1. SPECIAL SENSES

2. THE EYE Properties of light External eye –Palpebra –Eyeball –Protection provided by – –Meibomian glands (eyelashes) –Conjunctiva –Lacrimal glands

6. EYE MOVEMENTS 3 pairs of muscles Medial rectus Lateral rectus Superior rectus Inferior rectus Superior oblique Inferior oblique

7. Internal Eye 3 tissue layers + 2 fluid filled cavities 1)Outer, fibrous tunic 1)Sclera “Canal of Schlemm” 2)Cornea 2)Middle vascular tunic 1)Choroid 2)Ciliary body (ciliary muscles + ciliary process) 3)Lens 4)Iris

8. 3)Inner retina or nervous tunic 1)Photoreceptor cells 1)Rods (rhodopsin) 2)Cones (cyanolabe, erythrolabe, chlorolabe) 2)Fovea centralis (cones only) 3)Optic disk 4)Macula lutea

9. CAVITIES 1.Anterior 1.Aqueous humor 1.Ciliary process 2.Canal of Schlemm 2.Posterior 1.Vitreous humor

10. LENS Changes shape and focuses light onto retina Accommodation

11. DISORDERS Myopia

12. Hypermetropia Astigmatism

13. Cataract Glaucoma Presbyopia Color blindness http://www.wisc- online.com/objects/ViewObject.aspx? ID=AP14304