structure and functions of the eye

Front

Sclera

Back

Tough, outer, white layer; helps maintain shape of the eye

Front

Choroid

Back

Vascular middle layer; nourishes outer layers of the retina through the blood vessels

Front

Retina

Back

Innermost layer of the eye; Light rays reflect here to form an image; contains rods and cones

Front

Rods

Back

Sensitive to dim light

Front

Cones

Back

Sensitive to bright light and color

Front

Optic disc

Back

On retina, known as blind spot, nerve fibers form optic nerve here

Front

Cornea

Back

Circular clear area in front center of the sclera; “window of the eye”; is transparent and permits the passage of light rays

Front

Iris

Back

Colored, muscular layer that surrounds the pupil. Intrinsic muscles within the iris control the size of the pupil and amount of light entering the eye

Front

Lens

Back

Crystalline structure located behind iris and pupil; separates anterior and posterior chambers; focuses images on the retina

Front

Aqueous Humor

Back

Clear fluid filling the space in the front of the eye between the lens and cornea