what is the major metabolic fuel for the eye?
what do retinol and retinoic acid prevent in the cornea?
the synthesis of keratin
what is the use of retinyl phosphate in the cornea?
it is required for the production of glycoproteins
what is the path of the aqueous humor after it is procuded by the ciliary process?
enters posterior chamber --> flows through pupil into anterior chamber --> drained through trabecular meshwork--> leaves via Schlemm's canal
what forms the blood aqueous barrier?
tigh junctions between nonpigmented epithelium (NPE) and nonleaky enothelial cells of iris capillaries
what is the photoreceptor pigment in rod cells?
rhodopsin (opsin and 11-cis-retinal)
what are the photoreceptor pigments in cone cells?
red, green or blue pigment
what is the function of cones in the retina?
sensing/seeing color and acute vision
what is the function of rods in the retina?
sensing/seeing night and peripheral vision
when are the photoreceptors depolarized?
in the resting state/dark-adapted state
when are the photoreceptors hyperpolarizes?
in the activated state/light-excited state
in what 3 ways is lutein and zeaxanthine believed to prevent AMD?
1. filtering out blue light
2. protect photoreceptors from oxidation
3. protect blood vessels supplying the macular region
Biochemistry of the Eye