CSD exam 2 (visual system)

Function of cornea

mediates refraction

Function of iris

adjust amount of light entering eye

Function of pupil

hole where light enters the eye

Function of lens

accommodation of image

Function of retina

converts lights into electrical signals; contains 3 layers:

• photoreceptor - signal colors

• bipolar cells - transmits signals from photoreceptors → ganglion cells

• retinal ganglion cells - transmits retinal information → midbrain

Function of rods

sensitive to light and movement

• mostly in PERIPHERAL regions of retina

Function of cones

mediate color vision

• mostly in CENTRAL region of retina (where visual acuity is highest)

photon

particle of light (electromagnetic energy)

What process converts a photon into a neural impulse?

phototransduction

optic nerve

optic chaism

optic tract

optic radiation