If there is a problem with the muscles of the pupil then it will not regulate light into the eye correctly.
They die.
it gets bigger
Nothing. AFTER the light is detected and calibrated, the pupil may change size.
If the pupil of the eye did not work, than your eye could not regulate light entering it.
Please, note that you can not touch the pupil. It is well inside the eye, after the anterior chamber. What you think pupil is actually 'Cornea'. It is transperant. It is very sensitive as it is has rich supply of sensory nerve fibres.
With high intensity light your pupil constricts. This happens to protect your retina from damage by light of high intensity.
the pupil become not in his self
if you touch a snake nothing happens
well,in the day it is smaller,and,in the night,it is bigger
The muscles of the eye relax, causing the pupil to fully expand.
When the eye is stimulated by bright light, the circular muscle of the iris contracts, decreasing the size of the pupil.