Senses: Eyes Flashcards
the mucus membranes that lines eyelids & covers the sclera -
Conjuctiva
nonvascular, transparent
focuses light rays - refracts
cornea
a white coat of tough fibrous tissue
- gives support & protection
- the “white” of the eye
sclera
in front of the lens
- it is filled with aqueous humor
- Constant pressure needs to be maintained to prevent glaucoma
anterior chamber
it is a watery fluid in the anterior chamber
-also is transparent
aqueous humor
A hole through which light enters the eye
pupil
it is a doughnut shaped muscle
- regulates the amount of light entering the pupil
iris
it’s secretes aqueous humor
Ciliary Body - Ciliary Process
it contracts to change the lens shape and focus on near objects
ciliary muscle
aqueous humor returns the venous blood system through this opening
-adjusts pressure of the ehe
canals of schlemm
constructed of layers of protein is held in position by means of a suspensory ligament
- refracts
- focuses
lens
it’s behind the lens
- is filled with the vitreous humor
posterior chamber
a jelly-like fluid which functions to refracture light and keep retina in place
vitreous humor
it’s function is converting images to impulse
it’s nervous layer has three zones of neurons
retina
three zones of neurons of the retina:
Photo receptor cells
bipolar cells
ganglion cells
-vison/black and white
rods
daytime & color vision
cones
…….. has the greatest concentration in there for the area of the greatest visual acuity and bright light
fovea centrals
they pick up the impulses from the rods or cones and sends to the ganglion cells
bipolar cells
this zone of neurons passes the impulse to the optic nerve
ganglion cells