Definition of Retina
Retina: The retina is the nerve layer that lines the back
of the eye, senses light, and creates impulses that travel through
the optic nerve to the brain. There is a small area, called the
macula, in the retina that contains special light-sensitive
cells. The macula allows us to see fine details clearly.
The eye has a number of other components. These include the
cornea, iris, pupil, lens, optic nerve and vitreous.
The cornea is the clear front window of the eye that
transmits and focuses light into the eye.
The iris is the colored part of the eye that helps
regulate the amount of light that enters the eye.
The pupil is the dark aperture in the iris that
determines how much light is let into the eye.
The lens is the transparent structure inside the eye that
focuses light rays onto the retina.
The optic nerve is the nerve that connects the eye to the
brain and carries the impulses formed by the retina to the visual
cortex of the brain.
The vitreous humor is a clear, jelly-like substance that
fills the middle of the eye.
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