Chapter 14 definitions Flashcards
Eyeball consists of three layers in order from out to in
sclera, choroid, retina
sclera
white color, provides strength, structure and shape
cornea
transparent, allows light in
conjunctiva
thin mucous membrane covering the outer surface of the eye and lines the eyelids
choroid
dark blue vascular layer that supplies blood to the
optic nerve
attached to the retina, extends to the brain
iris
circular structure that gives eyes color
pupil
lets light in like a window
ciliary body
includes ____ muscles, these help lens change shape enabling us to focus (process called accomodation)
lens
clear firm transparent disk
retina
reception of visual impulses through the lens and the transmission of these impulses to the brain
Rods
Black and white
cones
color
optic nerve
gathers visual stimuli from the ganglion neurons and transmits this information to the brain for interpretation
aqueous humor
found in the posterior and anterior chambers. Nourishment for the lens and cornea (drains through a small opening called the Schlemm’s canal.)
vitreous humor
in addition to aqueous humor, the posterior chamber also contains this. A jellylike substance that fills the posterior chamber and gives shape to the eye
lacrimal glands
bathe, moisten, and lubricate the eye (tears contain a bacteria killing enzyme and wash away foreign debris
ear
responsible for hearing, balance, and equilibrium (composed of external, middle, and internal ear
external ear
composed of the auricle or pinna, which is the outer structure, collects sound waves and channels them into the external auditory canal.
external auditory canal
slender tube that leads to the middle ear. lined with modified sweat glands that secrete cerumen that traps tiny foreign particles
Tympanic membrane
inner end of the auditory canal, thin flat, irregularly shaped membrane called the eardrum
eustachian tube
connects the middle ear to the throat? Popping ears
Ossicles
includes malleus, incus, and stapes. TM vibrates these and causes them to move which sends vibrations to the inner ear
inner ear
labyrinth
cochlea
tiny, circular, snail shaped structure filled with fluid called perilymph
organ of corti
contains nerve endings called hair cells that transmit impulses to the auditory nerve
semicircular canals
located behind the ossicles and two windows, contain perilymph and endolymph. Together with the cochlea, these structures make up the vestibular system
Static vs dynamic equilibrium
a sense of balance when we are at rest vs in motion
