Question

What is a reflex action? Describe the steps involves in reflex action.

Answer 1

Relex action: It is a spontaneous, voluntary and automatic response to a stimulus to protect us from harmful situations. Eg: Sudden jerky withdrawal of hand or leg when pricked by a pin.

The neural pathway that controls the reflexes occurs through the reflex arc. Nerves from all over the body meet in a bundle in the spinal

cord on their way to the brain. Reflex arcs are formed in this spinal cord

itself, although the information input also goes on to reach the brain.

Stimulus --> receptor organ --> sensory nerve --> spinal cord --> effector organ --> responce.

The receptor here is the sense organ that senses danger. The sensory neurons pick up signals from the sensory organ and send them through other neurons which are interconnected. It is then received by the relay neuron which is present in the spinal cord. Immediately, the spinal cord sends back signals to the muscle through the motor neuron. The muscles attached to the sense organ move the organ away from danger. In reflex actions, the signals do not travel up to the brain.