1. 7.5.g Students know how to relate the structures of the eye and ear to their functions. 7.6.b Students know that for an object to be seen, light emitted by or scattered from it must be detected by the eye. 7.6.e Students know light is a mixture of many wavelengths (colors) and that retinal cells react differently to different wavelengths.

2. Vision Eyes respond to the stimulus of light converting that stimulus into impulses that your brain interprets, enabling you to see. Key concept: When light from an object enters your eye, your eye sends a signal to your brain and you see the object. The pupil gets bigger to allow in more light and smaller to allow in less light Iris is the color of your eye- most people have brown eyes

3. Cornea- the transparent front surface of the eye that protects it Pupil- opening through which light enters the inside of the eye Iris- a ring of muscle that contracts and expands to change the size of the pupil Retina- a layer of cells that lines the inside of the eyeball Rods- contain pigment that responds to small amounts of light Cones- respond to color (best in bright light), detecting red, green, or blue light Lens- bends light to form an upside-down image on the retina

4. Correcting Vision  Key concept: Concave lenses are used to correct nearsightedness. Convex lenses are used to correct farsightedness. Nearsighted- person can see nearby things clearly Problem: focal point in front of retina Farsighted- person can see distant objects clearly Problem: focal point behind retina Eye Video