1. video http://www.youtube.com/watch?v=gvozcv8pS 3c http://www.youtube.com/watch?v=gvozcv8pS 3c

2. How you see Light waves enter eye Light waves bend so as to focus on retina (refraction)

3. Refraction Cornea Aqueous humor Lens – change shape and refractive ability – Elastic structure – Fatter (bends at a sharper angle) or thinner – Held in place by suspensory ligaments attached to ciliary muscles

4. lens Over time, lens loses some of its ability to change shape – can’t accommodate to close objects

5. Role of the iris Pupil: regulating amount of light Acute vision

6. Retina Photoreceptors concentrated – Rods: concentrated in periphery, black and white, movement, respond to dim light – night vision. Vitamin A – Cones: color, heavily concentrated around central portion of retina, colored and sharp images,

7. translation Photoreceptors excited  nerve impulse  optic nerve  occipital lobe  “vision”

8. Focus: convergence Both eyes work together to form a single image “Lazy eye” – eyes not focusing on the same thing – occipital lobe can’t process both signals, suppresses images from the lazy eye, can lead to blindness

9. What three things help eyes focus on one object? Accommodation Pupillary constriction convergence

10. http://www.sciencechannel.com/tv- shows/cheat-sheet/videos/how-do-our-eyes- work.htm http://www.sciencechannel.com/tv- shows/cheat-sheet/videos/how-do-our-eyes- work.htm