1. Neurons and Nerves Impulses
The structure of a motor neurone, sodium-potassium pumps and the resting potential.

2. Neuron Structure

3. Sodium-potassium pump
Uses ATP to move Na+ and K+ ions across the axon membrane
Sodium potassium pumps are found
along the membrane

4. Resting Potential

5. Summary The resting potential is caused by two processes:
Active transport of K+ ions into the neurone and Na+ ions out of the neurone.
Facilitated diffusion of K+ ions back out of the neurone.
The tissue fluid around the neurone then contains more positively charged ions than the cytoplasm inside.
A 'potential difference' forms across the membrane, called the "RESTING POTENTIAL"