Ch. 7.7 Special Senses Key Terms
aqueous humor
- A clear, watery fluid that fills the space between the cornea and iris.
Conjunctiva
- A mucous membrane that lines the eyelids and covers the front of the eye to provide additional protection and lubrication.
Lens
- A circular structure located behind the pupil and suspended in position by ligaments.
Refracts
- Bending of the bones.
Vestibule
- acts as the entrance to the two other parts of the inner ear.
auditory canal
- Special glands in the canal produce cerumen which is a wax that protects the ear.
Cornea
- circular, transparent part of the front of the sclera. It allows light rays to enter the eye.
organ of corti
- a receptor of sound waves. The organ of Corti transmits the impulses from sound waves to the auditory nerve.
Retina
- The innermost layer of the eye and is made of many layers of nerve cells, which transmit the light impulses to the optic nerve.
vitreous humor
- The jellylike substance that fills the area behind the lens. It helps maintain the shape of the eyeball and also refracts light rays.
Auricle
- the visible part of the ear
eustachian tube
- The middle ear is connected to the pharynx, or throat, by a tube called the eustachian tube. This tube allows air to enter the middle ear and helps equalize air pressure on both sides of the tympanic membrane.
Ossicles
- Small bones
Sclera
- The outermost layer is the tough connective tissue called the sclera. It is frequently referred to as the "white" of the eye. The sclera maintains the shape of the eye.
choroid coat
- The middle layer of the eye and it is interlaced with many blood vessels that nourish the eyes.
Iris
- The colored portion of the eye which is located behind the cornea on the front of the choroid coat.
Pinna
- Elastic cartilage covered by the skin. It leads to a canal, or tube, called the auditory canal.
semicircular canals
- contain a liquid and delicate, hairlike cells that bend when the liquid moves with head and body movements. Impulses sent from the semicircular canals to the cerebellum of the brain help to maintain our sense of balance and equilibrium.
Cochlea
- shaped like a snail's shell, contains delicate, hairlike mechanoreceptor cells
lacrimal glands
- In the eye which produces tears which constantly moisten and cleanse the eye.
Pupil
- The opening of the center of the iris.
tympanic membrane
- separates the outer ear from the middle ear. It vibrates when sound waves hit it and transmits the sound waves to the middle ear.