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25 Cards in this Set
- Front
- Back
Focal length |
Distance from the center of the lens to the focal point |
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Focal point |
Point where light rays converge |
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Concave lens |
Scattered light rays |
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Lens chaos controlled by |
Ciliary muscle |
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Ciliary muscles relax |
Lens get flat |
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Ciliary muscles contract |
Lens get bulgy |
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Accommodation |
Eye adjust shape of lens to keep objects in focus |
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Presbyopia |
Loss of accommodation |
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Myopia Hyperopia |
Near sightedness Far sightedness |
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Uv, x-rays, gama rays |
Too much for human eyes and can damage |
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Infrared, microwaves, radio waves |
Not enough energy for humans to see |
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2 types of photoreceptors |
Rods (dark) and cones (light) |
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3 types of cones |
Red, blue and green Allow my you to see axons |
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White |
Blue green and red at the same time |
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Black |
None |
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Gray |
Stimulate a little of each color the same time |
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Astigmatisms |
Córnea that is miss shaped not a perfect dome |
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When image hits the retina they appear |
Upside down |
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Ganglion cells send axons to the |
Brain |
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Retinal photoreceptors layer (light travels to get to back of retina) |
Ganglion, amacrine, bipolar, horizontal, and rods/cones |
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Rods only have one type of visual pigments |
Rhodopsin (opsin- protein and retinal-derivative of vitamin A) |
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Process known as bleaching |
Protein hits retinal, change shape and the activated retinal no longer binds to opsin and released from pigment |
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In the light |
Less glutamate and no inhibition of “on bipolar cells” Retina changes shape which lowers transduction and closes CNG channels “Off bipolar cells” are stimulated |
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In the dark |
High GMP keeps CNG channels open Cells release neurotransmitter when not stimulated (backwards) Glutamate- “on bipolar cells” -40mV |
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Visual fields |
Make edges and extenuate the shape |