Anatomy of the Eye

Layers of the Eye

• Sclera is the white outer layer that provides firmness to the eye, composed of connective tissues.
• Choroid is the middle layer containing a large number of blood vessels.
• Retina is the inner layer with photoreceptors.

Parts of the Eye

• Cornea is the transparent anterior part of the sclera that refracts light rays to focus on the retina.
• Conjunctiva is the layer that covers and protects the front part of the sclera, except the cornea.
• Iris is the part of the choroid seen behind the cornea, and its dark color is due to the presence of the pigment melanin.
• Pupil is the aperture at the center of the iris, and its size increases and decreases depending on the intensity of light.
• Lens is an elastic, transparent, and convex lens connected to ciliary muscles by thread-like ligaments.
• Ciliary muscles are circular muscles around the lens, and their contraction and relaxation alter the curvature of the lens.
• Yellow spot is the part of the retina with plenty of photoreceptors, resulting in maximum visual clarity.
• Blind spot is the part of the retina where the optic nerve begins, and there are no photoreceptors, resulting in no vision.
• Optic nerve transmits impulses from photoreceptors to the visual center in the brain.