Answer: Light passes through the pupil, or can also pass by the front of the eye (cornea). The amount of light that gets controlled from is the colored part of the eye (iris). The light later on, hits the lens. The light rays get focused onto the retina. The cells inside the retina can convert the light through electrochemical impulses. Then are transferred to the optic nerve (located at the back of each eye that connects directly to your brain), then to the brain.
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