Regarding the Assertion and Reason, choose the correct option:
Assertion [A] : Sympathetic and parasympathetic systems have opposing functions.
Reason [R] : The parasympathetic nervous system ‘prepares you’ for action, while the sympathetic system ‘calms you’ down after action.
Assertion [A] is true and reason [R] is false.
Sympathetic and parasympathetic nervous system are the two parts of the autonomic nervous system and have opposing functions. But it is the sympathetic system that readies the body for fight or flight response, while parasympathetic system helps return the body functions to rest levels. For eg. the sympathetic fibres increases the rate and intensity of heartbeat, constrict most blood vessels and raise the arterial blood pressure, thus preparing the body for action. The parasympathetic fibres however decrease the rate of heartbeat, dilate many blood vessels and lower the arterial blood pressure.Therefore, assertion is true but reason is false.