Question

taking heartbeat as an example justify the antagonistic action of the sympathetic and the parasympathetic nerve

Answer 1

Pacemaker present in the heart produce action potential that results in the contraction of cardiac muscles and hence pumping of blood. 

Frequency of action potential produced by the pacemaker is under the control of sympathetic and parasympathetic nervous system.

Sympathetic nervous system increase the frequency of action potential thus increasing the heart rate whereas antagonistically parasympathetic nervous system decrease the frequency of action potential thus lowering the heart beat. Both of them act antagonistically to control the heart beat...........

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Answer 2

Answer:

Sympathetic system increases contraction and rhythm and parasympathetic system decreases contraction and rhythm with respect to heart beat