The neural activity progresses as if it were a wave (the effect moves but the nerve, of course does not). As the wave progresses it depolarizes the nerve surface, opens Na+ channels and activates the nerve surface as it goes forward. One effect of the firing however is that the Na+ channels inactivate and enter a refractory period in which they will not reopen. This essential drives the propagation wave in one direction only.
If the nerve were to be simultaneously stimulated at both ends the two waves would meet and then activity would cease. Neither wave would be able to overcome the refractory membrane that the other wave had passed over.
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Nerve conduction involves the transmission of electrical impulses along the length of a nerve fiber. When a nerve is stimulated, sodium ions rush into the nerve cell, causing a change in electrical charge. This creates an action potential that travels down the nerve fiber, activating adjacent areas and allowing the signal to be transmitted. Once the impulse reaches its destination, neurotransmitters are released to stimulate the next nerve cell or muscle fiber.
Vagal escape occurs when the parasympathetic nervous system, specifically the vagus nerve, fails to regulate the heart rate and the heart muscle is instead stimulated by other mechanisms. This can happen in situations where there is a prolonged increase in sympathetic nerve activity or when there is a dysfunction in the parasympathetic nervous system.
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.
required to maintain nerve fiber sheath
What is the difference between the contour and magnitude of single nerve fiber and nerve trunk?
they go nerve to nerve till it gets to the brain first is a nerve then the dendrite then the brian
The resting nerve cell is not being stimulated to send a nerve impulse
When a muscle is stimulated not all motor units in the nerve are fired. More muscle fibers are stimulated, however and smaller nerves are stimulated before larger ones.
When you have a fresh wound you have exposed nerve endings. When these nerve endings are stimulated it is sensed by your brain as pain.
A neuron is an excitable nerve cell that sends electrical signals when stimulated
The reason why a peripheral nerve such as the sciatic nerve can contain nerve fiber from several spinal nerves is owing to nerve plexuses. These are networks of nerves all tangled together and found mostly in the limbs.