Eyelid
structure that blocks external debris and helps lubricate eye
Blink reflex
semi-autonomous way to block foreign bodies from entering the eye;
assisted by the eyelashes
Tear Duct
small openings that drain tears into the nasal cavity
Lacrimal gland
release tears onto surface of eye
Sclera
Supports and protects the eye; makes up most of outer layer and optic nerve
"white of eye
Sclera (diagram)
eyelashes
hairs that help block debris from entering eye
Cornea
Dome shaped and clear, this structure covers the pupil, iris, and
anterior chamber
protects the iris and pupil
provides much of the eye's focusing power
Cornea (diagram)
structure labelled A
Meibomian Glands
found at rim of eyelids ; produce oily substance that helps prevent
evaporation of tear film.
Conjuctiva
Lines the inside of the upper and lower eyelids
Continuous with the cornea
Lies on top of sclera
Pupil
small hole that controls how much light enters your eye
Iris
Controls the size of the pupil
Lens
Focuses the light that enters your eye
Lens Diagram
Structure labelled F
Suspensory ligaments
Connect the ciliary muscles to the crystalline lens
Anterior Chamber
Acts as a channel for the aqueous humor to travel through
located between the iris and the inner layer of the cornea
Diagram of anterior chamber
Structure labelled F
Aqueous humor
contains electrolytes, ascorbic acid, and amino acids
provides nutrients and oxygen
helps maintain pressure and keep anterior and posterior chamber inflated
ciliary body
controls the shape of the crystalline lens and produces the aqueous humor
circular in shape, it separates the posterior chamber from the vitreous
Ciliary body diagram
structure labelled H
Vitreous
Clear gel that exerts pressure on the inside of the eye
function of this pressure is to keep retinal layers tightly pressed together
Vitreous diagram
Structure labelled E
Macula
highly sensitive circular area that is responsible for providing
detail and color to your vision in bright light conditions
part of retina that produces central vision
structure of eye that is used to detect detail and reading/close work
Fovea
Part of the retina that provides sharp and accurate color vision
small dip in the retina at the center of the macula
Retina
Layer of photosensitive cells that process and convert light energy
into electrical signals. The signals are then transmitted to brain
through optic nerve and interpreted as images.
Optic disc
optic nerve head; beginning and innermost section of optic nerve in retina
has no photoreceptors
does not react to light
optic nerve
transmits impulses received from retina to the visual cortex in the
brain, forming an image in our minds
Rods
Greater sensitivity to dim light
helps you see in dark
not sensitive to color
Cones
found mainly in fovea
responsible for color vision in bright light
helps you see detail and color in day
Diagram of iris
structure labelled E
Diagram of pupil
Structure labelled C
Diagram of vitreous humor
Structure labelled K
Diagram of Retina
Structure labelled C
Diagram of Optic nerve
Structure labelled D