The typical state of a neuron is the but when electrical signals stimulate it to its threshold, the is immediately observed. resting potential; action potential action potential; refractory period action potential; resting potential resting potential; refractory period

The answers, respectively, are:
resting potential; action potential.

Cell division is important to single celled organisms because it allows the cells to reproduce. through cell division, cells make exact copies of themselves. when single celled organisms go through cell division, they make exact copies of themselves which is how they reproduce.