In a resting state, sodium (na+) is at a higher concentration outside the cell and potassium (k+) is more concentrated inside the cell. during an action potential, the sodium levels inside the cell

In synapsis, when the neurotransmitter joins its receptor, ion channels open in the postsynaptic cell allowing Na and K ions to interchange. During an action potential, the sodium levels _INCREASE_ inside the cell.

During synapsis, the neurotransmitter is released from the presynaptic membrane. It moves through the intercellular space toward the postsynaptic membrane.

Once there, the molecule binds to its receptors on the postsynaptic membrane, causing ion channels to open.

When the joining has occurred, the receptor acquires a channel shape allowing the ion transference that will make possible the modification of the action potential.

Ions traffic consists of the pass of positively charged sodium and calcium ions to the interior of the cell and potassium to the exterior. Quantitatively, the interchange Na-K is the most significant.

K+ follows a concentration gradient, while Na+ follows an electrochemical gradient. The interchange results in an increase of positive charges in the interior of the cell.

The difference in charges caused by these ions' transport depolarizes the postsynaptic cell.

So, basically, during an action potential, the sodium levels _INCREASE_ inside the cell.

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During an action potential, sodium levels increase within the cell

Explanation:

An action potential is a biological process that occurs within the cell and triggers an inversion in the variation of the plasma membrane potential. When the action potential occurs, the membrane allows substances to enter and exit the cell according to their needs.

Based on this, we can say that if at rest, sodium (na +) is at a higher concentration outside the cell, during the action potential the cell will be allowed to absorb this sodium by increasing its concentration within the cell. Likewise, if in the resting state the potassium levels inside the cell are higher than outside the cell, during the action potential, these the cell will "expel" potash, allowing its concentration inside the cell to decrease.

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