"what is the basic condition when a neuron is described as polarized? " na+ is found outside of the neuron. there are large, protein anions inside the neuron. na+ is found outside of the neuron and k+ is found inside of the cell. there is a separation of positive and negative charges across a membrane.

The cell membrane separates the inside of a cell (all cells, not just neurons) from the outside, and all chemicals that get into and out of the cell must go thorough it. As in all cells, the cell membrane of a neuron is polarized. This means that there is an electrical difference across the cell membrane.