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23 Cards in this Set
- Front
- Back
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The Eye |
Is the organ of vision |
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How does it detect light? |
Allows animals to detect light and convert into electrical impulses transferred along nerves |
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Structure of Eye |
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Iris |
Coloured muscles that surrounds your pupil Controls size of the pupil (contracting and relaxing) to let more or less light in |
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Retina |
Layer of receptors inside your eye Two types of light sensitive cell called RODS or CONES |
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Cornea |
Transparent part of your eye that covers iris and pupil and refracts light through pupil |
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Lens |
Biconvex structure behind your pupil that further refracts light to be focused on your retina, changed in ACCOMODATION |
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Ciliary Body |
Structure made of ciliary muscles and can contract and relax to change the shape of your lens during accomodation |
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Choroid |
Layer of eye between retina and sclera provides oxygen and nourishment to the cells of the retina |
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Fovea |
Specific part of the retina responsible for your sharpest vision. Half of the neurones that leave your eye come from this point |
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Sclera |
The white of your eye, outer layer and protects the rest of your eye |
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Optic Nerve |
Made from neurones that connect your eye to your brain. Electrical impulses from eyes to brain to let you see |
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Cones : Rods |
7 million : 75-150 million |
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Cones |
Require bright light to work properly and allow us to see in colour |
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Rods |
Work in low light intensity, colours are less vivid |
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Accommodation Diagram |
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Accomodation |
Lense in your eye can change shape and allow you to focus on objects |
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Accommodation : Near Objects |
Muscles contract which makes lens more convex. Lenses become shorter and fatter so you can focus |
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Accommodation: further away objects |
Ciliary muscles relax and lenses become longer and thinner |
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Hyperopia |
Long - sightedness Unable to correctly focus light on their retina and can not see objects close Eyeball is too short so cornea not curved enough and lens not thick enough |
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Hyperopia Diagrma |
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Myopia |
Short sightedness Cant see objects far from you |
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Myopia Diagram |
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