One function of parasympathetic nervous system is

Options

A. contraction of hair muscles
B. stimulation of sweat glands
C. acceleration of heartbeat
D. constriction of pupil

Answer

D

Explanation

Parasympathetic nervous system involves conservation of energy and brings about relaxation, comfort, pleasure etc, at the time of rest. Another function of this system is that during emergency or stress while SNS dilates pupil for more light, PNS constricts the pupil for more light, PNS constricts the pupil for its normal condition. Whereas, sympathetic nervous system involves expenditure of energy and increases the defence system of body against adverse conditions, so, it operates during stress, pain fear and anger.