This is a 2 part question. I shall ask B after A is answered.
A) Is it true that the only part of the eye that we actually see out of is the pupil? And that the pupil expands when it is dark to let more light in, and contracts when it is bright to let less light in?
If i'm understanding you're question correctly, yes. The only part of the eye that light can get through is the pupil. It is basically just the opening in the middle of the iris, and is made smaller to let less light in and larger to let more in.
Mat - it almost seems as if you are asking a question within a question. Methos is right, the opening in the center of the iris (the pupil) is what admits light to the lens....BUT, it is the LENS that brings the light rays to focus forming images on the retina...stimulating the optic nerve...transmitting images to the brain...and thus allowing us to "see"
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OK, thanks both of you. Now the second part of the question.
B) Since the pupil expands at night, does this give us a larger range of vision? Same with the pupil shrinking in bright sunlight, does our range of vision shrink?
