that when you start an action potential, it continues in proximal (nearby) tissue (e.g., nerve). The depolarization of the action potential continues along the nerve.