Anatomy

Description and Function

Conjunctiva-
A thin layer of epithelial cells, covering three layers of fibrous tissue, which keeps the outer surface moist.
Sclera-
The white of the eye on the outside which covers the entire eye except the front. Supports and protects the eye while serving as an attachment foreye muscles as well as aids in focusing.
Cornea-
Transparent part of the eye located at the front. Allows light to enter the eye.
Choroid-
The second layer, situated between the Sclera and retina. Provides support and protection for the eye.
Retina-
The inner most layer of the eye containing photoreceptor cells. Converts light stimuli into an electrochemical message that is sent to the brain for interpretations.
Fovea-
Central area of the Retina where images are focused most sharply.
Iris-
A highly pigmented doughnut shaped structure, extending from the Choroid, surrounding a small opening, the pupil. Muscles in Isis contract to change the diameter of the pupil thus altering the amount of light entering the eye.
Lens-
A transparent biconvex disc made of protein. It focuses the light into the retina, by chancing its shape.
Ciliary Body-
An extension of the Cornea and Sclera which attaches to both the Iris and Lens, holding both in place yet allowing flexibility. Also divides the eye into the anterior and posterior cavity.
Aqueous Humour & Vitreous Humour-
Within the anterior cavity a fluid is continuously being produced called Aqueous humour. This fluid fills the cavity. Within the posterior cavity a jelly-like substance, Vitreous humour, fills the eyeball and maintains the volume of the eye.
Optic Nerve-
A group of nerve fibres which travels from the retina to the brain. Transfers the visual sign generated at the retina to the brain for processing.