What is the function of the eyebrows?
Help shield eyes.
What is the function of eyelids?
Barrier that completely protects the eye; everytime we blink our eyelids clean our eye.
What is the function of tarsal glands?
Keep eyes moist.
What is conjunctivitis?
Pink eye; inflammation of the eye.
What is the function of the lacrimal apparatus?
Makes & drains tears in the eye.
What is the function of the lacrimal gland?
secretes tears with lysozymes & antibodies
What are the 3 layers of the eye?
Inner Sensory Layer(retina)
What are the sub parts of the Fibrous Layer?
Sclera & Cornea
What is the function of the iris?
Controls size of pupil; controls amount of light into eye.
What 3 nuerons make up the inner sensory layer?
Photoreceptors(Cones & rods)
What is the function of rods?
dim light receptors; night blindness; color
What is the function of cones?
colorblindness; black & white
What is the optic disc?
Describe distant vision:
light rays are straighter, ciliary muscles relax and pull ligaments taught, lens is pulled flat and light focuses.
Describe close vision:
light rays are more angled, ciliary muscles contract and ligaments relax, lens assumes more oval shape to focus light on correct area of retina.
What is Cataracts?
Cloudy appearance in eye.
What is astigmatism?
reflects light in wrong way in eye.
What is the pathway of light?
What is the pathway of nerve impulses?
photoreceptors-->bipolar cells-->ganglion cells-->optic nerve-->optic chiasma-->optic tracts-->visual cortex
What is otitis externa(swimmers ear)?
Small bacterial infection
What is motion sickness?
Caused my over stimulation of the motion receptors; when eyes and ears disagree.
What is the sound pathway?
auricle/pinna-->external acostic meatus--?ypmpanic membrane-->malleous-->inclus-->stapes-->oval window-->cochlea-->hair cells-->vestibulocochlear nerve-->auditory cortex