Question

q4.7. why does na⁺ enter the cell during the action potential? because the na⁺ channels are open and only let na⁺ move from outside to inside because the action potential pulls positive ions into the cell while na⁺ and k⁺ channels are open because na⁺ channels are open and allow na⁺ ions to move down the length of the axon to produce neurotransmitter at the axon terminal because na⁺ channels are open and there is a higher concentration of na⁺ outside of the neuron than inside

Explanation:

During an action potential, when sodium ($Na^+$) channels open, $Na^+$ enters the cell due to the concentration gradient. There is a higher concentration of $Na^+$ outside the neuron compared to inside, so $Na^+$ moves down this concentration gradient into the cell.

Answer:

Because $Na^+$ channels are open and there is a higher concentration of $Na^+$ outside of the neuron than inside