DHO chapter 7-7: special senses

vestibule

any of various bodily cavities leading to another cavity (as of the ear or vagina)

pupil

the opening in the iris that regulates the amount of light entering the eye

ossicles

three small bones in the middle ear: the malleus (hammer), the incus (anvil), and the stapes (stirrup)

choroid coat

" the middle layer of the eye"; it is the interlaced with many blood vessels, which nourish the eyes

refracts

(bends) light rays so the rays focus on the retina

cochlea

a coiled, bony, fluid-filled tube in the inner ear through which sound waves trigger nerve impulses

conjunctiva

a transparent membrane covering the eyeball and under surface of the eyelid

auditory canal

either of the passages in the outer ear from the auricle to the tympanic membrane

retina

innermost layer that perceives and transmits light to the optic nerve

lacrimal glands

located on the underside of the upper eyelid just above the outer corner of each eye; secretes lacrimal fluid (tears)

iris

muscular diaphragm that controls the size of the pupil

semicircular membrane

passages in the ear associated with maintaining equilibrium

organ of corti

structure on the surface of the basilar membrane that contains the receptor cells for hearing

vitreous humor

the clear colorless transparent jelly that fills the posterior chamber of the eyeball

auricle

the externally visible cartilaginous structure of the external ear

pinna

the externally visible cartilaginous structure of the external ear

aqueous humor

the limpid fluid within the eyeball between the cornea and the lens

cornea

transparent anterior portion of the outer covering of the eye

lens

transparent structure behind the pupil that bends and focuses light rays on the retina

eustachian tube

tube connecting the middle ear to the pharynx (throat)

sclera

whitish fibrous membrane (albuginea) that with the cornea forms the outer covering of the eyeball