Chapter 10-2 Flashcards
Enzyme in tears that is antibacterial to reduce risk of eye infections
Lysozyme
Mucus membrane that lines the eyelids inner surface and covers anterior surface of eyeball
Conjunctiva
Function of the extrinsic muscle move eyes in various directions (6)
Superior rectus-rotate eye upward and toward midline
Inferior rectus-rotate eye downward and toward midline
Medial rectus-rotate eye inward toward midline
Lateral rectus-rotate eyes away from midline
Superior oblique-rotates eyes downward and away from midline
Inferior oblique-rotate upward and away from midline
Anterior, transparent window of eye that allows light rays to enter
Cornea
Outer white part of eye
Sclera
Vascular layer that contains pigment to keep inside of eye dark
Choroid coat
Thickest part, extends forward from choroid coat
Ciliary body
Transparent disk behind pupil for focusing
Lens
Ability of lens to change shape for focusing
Accommodation
Colored part of eye
Iris
Watery fluid between cornea and iris which helps nourish and maintain shape of cornea
Aqueous humor
Opening in iris for light to enter eye
Pupil
Thin delicate membrane which contains visual receptor cells
Retina
Depression in center of retina that produces sharpest vision
Fovea centralis
Region that lacks receptor cells
Optic disc
Transparent jelly like fluid in posterior cavity and helps maintain shape of eye
Vitreous humor
Bending of a beam of light as it passes from one medium to another
Light refraction
What’s the difference between convex and concave
Convex surface causes light waves to converge outward
Concave surface causes light waves to converge inward
Differ between rods and cones
Cones-sharp images; Rods-general outline of objects
Rods-hundred times more sensitive to light than Cones
Rods-colorless vision; cones-detect color
Sharpness or degree of detail the eye can see
Visual acuity
4 factors of visual acuity
Brightness, size of object, color of object, retinal area on which image of object falls
Light sensitive chemical in rods that breaks down into the protein opsin and retinal which is made from vitamin A
Rhodopsin
Name and define characteristics of color vision
Hue-sensory response made by our eyes to various wavelengths
Saturation-quality of color dependent on amount of white light present
Brightness-intensity of light waves reflected by surface
Purkinje shift is what
Shift from light to dark adaptation and vice versa
Carry over of visual impressions
After image
Eye disorder explain astigmatism
Abnormal curvatures of the surface of cornea or lens
Eye disorder explain myopia
Eyeball is too long from front to back
Eye disorder explain hyperopia
Eyeball is too short from front to back
Eye disorder explain presbyopia
Decline in usual accommodation with age
Eye disorder explain color blindness
Deficiency in color perception
Eye disorder explain cataract
Clouding of the lens
Eye disorder explain glaucoma
Amount of aqueous humor increases and eyeball becomes hard
Eye disorder explain conjunctiva
Inflammation of conjunction
