The word “action potential” is a saying used by scientists to express the action of neurons receiving enough input from all the dendrites to overcome electrical threshold. Though many psychologists study the topic of action potentials, it is the chemistry that actually creates this process. Before action potential happens, it is considered in resting potential. This is where different concentrations of ions are inside and outside of the cell. Inside the cell’s axon membrane consists of larger negatively charged proteins and K+. Outside consists of Na+ and Cl-. In order for the neuron to react, it needs to reach threshold, which is at -65mV (some say around -80mV). Once threshold is met, there will be an action potential in the neuron created by the potassium-sodium pump. This process opens the gates of the axon allowing the positively charged sodium ions to flow in the axon membrane as it attracted to the negatively charged cell. This negatively charged cell becomes more and more positive because the sodium moves in; creating an excited state of +40mV. The potassium pumps initially stay closed because the flow of charge is only going in one direction, but as the membrane fills up, the potassium gates open and flow of positive charges go out of the cell therefore creating its negative resting place once again.
I think this topic is really interesting because it defines how and why we can move our body or process information. If one day we woke up unable to move our legs out of bed; that could be because our resting potential was not meeting threshold to create an action potential. The actual chemistry of this reaction, how we have certain elements in our body that provide such vital jobs for us, is fascinating. Learning about how potassium and sodium interact with each other on a molecular level is really interesting when it has to do with our own body’s movement.
Submitted by Dana Smith
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