The eye is the organ of sight.
It is a small paired organ, each eye being a leathery sphere of about 2.5cm diameter.
The function of the eye is to target an object of interest, gather and focus light from the object and transmit a clear image to the light-sensitive tissues which line the back of the eye where the image is received and initially processed.
The image is then transmitted by electrical impulses along the optic nerve, a nerve which connects the back of the eye to the brain. The optic nerves join together in the brain in such a way that images from both eyes are merged to give binocular vision.
The part of the brain which receives these visual messages is called the visual cortex and lies at the very back of the brain.
From the visual cortex, connections reach out to many other parts of the brain. The experience of sight is the result of very high-level processing of the basic electrical impulses which are the raw input from the eyes themselves.
Cool. Did you know that the human eye is adult size at birth? Humans have to look directly at something to draw focus? Whereas horses can see out of the corner of their eyes with perfect focus :)
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