Page 932 - Atlas of Histology with Functional Correlations

SECTION 1 • Visual System

Eyes are located in protective orbits in the skull

Visual images are conveyed from eye to brain via optic nerves

EYE LAYERS

Sclera is the outer layer of eye and is composed of dense connective tissue
Internal to sclera is the middle or vascular layer uvea that nourishes the retina
and the eyeball
Uvea consists of pigmented choroid, ciliary body, and iris

Retina is the innermost lining of eye; posterior three-quarters of retina is
photosensitive
Retina terminates anteriorly at ora serrata, which is a nonphotosensitive part

of retina

WHOLE EYE

Sclera maintains the rigidity of the eyeball and is the white of the eye
Anteriorly, sclera is modified into transparent cornea through which light
enters eye
Choroid and ciliary body are adjacent to sclera

Ciliary processes from ciliary body attach lens by suspensory ligament or
zonular fibers
Iris partially covers the lens and is the colored part of the eye
Radial smooth muscle forms an opening in the iris, called the pupil

EYE CHAMBERS

Anterior chamber located between cornea, iris, and lens
Posterior chamber is a small space between iris, ciliary process, zonular
fibers, and lens

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