As far as I know, when the light is too intense, the eye pupil contracts to reduce the ammount of light that enters the eye.
So, when this happens, does the eye iris become WIDER?
2007-07-19 07:18:11 · 3 answers · asked by Anonymous in Science & Mathematics ➔ Biology
first off the pupil can't contract because it's a hole. the iris is what contracts. So when the pupils become smaller the iris appears larger.
2007-07-19 07:22:43 · answer #1 · answered by Carolyn R 2 · 2⤊ 0⤋
The pupil is not a physical structure. It is simply the hole in the iris. Pupil contraction is merely the iris's inner diameter growing smaller. The iris does have more surface area in this state, but it is not wider.
2007-07-19 14:22:07 · answer #2 · answered by lithiumdeuteride 7 · 0⤊ 0⤋
The pupil itself does not contract, as it is literally just a hole (covered by the cornea). The iris does all the "contracting".
When it is light, the circulatory muscles (of the iris) contract and the radial muscles (pf the iris) relax.
When it is dark, the circulatory muscles (of the iris) relax and the radial muscles (of the iris) contract.
2007-07-19 14:29:08 · answer #3 · answered by ♪Melody♫ 5 · 0⤊ 0⤋