Vision & Light Path Flashcards
Conjunctiva
Thin clear layer that covers the eye
Conjunctiva conditions
Conjunctivitis - inflammation (pink eye)
-causes: bacterial/viral, particle in eye
Cornea/sclera
(Same layer) outer covering of the eye
- cornea: transparent (no blood vessels)
- sclera: white w/ blood vessels
Cornea/ sclera: astigmatism
Imperfection in cornea or lens
Cornea gets nutrients from…
Aqueous Humor
Aqueous Humor jobs
- provides oxygen and nutrients to cornea
- maintains pressure in eye
To much aqueous humor causes
To much pressure. This is called glaucoma.
Aqueous humor drains from…
The canal of schlemiel
Pupil/ iris
Pupil- opening
Iris- colored and controls pupil size with muscles
Lens
Focuses the image, bends light to focus
Lens is similar to a tree ring because
Adds new layers all the time, the older you get the less movement your lens has
Lens: Cataracts
Layers on lens are no longer transparent and it blocks light
Vitreous Humor
Jelly-like substance to support the eye (you don’t produce more)
Retina
Light doesn’t actually pass through
Retina is only attached to…
The vitreous humor
Retina
Detects the light with light receptors
Light receptors
- rods (b and w)
- cones (color)
No light receptors in…
The blind spot
Color vision- color blinding
Focuses on the X chromosome (effects cones)
- red-green (most typical)
- blue-yellow
Optical nerve
Electrical impulse
Brain
Last part of the light travel path
20/20 vision
The bottom 20 represents where/how far someone would be for the chart
Binocular Vision
Provides depth perception
Protective structures
Cheek bones, eyebrows, eyelid, lashes, tears
Path of light through eye
- Conjunctiva
- Cornea/sclera
- Aqueous Humor
- Pupil/iris
- Lens
- Vitreous Humor
- Retina
- Optic Nerve
- Brains
