Special Sense - Eye Flashcards
What nerve is responsible for the constriction of the pupil?
Occulomotor n. (PSNS)
List the ten layers of the retina photosensitive area
Pigment cell layer, layer of rods/cones, outer limiting membrane, outer nuclear layer, outer plexiform layer, inner nuclear, inner plexiform layer, ganglion cell layer, layer of optic nerve, inner limiting membrane
When are rods used?
Low light levels, black/white vision
When are cones used?
Light sensitive, high visual acuity, color vision
The site where the optic nerve emerges from the retina is referred to by what terms?
Optic disc, optic papilla, blind spot
Which two layers fuse to create the retina in the embryo?
Outer pigment layer, inner nervous layer
The (x) is continuous with the (y) mater which surrounds the optic nerve
Sclera (x), dura (y)
Abnormal aqueous humor drainage and increased intraoccular pressure is characteristic of what pathology?
Glaucoma
What are the layers of the eye (not including the vitreous body)
Outer fibrous, middle vascular, inner nervous layer
Trace the pathway of light in order for vision to take place
Cornea, anterior chamber, pupil, lens, viterous body, retina
What is Tenon’s space and what does it allow the eye to do?
Space between episcleral layer and substantia propria, provides site for eye muscle attachment, allows eye to freely rotate
Which nerve innervates the cornea?
Opthalmic n. (V1)
List and describe the layers of the cornea
Anterior corneal epithelium (StSq, microvilli), Bowman’s membrane (collagen fibers, no cells), corneal stroma (regular arrangement of tropocollagen type I, III, V, VI), Descemet’s membrane, corneal endothelium (SiSq)
List and describe the layes of the choroid
Retinal pigment epithelium, Bruch’s membrane (collagen, elastic fibers), vascular choroid (incomplete fenestrations, supply outer few layers of retina), loose CT
What functions does the retinal pigment layer possess?
Esterification of vitamin A, synthesize melanin, phagocytose shed tips of rods/cones, blood-retinal barrier
Muller cells serve to support (x), extending from the (y) to the (z)
Retinal neurons/fibers (x), external limiting membrane (y), internal limiting membrane (z)
Besides rods, cones and Muller cells, what cells are present in the retina?
Bipolar, ganglion, horizontal, amacrine cells
What structure can be described as a shallow depression just lateral to the optic disc and possesses the zone of greatest acuity?
Fovea centralis
What structure can be described as a yellow pigmented zone which surrounds the fovea centralis?
Macula lutea
What are the two basic layers of the retina?
Outer retinal pigment epithelium, inner sensory retina (neural retina)
Would the body mount an immune response to a corneal transplant? Why or why not?
No, no vasculature in cornea
What is the function of corneal endothelium?
Dehydrate corneal stroma to allow for clear vision
Separation of the outer pigment and inner nervous layer during embryogenesis results in what pathology?
Retinal detachment
If retinal detachment is not repaired, what may result?
Degeneration of rods/cones
If resistance is noted within the aqueous humor drainage system, what pathology may occur?
Increased intraoccular pressure
What is the normal intraoccular pressure?
10-22 mmHg
As the sclera is an extension of the dura mater, it is made up of what type of CT?
Dense CT (collagen type I, elastic fibers)
What are the layers of the sclera?
Episcleral layer, substantia propria, suprachoroidal lamina