The cornea is the transparent part that covers the front portion of the eye. It covers the pupil ( the opening in the center of the eye) and the iris ( the coloured part of the eye).

The main function of the cornea is to refract, bend and focus most of the light entering the eye. One the interesting facts about the cornea is that it is the only part in the human body that does not have blood supply. That's because if it had blood supply then the blood vessels ( arteries and veins) passing across it would interfere with the vision. The cornea received its oxygen supply from the surrounding atmosphere and it's wastes are cleared through tears. Although it does not have a blood supply, cornea is the fastest healing part of the human body and most of it abrasions heal within 24 hours.

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