How do nerve impulses travel across an un-myelinated neurone?
nerve impulse is positive which causes nearby voltage-gated sodium channels to open which then sodium ions outside the neurone diffuse down the electrochemical gradient
the inside of the neurone becomes more positive which opens more voltage gated sodium channels
eventually the threshold will be met and an action impulse is generated and voltage gated sodium channels close and voltage-gated potassium channels open which cause potassium ions to leave the neurone which causes the inside of the neurone to become less positive
