eye anatomy Flashcards
- lateral end of eye
- produces lacrimal fluid
lacrimal gland
- drain lacrimal fluid
from eyes
Lacrimal canals
provides passage of lacrimal fluid towards nasal cavity
lacrimal sac
Muscles attached to the outer surface of the eye
Produce eye movements
extrinsic eye muscles
moves eye laterally
lateral rectus
moves eye medially
medial rectus
elevates eye and rolls it medially
superior rectus
, depresses eye and rotates it laterally
inferior rectus
produce gross movement and allow the eye to follow a moving object
rectus muscles
The wall is composed of three tunics
fibrous
vascular
nervous/sensory
outermost tunic
Thick white connective tissue layer
Seen anteriorly as the “white of the eye”
sclera
Transparent, central anterior portion
Allows for light to pass through
Most exposed part
cornea
part of the fibrous tunic
Repairs itself easily
the only human tissue that can be transplanted without fear of rejection
When touched it will cause blinking and tearing of eyes
cornea
Blood-rich nutritive tunic
Pigment prevents light from scattering
Modified anteriorly into two structures (ciliary body and iris)
vascular
Pigmented layer that gives eye color
With circularly and radially arranged smooth muscles
iris
– rounded opening in the iris
pupil
Innermost tunic
Extends anteriorly to the ciliary body
Contains photoreceptor cells
sensory tunic retina
Most are found towards the edges of the retina
Allow dim light vision and peripheral vision
Perception is all in gray tones
rods
Allow for detailed color vision
Fovea centralis
cones
area of the retina with only cones
- Area with great or sharpest vision
fovea centralis
No photoreceptor cells are at the
optic disk, or blind spot
Biconvex crystal-like structure
Held in place by a suspensory ligament attached to the ciliary body
lens
Watery fluid found in chamber between the lens and cornea
Similar to blood plasma
aqueous humor
Internal Eye Chamber Fluid
Helps maintain intraocular pressure
Provides nutrients for the lens and cornea
aqueous humor
aqueous humor is Reabsorbed into venous blood through the
canal of Schlemm
Gel-like substance behind the lens
Keeps the eye from collapsing
Lasts a lifetime and is not replaced
vitreous humor
