LC Biology eye

The white part of the eye. (opaque and tough)

function: shape and protection

The transparent part of the sclera at the front of the eye.

Let's light in and bends it towards the retina

Transparent membrane protecting the cornea

contains the blood capillaries to nourish the eye and melanin (black pigment) to absorb light (no internal reflection of light)

the innermost layer containing the light receptors (rods and cones)

contain rhodopsin (vitamin A required to form it)

detect black and white

work in dim light

found all over retina

Have 3 pigments that detect blue, red and green

detect color

found mostly in the fovea

work in bright light

the area where the optic nerve leaves the eyeball

contains no visual receptors

opposite the centre of the pupil

contains cones only. Regions of sharpest vision, most images are formed here

Carries impulses from the retina to the brain.

coloured part of the eye. Controls size of pupil and amount of light entering the eye (reflex action).

Its circular muscle contract to narrow the pupil in bright light to reduce the amount of light and its radical muscles contact to widen the pupil in dim light enters the eye

opening in the iris through which light enters.

biconvex, transparent and elastic, changes shape to focus light on to the retina. Contains a clear protein which can become cloudy (cataracts).

changes shape of the lens

Attaches the ciliary body to the lens.

A watery liquid between cornea and lens, made in ciliary body-maintains eye shape; nourishes cornea and lens (these don't have their own blood supply) and helps to refract light.

A jelly-like substance between lens retina, gives shape to the eye

changing the shape of the lens to focus near and distant objects