Health Blog

Saturday 13 April 2013

How the eyes work


The eye is a very complex organ that allows us to record and keep an eye on things in the world around us. By using the eyes we see the shapes, colors, movements, contrasts and sizes.

The eye is spherical with a diameter of approximately 25 mm. It consists of three tissue layers on the outside of each other. The middle part of the eye's vitreous humor, a transparent jelly-like mass that keeps the eye stretched like a ball.

When light hits the eye, will be the first broken of the cornea (corneal). The cornea is the transparent layer that covers the front of the vessel and shall ensure that the light coming in through the undisturbed eye. Corneal main task is to protect the eye against scrapes and touch. If something comes in contact with the cornea (corneal epithelium, which specifically is corneal outer cell layer), the intestinal epithelium reacts immediately and triggers a reflex that closes the eye.

When the light passes through the eye, changing Rainbow cornea (iris) size. Rainbow corneal function is to regulate the amount of light that enters the eye and strikes the retina. By bright light extends Rainbow film itself, whereby the pupil (the light-emitting surface in the eye's iris) becomes smaller. Corresponding pulls itself together in low light Rainbow cornea and pupil expands.

The light that penetrates through the pupil, passes on to the lens. The lens changes shape and makes that the eye can focus on different distances.

The eye's innermost layer is the retina (retina). The retina is the screen, in which the things we see are displayed. The retina is used to send the information and impressions we get from the outside world, on to the brain that processes these so that we can understand and act upon them.

The eye's outer

The outside of the eye sitting six muscles that are used to respectively, turning the eye up or down, in or out, as well as to rotate the eye. The eyelids makes sure to keep the cornea moist by allocating the tear fluid and at the same time clean the cornea for dirt, so that any impurities does not bother the eye.

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