Sydney Holst
When certain chemicals interact with a neuron, they alter the balance of ions inside and outside the cell. If this change reaches threshold, it sends a signal down the neuron’s membrane to the axon. At the axon, the neuron fires the signal to a neighboring neuron, and the process repeats.
Once the electrical potential of Neuron A (presynaptic neuron) reaches -60mV the sodium and potassium channels in the neuron open at the beginning of the axon. The influx of positive sodium ions into the cell makes the inside of the cell more positive and leaves the outside of the cell more negative. The cell is at rest at -70mV and as it gets more positive, it reaches threshold (gets more excited). This change in electrical potential also excites neighboring sodium and potassium channels to open up in a chain reaction, which is known as the action potential. Because the sodium influx at the beginning is faster than the outflux of potassium, the inside of axon at the beginning of the excitation is negative while the outside is positive. But a little after the first sodium and potassium ion channels open up, the outflux of potassium becomes great enough that the outside of the cell becomes …show more content…
The cascade of sodium/potassium ion channels opening up in a chain reaction that progresses away from the body of Neuron A along its axon eventually reaches the terminal
When certain chemicals interact with a neuron, they alter the balance of ions inside and outside the cell. If this change reaches threshold, it sends a signal down the neuron’s membrane to the axon. At the axon, the neuron fires the signal to a neighboring neuron, and the process repeats.
Once the electrical potential of Neuron A (presynaptic neuron) reaches -60mV the sodium and potassium channels in the neuron open at the beginning of the axon. The influx of positive sodium ions into the cell makes the inside of the cell more positive and leaves the outside of the cell more negative. The cell is at rest at -70mV and as it gets more positive, it reaches threshold (gets more excited). This change in electrical potential also excites neighboring sodium and potassium channels to open up in a chain reaction, which is known as the action potential. Because the sodium influx at the beginning is faster than the outflux of potassium, the inside of axon at the beginning of the excitation is negative while the outside is positive. But a little after the first sodium and potassium ion channels open up, the outflux of potassium becomes great enough that the outside of the cell becomes …show more content…
The cascade of sodium/potassium ion channels opening up in a chain reaction that progresses away from the body of Neuron A along its axon eventually reaches the terminal