NURSING ANM AND GNM

Detailed explanation-1: -The sodium current during the upstroke reaches a maximum shortly before the peak of the action potential. At exactly the time of the peak, there is a dip in the sodium current reflecting the decreased driving force on sodium ions.

Detailed explanation-2: -Action potentials are caused when different ions cross the neuron membrane. A stimulus first causes sodium channels to open. Because there are many more sodium ions on the outside, and the inside of the neuron is negative relative to the outside, sodium ions rush into the neuron.

Detailed explanation-3: -The falling phase of the action potential is caused by the inactivation of the sodium channels and the opening of the potassium channels. After approximately 1 msec, the sodium channels inactivate. The channel becomes blocked, preventing ion flow. At the same time, the voltage-gated potassium channels open.