The eye

ajv09c's version from 2015-04-30 20:27

Section 1

Question Answer
eyeball is hollow
eyeball divided intotwo cavities; posterior cavity and anterior cavity
posterior cavitylarger, filled with vitreous humor
anterior cavitysmaller, filled with aqueous humor
anterior cavity consists of theanterior chamber and posterior chamber, anterior and posterior of the iris


Question Answer
three layers of the eyeouter fibrous layer, intermediate vascular layer, deep inner layer
outer fibrous layer consists ofsclera, cornea, corneal
sclerapart of fibrous layer, white of the eye
corneapart of fibrous layer, transparent anterior region
corneal limbuspart of fibrous layer, border between cornea and sclera


Question Answer
vascular layer (uvea) functions provedroute for blood vessels and lymphatics that supply tissues of eye
vacsular layer (uvea) functions regulateamount of light entering eye
vascular layer (uvea) secretes andreabsorbs aqueous humor that circulates within chambers of eye
vascular layer (uvea) controlsshape of lens; essential to focusing
vascular layer includesiris, ciliary body, choroid


Question Answer
iris containspapillary muscles; change diameter of pupil
diameter of the pupil changed bysympathetic and parasympathetic innervation by stimulating pupillary dilator or constrictor
cillary body containsciliary processes and ciliary muscle that attaches to suspensory ligaments of lens
ciliary muscle controllens position and shape
choroid deliversoxygen and nutrients to retina
pupillary dilator muscles extendradially away from edge of the pupil, contraction of the muscle enlarges the pupil


Question Answer
pupillary constrictor muscles are froma series of concentric circles around the pupil; when sphincter muscles contract diameter of pupil decreases
increased light intensityincreased parasympathetic stimulation, increased pupillary constriction
decreased light intensityincreased sympathetic stimulation; increased pupillary dilation
inner layer consists oftwo layers; outer inner layer
outer layer of inner eyecalled pigmented part- absorbs light that passes through the neural part (prevents rebounding of light)
inner layer of inner eyecalled neural part (retina)


Question Answer
neural part (retina) containsvisual receptors and associated neurons
rods and cones are photoreceptors
rodsdo not discriminate light colors; highly sensitive to light- used in low light (night)
conesprovide color vision; densely clustered in fovea, at center of macula
photoreceptors are closest to the choroid, rather than near the posterior cavity (vitreous chamber)
neural part type of cellsbipolar cells, horizontal cells, amacrine cells


Question Answer
neural part bipolar cellsneurons of rods and cones synapse with ganglion cells
neural part horizontal cellsextend across outer portion of retina
neural part amacrine cellscomparable to horizontal cell layer; where bipolar cells synapse with ganglion cells
horizontal and amercing cellsfacilitte or inhibit communication between photoreceptors and ganglion cells; alters sensitivity of retina
optic disc locationcircular region just medial to fovea
optic disc is the origin ofoptic nerve; blind spot located here
scotomasabnormal blind sports (located in other areas other than optic disc); may be caused by compression of optic disc, damage to photoreceptors, damage to visual pathway

Section 2

Question Answer
chambers of eye are the larger posterior cavity (vitreous chamber); smaller anterior cavity
what divides the chambers of the eyeciliary body and lens
smaller anterior cavity consists of anterior chamber-extends from cornea to iris; posterior chamber-between iris, ciliary body and lens