Ch 10 Special Senses

Accommodation

When the muscle controls the shape of the eye for vision.

Anterior chamber

Filled with a watery fluid called aqueous humor fluid.

Anvil (incus)

Tiny bones in the ear.

Aqueous humor

Constantly filtered and drained and gives nourishment.

Cerumen

Wax like oily substance.

Choroid coat

Middle layer of the eye. Contains blood vessels to nourish the eye.

Ciliary body

Consists of the smooth muscle that controls the shape of the eye.

Cochlea

Snail-shaped structure where sound vibrations are converted into nerve impulses.

Cochlear duct

The semicircular canals and auditory nerves.

Color blindness

Inability to distinguish colors.

Cones

Allows for color.

Cornea

The very front of the eye.

Deviated nasal septum

A condition in which there is a bend in the cartilage structure of the septum.

Eustachian tube

Serves to equalize the air pressure in the middle of the ear with that of the outside atmosphere.

Extrinsic muscle

Muscles responsible for moving the eye within the orbital socket.

Eye strain

Burning, tightness, sharp or dull pain, water, blurry vision and head aches caused by discomfort.

Fovea centralis

Contains the cones for color vision.

Hammer (malleus)

Tiny bone found in the ear.

Iris

A colored muscular layer that surrounds the eye.

Lens

Crystalline structure located behind the iris and pupil.

Macula lutea

A yellow disc

M�ni�re's disease

A rare condition that affects the semicircular canals of the inner ear causing dizziness.

Miotic

Constrict the pupil and increase outflow of aqueous humor.

Myringotomy

An opening made in the tympanic membrane.

Nasal polyp

Soft, noncancerous growths in the lining of the nasal passages or sinuses.

Night blindness

A condition that makes it difficult to see at night.

Optic disc (blind spot)

Contains no rods or cones and therefore is unable to convert images.

Organ of corti

Located within the cochlea of the inner ear. Receptor for hearing.

Otitis media

An infection of the middle of the ear.

Ostosclerosis

A condition in which the stapes bone in the middle of the ear first becomes spongelike and then hardens.

Oval window

Located just under the base of the stapes and is the membrane that separates the middle ear from the inner ear.

Pinna

Collects sound waves and directs the to auditory canal.

Posterior chamber

Helps to situate the lens along with the anterior chamber.

Presbycusis

Sensorineural hearing loss which involves changes in the neutral, sensory, and mechanical structure in the inner ear.

Pupil

Circular opening in the choroid coat.

Retina

Innermost part of the eye. Located between posterior chamber and choroid coat.

Rhinitis

Inflammation of the lining of the nose that may cause nasal congestion, drainage, sneezing, or itching.

Rods

Sensitive to dim light.

Sclera

The outer layer of the eye or the white of the eye.

Semicircular canal

Contains liquid and hairlike cells that bend when the liquid is set in motion.

Stirrup (stapes)

Tiny bones in the ear.

Suspensory ligament

Holds he lens in place.

Tinnitus

Ringing in the ears.

Tympanic membrane

Eardrum.

Vertigo

Dizziness.

Vitreous humor

A transparent jellylike substance, fills the posterior chamber. Helps to maintain shape.