Eye Structure

Front 1

Cornea

Back 1

• The most anterior portion of the eye that budges outward
• Does the majority of the refracting of light
• Stratified Squamous Epithelium cells

Front 2

Iris

Back 2

• Regulates the amount of light into the eye

Front 3

Crystalline Lens

Back 3

• Does very fine refracting of light
• Shape is controlled by suspensory ligaments
• Rounder helps to focus light from many angles
• Flatter helps to focus straighter beams of light

Front 4

Suspensory Ligament Function

Back 4

• Muscles contract to relax the ligament, making the lens rounder
• Muscles relax to increase tension on ligament, making the lens flatter

Front 5

Choriod

Back 5

• Highly vascularized portion of the "outside" eye
• Gives nutrients to the retina via diffusion
• Increased pressure causes decreased blood flow, causing blindness

Front 6

Retina parts

Back 6

• Inside the choroid
• Rods: very sensitive to light, but only see in black and white
• Cones: red, blue, green sensitive, but are less sensitive than rods
• Very dense amounts of cones increase resolution

Front 7

Myopia

Back 7

• Nearsightedness
• Eyeball is too long (Focus point is before the retina)
• Need "flattened" (biconcave) lenses to lengthen the FP

Front 8

Hypermytropia

Back 8

• Farsightedness
• Eyeball is too short (FP is behind the retina)
• Convex (rounder) lenses decrease the FP length

Front 9

Astigmatism

Back 9

• Cornea is not perfectly round
• Try to correct the shape

Front 10

Canals of Schemm

Back 10

• At the border between the sclera and the iris
• brings the aqueous fluid of the eye back into the venous system
• Can become partially or fully blocked (glaucoma)

Front 11

Schlera

Back 11

• The "white" of the eye
• made of dense fibrous tissue

Front 12

Close vs Far light angles

Back 12

• Close: has more angles of light, so needs to be focused more
• Far: has more straight angles of light, so does not need as much correcting

Front 13

Fovea Centralis

Back 13

• The part of the retina with the most cones
• Provides the clearest image
• Runs to the optic nerve

Front 14

Hyaloid canal

Back 14

• Runs from the optic nerve to the lens
• Remnants of an artery used during fetal development to provide nutrients to the lens