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Science 8 - Eye
Eye - Chapter 12
| Term | Definition |
|---|---|
| Sclera | Tough, white outer layer of the eyeball (6 muscles attach and move the eye around) |
| Cornea | colourless, transparent, front part of the sclera where light enters "window of the eye" |
| Pupil | The 'window' through which light enters the lens of the eye |
| Iris | Color ring around the pupil that contracts and relaxes regulating the amount of light entering the eye |
| Retina | Light rays converge here |
| Rods | Sensitive to bright light |
| Cones | Sensitive to colour |
| Optic Nerve | Nerve that transmits signals from the retina of the eye to the brain for interpretation |
| Blind Spot | area of the retina where the optic nerve and blood vessels connect - there are no rods or cones there |
| Ciliary Muscles | Bands of muscles behind the pupil that holds the lens in place |
| Normal Vision | Normal vision is 6/6 which indicates what can normally be seen at 6 metres. |
| Refractive Vision Problems | Vision defects that prevents an eye from focusing an image properly on the retina |
| Aqueous Humor | Directly behind the corneo in a transparent liquid |
| Lens | Thick double-convex tissue |
| Vitreous Humor | Behind the lens is a transprent jelly-like material |
| List in order the refracting parts of the eye (4 things) | 1. Cornea, 2. Aqueous Humor, 3. Lens, 4. Vitreous Humor |
| Retina is made up of two kinds of nerve cells: | Rods and Cones |
| We actually "See" with what organ? | The brain |
| Myopia | Can see nearby things but not distant objects |
| Hyperopia | Can see distant objects clearly but have trouble focussing on object close up |
| Astigmatism | A condition in which the corenea has a irregular curve. |
| Additive colour mixing | Process of adding together colours of light to produce other colours |
| Primary light colours | red, blue and green |
| Secondary light colours | created when primary light colours are combined - magenta yellow and cyan |
| Complementary light colours | Any two colours of light that produce white light when added together |