Action Potential Research Paper

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Before a neuron reaches an action potential, it is at resting potential. At resting potential, there is a higher concentration of sodium outside the cell than inside. Sodium would like to move down its concentration gradient, but can’t because there is a membrane in the way. Similarly, there is a high concentration of potassium inside the cell and a lower concentration of potassium outside the cell. Potassium would like to move down its concentration gradient, but can’t because of the membrane. An action potential occurs when a neuron sends information down an axon, away from the cell body. The action potential is the “firing” of the cell. It is an all or nothing potential, meaning it either occurs at full strength or does not occur at all.…show more content…
Once the threshold is met, the permeability of the membrane shifts towards sodium and sodium channels open. This causes sodium ions to diffuse into the cell. This sodium influx is brought about both by the sodium concentration gradient, and the inside negative membrane potential. The charge reverses at that point on the neuron; it is now more positive on the inside of the cell and more negative outside of the cell. Sodium ions diffusing into the cell causes depolarization of the cell. Nerve impulses travel down the neuron and the change in charge opens the next sodium gates down the line. Sodium ions continue to diffuse into the…show more content…
First there is diffusion; the concentration gradient causes the ions to move from areas of high concentration to areas of low concentration. That is why sodium moves into the cell. Then there is electrostatic pressure, which has an electrical gradient that makes opposite charges attract and like charges repel. Both of these ion movements happen at the same time Potassium diffuses out of the cell because there is more potassium on the inside, so it wants to leave the cell because there is less potassium there. Sodium is a positive ion, so it wants to go inside the cell because it is attracted to the negative

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