‘Reflex’ is a word we use very commonly when we talk about some sudden action in response to something in the environment.
Reflex action is the extremely quick, automatic, sudden action in response to something in the environment.
i) Immediately pulling back of fingers after touching a hot plate.
ii) Closing of eyes when flashed with high intensity light.
iii) Salivation when hungry.
Reflex arc is the pathway of nerve involved in reflex action. Reflex arc involves-
Receptors- receive the message from external environment.
Sensory neuron- carries the message from the receptor to the central nervous system.
Central nervous system- processes the message and sends impulses to the concerned part of the body in the form of response.
Motor neuron- carries the message from the central nervous system to the effector.
Effector- responses against the stimulus.