Three Layers of the Eye
Three Fluid Filled Chambers of the Eye
The space between the cornea and lens is called the anterior chamber. It is filled with aqueous humor, a fluid which provides nourishment for the cornea and lens, and keeps the eyeball round and firm.
The Three Fluid Chambers of Eye:
- Anterior Chamber - Between the cornea and iris, containing aqueous humor
- Posterior Chamber - Between the iris and the lens, containing aqueous humor
- Vitreous Chamber - Between the lens and the retina, containing the more viscous vitreous humor
The choroid layer is between the sclera and the retina. This layer of the eye is rich in blood vessels that supply the eye's tissue with nutrients and oxygen.
The ciliary muscles contract and release, and allowing the lens to bulge at the center to accomodate focusing.
The cornea is the transparent "window" of the eye. The cornea focuses light rays through the pupil, and onto the lens. From there, the light rays form a sharp image on the retina.
The iris, a colored circular muscle, controls the size of the pupil, regulating the amount of light that enters the eye.
The Three Layers of the Eye:
- External Layer - Formed by the sclera and cornea
- Intermediate Layer - Consists of two parts:
- Anterior - Containing the iris and the ciliary body
- Posterior - Containing the choroid
- Internal Layer - This is the sensory layer, containing the retina
The lens is an elastic crystalline structure directly behind the pupil. The lens makes fine adjustments to the focused light rays, before they reach the retina.
The optic disc, also known as the optic nerve head, is a circular area where the optic nerve connects to the retina.
The optic nerve is a collection of millions of nerve fibers at the back of the eye.
The pupil is the dark-looking aperture at the center of the eye. It regulates the amount of light that passes through the eye, by dilating or contracting. The pupil appears dark because of the absorbing pigments in the retina.
The retina is a thin nerve layer lining the back of the eye. Along the retina, the rods and cones sense light, and create impulses, that travel to the brain and are interpreted as images.
The sclera is the tough, white, outer layer of the eyeball. It is continuous with the cornea, forming the supporting wall which protects the eyeball.
The large cavity behind the lens, is filled with a transparent fluid called vitreous humor.
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