Long answer type question:
Explain the mechanism of reflex action with the help of an example.
Reflex action is a form of animal behaviour in which the stimulation of a sensory organ (receptor) results in the activity of some organ without the intervention of will. For a reflex action, five things are normally
essential -
(i) receptor
(ii) sensory nerve fibres
(iii) a part of the central nervous system
(iv)motor nerve fibres
(v)effector organ such as muscles and glands.
The sensory nerve fibres bring sensory impulses from the receptor organ to the central nervous system and the motor nerve fibres relay the motor impulses from the central nervous system to the effector organs. hence completing a reflex action.