the nerve impulse
The nerve impulse
The information is transmitted by polarity changes in the membranes of cells due to the presence of neurotransmitters that alter the ionic concentration inside the cell.
Moreover, inside the neuron proteins and ions are negatively charged . This difference in ion concentration also produces a potential difference between the outer membrane and within the cell . The value reached is about -70 millivolts (negative inside with respect to the value of positive charges outside ) .
This variation between the exterior and interior is achieved by the operation of the sodium / potassium (Na + / K +)
The pump Na + / K + ATP spends . Expels three sodium ions that were in the interior of the neuron and introduces two potassium ions were outside. Sodium ions can not reenter the neuron, because the membrane is impermeable to sodium. Therefore, the concentration of sodium ions on the outside is high. Furthermore, three positive charges are lost every time the pump operates Na + / K + , although two charges entering potassium . This makes the outside has more positive charges on the interior, creating a potential difference . It is said that the neuron is in resting potential , ready to receive a nerve impulse .
When the nerve impulse reaches a neuron at rest the membrane is depolarized , opening channels for sodium. As the sodium concentration is very high in the outside when the sodium channels are open to the polarity is reversed , so that the interior of the neuron reaches a value electropositive with respect to the outside.
If depolarization causes a change in potential of 120 millivolts more than we had the inside is said to have reached the action potential, which is the transmission of the nerve impulse to the next neuron, because it creates the conditions in the cell interior to be able to secrete a neurotransmitter to the area of contact between neurons.
The nerve impulse is the law of all or nothing . This means that if the
The information is transmitted by polarity changes in the membranes of cells due to the presence of neurotransmitters that alter the ionic concentration inside the cell.
Moreover, inside the neuron proteins and ions are negatively charged . This difference in ion concentration also produces a potential difference between the outer membrane and within the cell . The value reached is about -70 millivolts (negative inside with respect to the value of positive charges outside ) .
This variation between the exterior and interior is achieved by the operation of the sodium / potassium (Na + / K +)
The pump Na + / K + ATP spends . Expels three sodium ions that were in the interior of the neuron and introduces two potassium ions were outside. Sodium ions can not reenter the neuron, because the membrane is impermeable to sodium. Therefore, the concentration of sodium ions on the outside is high. Furthermore, three positive charges are lost every time the pump operates Na + / K + , although two charges entering potassium . This makes the outside has more positive charges on the interior, creating a potential difference . It is said that the neuron is in resting potential , ready to receive a nerve impulse .
When the nerve impulse reaches a neuron at rest the membrane is depolarized , opening channels for sodium. As the sodium concentration is very high in the outside when the sodium channels are open to the polarity is reversed , so that the interior of the neuron reaches a value electropositive with respect to the outside.
If depolarization causes a change in potential of 120 millivolts more than we had the inside is said to have reached the action potential, which is the transmission of the nerve impulse to the next neuron, because it creates the conditions in the cell interior to be able to secrete a neurotransmitter to the area of contact between neurons.
The nerve impulse is the law of all or nothing . This means that if the