TO SEE OR NOT TO SEE THAT IS THE QUESTION
LIGHT Travels in waves ROYGBIV Colors are different wavelengths of light
Color blindness test
EYE DIAGRAM 1. Cornea-window of the eye 2. Aqueous humor-holds cornea away from eye 3. Pupil-lets light in 4. Iris-controls amount of light 5. Ciliary body-controls iris 6. Lens-focuses light on back of eye 7. Vitreous body-gives eye shape 8. Retina-contains light sensitive nerves 9. Sclera-white of the eye-reflects light away 10. Optic nerve-brings message to brain 11. Fovea centralis-center of vision 12.
Retina Contains nerves called rods and cones Rods sense light and are very sensitive (low threshold) Cones sense color but not very sensitive (higher threshold)
Function of Rods In rods there is a pigment called rhodopsin When a photon of light hits it, it breaks down into retinal and opsin changing polarity and bringing a message to the brain if bright light is present, it takes time to replace the rhodopsin, bleaching occurs About 10,000 rods converge to one integrative neuron in the brain
Three colors primary colors of light Lack of one or more=colorblindness Center of vision (fovea) is all cones Each cone has its own integrative neuron in the brain CONES
Cone densities and spectrum Average adult has 16% blue, 74% red and 10% green cones
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