click below
click below
Normal Size Small Size show me how
phys special senses
physiology of special senses
| Question | Answer |
|---|---|
| refractive power of a lens | measured in diopters; equals the reiprocal of the focal distance in meters |
| emmetropia | normal-light focuses on the retina |
| hypertropia | far sighter- light focuses behind the reitna and is correctid with a convex lens |
| myopia | near sighted-light focuses in front of the retina and is corrected with a biconcave lense |
| astigmatism | curvature of the lens is not uniform and is corrected with a cylindric lens |
| presbyopia | loss of accommodation power of the lens corrected with convex lens |
| pigment layer | contains melanin and absorbs stray light |
| photoreceptor layer | rods and cones |
| simple cells | respond to bars of light that have th correct position and orientation |
| complex cells | respond best to moving bars or edges of light with the correct orientation |
| hypercomplex cells | respond best to lines with particular length and to curves and angles |