vision

where are the eye muscles attached to?

the sclera

function of the superior rectus?

elevates and adducts

function of the lateral rectus?

lateral movement

function of the medial rectus?

medial movement

function of the inferior oblique?

lateral rotates

function of the inferior rectus?

depresses

function of the superior oblique?

medially rotates

what duct and gland are located diagonally from each other?

lacrimal gland and nasolacrimal duct

the nasolacrimal duct if lower than?

lacrimal gland

what does the position of the nasolacrimal and lacrimal create?

flow of fluid across the eye

what do tears consist of?

water, salts, mucus, and protective enzymes

what do tears do for the eye?

lubricate the eye and keep pathogens from infecting it

what is the cornea?

transparent layer covering the iris

what’s the function of the cornea?

focuses light through the pupil to the retina and allows light to pass easily through it

what make it hard for the cornea to heal?

no blood vessels

what is the iris?

the colored part of the eye

what gives the iris its color?

melanin

what two parts does the iris separate into?

anterior and posterior chambers

what’s the function of the iris?

adjusts to the size of the pupil to allow different amount of light though the eye , constricting to allow in less light in bright environment and dilating in more light when light is scarce

what does the pupil allow?

light to enter the eye

what does the lens change?

shape to focus light on the retina

what does the ciliary body adapts to?

the lens shape for focusing light to adjust for objects at different distances

when does the pupillary dilator dilate?

when it receives parasympathetic inputs

when does the pupillary sphincter constrict?

when it receives sympathetic inputs

what does the sclera do?

maintain shape and ridigity of the eyeball and provides an attachment surface for the eye muscles

what does the choroid do?

provides nutrients to the retina and absorbs stray beams of light, contains a high abundance of melanin

what does the retina do?

houses the photoreceptors cells and some cells that process visual information

the retina contains photoreceptors called?

rods and cones

what does the photoreceptors do?

they change light signals into neural signals

rods can sense what?

dim light

cones can detect what?

color

how many rods?

120 million

how many cones?

6 million

what is the central part of the retinal with a high abundance of cones?

fovea centralis

what’s the function of the fovea centrals?

higher visual acuity

what is the blind spot?

the parts of the retina with no rods or cones

what the site where the optic nerve exits the eye/ axons of the retinal cells exits in the eye

the blind spot

function of the blind spot

cannot transducer any light from this region

what happens to the lens when the ciliary muscles contract?

the lens becomes more round and thicker

what is the fluid matrix in the eye>

vitreous humor

what is the function of the cilliary muscle?

helps the eye focus