nervous system

• the nervous system enables animals to react to their surroundings and coordinate their behaviour
• the nervous system is made of cells called neurones.
• There are 3 main type of neurones: sensory neurones, motor neurones, relay neurones
• sensory neurones: transmits impulses from receptors to co-ordination centre
• motor neurone: transmits impulses from co-ordination centres to effectors
• relay neurone: relay impulses in the spinal cord from sensory neurones to motor neurones