2.85- Reflex arc

Describe the structure and functioning of a simple reflex arc illustrated by the withdrawalof a finger from a hot object

• The hot object is the stimuli
• The receptor is the sensor in our finger and this detects the hot object
• The electrical impulse travels along the sensory nerve to the CNS
• It is then passed on to the relay nerve which in turn passes it onto the motor nerve
• The impulse is then carried to the finger to which the response is to move the finger away
• The brain also receives some of the impulse but not all of it
• This makes the process faster and prevents more damage