CLASSWORK : Ch. 7.7 Special Senses Key Terms
aqueous humor
aqueous humor: A clear, watery fluid that fills the space between the cornea and iris. It helps maintain the forward curvature of the eyeball and refracts light rays.
conjunctiva
conjunctiva: A mucous membrane that lines the eyelids and covers the front of the eye to provide additional protection and lubrication.
lens
lens: A circular structure located behind the pupil. It refracts (bends) light rays so they focus on the retina.
refracts
refracts: Bends light rays.
vestibule
vestibule: The first section of the inner ear, which acts as the entrance to the two other parts of the inner ear (the cochlea and semicircular canals).
auditory canal:
auditory canal: (Also called the external auditory meatus) The canal, or tube, that sound waves travel through from the pinna to the tympanic membrane.
cornea
cornea: A circular, transparent part of the front of the sclera that allows light rays to enter the eye.
organ of Corti: A receptor of sound waves located in the cochlea. It contains delicate, hairlike cells that transmit impulses from sound waves to the auditory nerve.
retina
retina: The innermost layer of the eye, made of many layers of nerve cells (including rods and cones) that transmit light impulses to the optic nerve.
vitreous humor:
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:
auricle: (Also called the pinna) The visible part of the ear, made of elastic cartilage covered by skin.
eustachian tube
eustachian tube: A tube that connects the middle ear to the pharynx (throat). It allows air to enter the middle ear and helps equalize air pressure on both sides of the tympanic membrane.
ossicles
ossicles: Three small bones in the middle ear (malleus, incus, and stapes) that are connected and transmit sound waves from the tympanic membrane to the inner ear.
sclera
sclera: The outermost, tough connective tissue layer of the eye; the "white" of the eye. It maintains the shape of the eye.
choroid coat
choroid coat: The middle layer of the eye, which is interlaced with many blood vessels that nourish the eyes.
iris
iris: The colored portion of the eye, located behind the cornea. It contains two muscles that control the size of the pupil and regulate the amount of light entering the eye.
pinna
pinna: (Also called the auricle) The visible part of the ear.
semicircular canals
semicircular canals: Canals in the inner ear that contain a liquid and delicate, hairlike cells. Impulses sent from these canals to the cerebellum help maintain balance and equilibrium.
cochlea
cochlea: A part of the inner ear, shaped like a snail's shell, which contains the organ of Corti.
lacrimal glands
lacrimal glands: Glands in the eye that produce tears, which constantly moisten and cleanse the eye.
pupil
pupil: The opening in the center of the iris.
tympanic membrane
tympanic membrane: (Also called the eardrum) It separates the outer ear from the middle ear and vibrates when sound waves hit it.