It is the sensory organ, a component of the sensory nervous system.
It reacts with the visible light and permits one to utilize visual information for different purposes like keeping the balance, seeing things, and maintaining circadian rhythm.
The eye is formed of three layers of coats that enclose different anatomical compositions.
The fibrous tunic is the outermost layer of the eye, which comprises the sclera and cornea that support the deeper structures and provide shape to the eye.
The vascular tunic is the middle layer, which comprises the ciliary body, choroid, iris, and pigmented epithelium.
The innermost layer is the retina which gets its oxygenation from the retinal vessels as well as from the blood vessels of the choroid.
The spaces of the eye are occupied anteriorly with the aqueous humor, that is, between the lens and cornea, and with the vitreous body behind the lens occupying the entire posterior cavity.