BIOC19H3 Lecture 4: Notes
Document Summary
Lecture 4: light comes into eye and passes through transparent layer = cornea, then it goes to little hole area: pupil. Pupil is formed by iris (muscular structure that gives color): lens held in place behind iris by zonal ligaments which are attached to 2 poles of lens. Zonal ligaments are attached to ciliary body- composed of involuntary muscle cells. When ciliary body contracts, it pulls on zonal ligaments and changes the lens" shape: behind lens, there is large volume of eye filled with gelatinous material = vitreous humor, around edge of vitreous humor, is retina. Light comes through cornea, pupil and is focused on retinal cells in back of eye. That light hitting retinal layer affects photoreceptors which sends signals to optic nerve, and to projection areas in brain, giving visual sensation of an image: around retinal layer and encasing the whole eyeball, there are 2 coating layers.
