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HBS 2.4 Key Terms


Accommodation the automatic adjustment of the eye for seeing at different distances affected chiefly by changes in the convexity or the crystalline lens
Astigmatism a defect of an optical system causing rays from a point to fail to meet a focal point resulting in a blurred and imperfect image
blind spot the small circular area in the retina where the optic nerve enters the eye that is devoid of rods and cones and is insensitive to light
cone any of the conical photosensitive receptor cells of the vertebrate retina that function in color vision
cornea the transparent part of the coat of the eyeball that covers the iris and pupil and admits light to the interior
Depth perception the ability to judge the distance of objects and the spatial relationship of objects at different distances
Hyperopia a condition in which visual images come to a focus behind the retina of the eye and vision is better for distant than for near objects (can't see close objects well)
iris the opaque muscular contractile diaphragm that is suspended in the aqueous humor in front of the lens of the eye, is perforated by the pupil and is continuous peripherally with the ciliary body, has a deeply pigmented posterior surface which excludes the
Myopia a condition in which the visual images come to a focus in front of the retina of the eye because of defects in the refractive media of the eye or of abnormal length of the eyeball resulting especially in defective vision of distant objects
optic nerve transmits visual information from retina to the brain
pupil the opening in the iris, which admits light into the interior of the vertebrate eye
Refraction the deflection from a straight path undergone by a light or a wave of energy in passing obliquely from one medium into another in which its velocity is different
rod any of the long rod-shaped photosensitive receptors in the retina responsive to faint light
Created by: Escalena1