Nerves can be very long, sometimes as much as a metre.
When reacting to stimuli, impulses can travel through the nervous system in various ways.
- In a conscious reaction, impulses first go from your senses to your brain.
- In a reflex,a fixed, fast and involuntary reaction to a certain stimulus In a reflex. The impulses do not go through your brain
The spinal cord and the brain have interneurons. These are nerve cells that conduct impulses within the central nervous system, from one nerve cell to another.