Taking a Look at the Human Eye

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The human eye is an organ that reacts to light and has several purposes. As a conscious sense organ, the eye allows vision. Rods and cones in the retina allow light perception and vision including color differentiation and the conscious perception of depth. The human eye can distinguish 10 million colors. The eye is composed of three layers, enclosing three transparent structures .
The outer layer , called the fibrous tunic is comprised of the cornea and sclera . The middle layer , called the vascular tunic or uvea is the choroid , ciliary body and the iris. The innermost part of the eye is the retina , which gets its circulation from the vessels of the choroid and retinal vessels , which can be seen in an ophthalmoscope .
The blood vessels can be seen in the sclera , and a strong ring around the iris limbo . Within these coats are the aqueous humor , vitreous humor and the flexible lens . The aqueous humor is a clear fluid that is contained in two areas: the anterior chamber between the cornea and the iris and the posterior chamber between the iris and lens.
The lens is suspended in the ciliary body in the suspensory ligament , composed of transparent fibers . The vitreous is a clear gel that is larger than the aqueous humor is behind the lens , and the rest is enclosed by the sclera , zonule , and lens. They are connected by the pupil .
As the eyes of other mammals, the ganglion cells of the human eye is not sensitive image forming on the retina receive the light signals
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