Question
What are reflex actions? Give two examples. Explain a reflex arc.

Answer


Reflex action: A reflex action, is an involuntary and nearly instantaneous movement in response to a stimulus.
For example:
  1. Moving away your hand upon touching a hot object.
  2. Closing your eyes on sudden exposure to bright light.
Reflecx arc: Reflex arc is a simple nervous pathway and consists of receptors, sensory neurons, interneurons, motor neurons and muscles. The sensory neurons transmit the sensory information from sensory receptors to spinal cord or brain. The interneurons integrate the incoming information and signal is relayed to motor neurons. The motor pathway transmits the signal from motor neurons to the effector organs (usually muscles and glands).

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