2007-10-22 11:43:36 · 5 answers · asked by Anonymous in Science & Mathematics ➔ Astronomy & Space
the iris
2007-10-22 11:46:27 · answer #1 · answered by Anonymous · 2⤊ 0⤋
Structure Of The Pupil
2016-12-16 16:18:24 · answer #2 · answered by ? 4 · 0⤊ 0⤋
The pupil is found inside the eye just before the lense and the cornea.Around the pupil are two muscles namelly radial and circular muscles.The pupil is affected by light intensity either enlarging or shrinking.When you enter a dark room the pupil tries to allow as much light as possible to enter the eye to the retina so you can see.The cicular muscles relax while the radia; muscles contracts this allows the pupil to enlarge in size.When you enter a bright room the muscles try to reduce the amount of light entering the eye to prevent the retina from damaging.So the circular muscles cotract and the radial muscles relax.This causes the pupil to shrink in size .This a called an involuntary action because it done without you thinking about it.
2016-05-24 20:13:39 · answer #3 · answered by ? 3 · 0⤊ 0⤋
When bright light is shone on the eye, it will automatically constrict - this is the pupillary reflex. The oculomotor nerve ends on the circular iris sphincter muscle. When this muscle contracts, it reduces the size of the pupil. When this muscle relaxes, the pupil expands.
2007-10-22 11:47:31 · answer #4 · answered by Anonymous · 0⤊ 1⤋
The circular and radial muscles which form the iris.
2007-10-22 11:47:08 · answer #5 · answered by Romenl 1 · 0⤊ 0⤋
Ceiling height in the homes and schools...
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internal volume of hamburger boxes...
internal volume of french fry container evelopes...
2007-10-23 15:59:13 · answer #6 · answered by zahbudar 6 · 1⤊ 1⤋
There are pupillary muscles, actually two of them ( :circular muscles and radial muscles) that control this function.
2007-10-22 11:51:10 · answer #7 · answered by originalsmartie 4 · 0⤊ 0⤋
The BRAIN... controls all..
2007-10-22 11:47:54 · answer #8 · answered by marco polo 2 · 0⤊ 2⤋