Q20 of 54 Page 49

Blinking when a beam of light is suddenly focussed on the eyes and sudden withdrawal of hand upon touching a hot body are some of the examples of reflex actions. Which part of the central nervous system acts as the centre these actions?

Reflex action is a process in which immediately message is sent to brain and an immediate response is also given.

It can happen only when neurons can transmit signals to the brain and from the brain. Also, it is an involuntary action which does not involve thinking process in which time is consumed. So, brain is not the centre for reflex actions.


In spinal cord we have mixed neurons and therefore an immediate action can take place. So, this process can take place only there.


Therefore, spinal cord is the correct answer. All other options do not play any role in the reflex actions.


Following picture explains the same:


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