Sense Organs (Cambridge (CIE) IGCSE Biology): Revision Note

Sense Organs as Receptors

• Receptors are groups of specialised cells

• They detect a change in the environment and stimulate electrical impulses in response

• Sense organs contain groups of receptors that respond to specific stimuli

• Once the receptor cell in the sense organ has been stimulated, it generates an electrical impulse

• This is passed on to a sensory neurone which carries the impulse to the central nervous system

• Here a response will be decided on and the impulse will be passed to a motor neurone (via a relay neurone)

• The motor neurone carries the impulse to the effector (muscle or gland)

• The effector carries out the response