resting potentials

• • impulses carried along neurone as an electrical signal it is not a flow of electrons but a change across the cell membrane
  • this is due to movement of Na+ and K+ in myelinated neurones, this happens at the nodes of ranvier.
• • In a resting neurone, sodium-potassium pump pumps out 3 sodium ions for every 2 potassium ions it brings into the cell
  • potassium ions can diffuse out of the cell through some open channels in the cello membrane
• • Overall, the inside of the cell is more negative than the outside because it is easier for potassium to diffuse back out of the cell than sodium due to some of the potassium channels being open