Chapter 17-The Special Senses Flashcards
A saclike dilation of a canal or duct
Ampulla
The watery fluid, similar in composition to the cerebrospinal fluid, that fills the anterior cavity of the eye
Aqueous humor
An irregularity of the lens or cornea of the eye causing the image to be out of focus and producing fault vision
Astigmatism
One of the three small bones of the middle ear called the malleus, incus, and stapes
Auditory ossicle
The tube that connects the middle ear with the nose and nasopharynx region of the throat. Also called the eustachian tube or pharyngotympanic tube
Auditory tube
A membrane in the cochlea of the internal ear that separates the cochlear duct from the scala tympani and on which the spiral organ (organ of Corti) rests
Basilar membrane
Area in the retina at the end of the optic (II) nerve in which there are no photoreceptors
Blind spot
A series of cavities within the petrous portion of the temporal bone forming the vestibule, cochlea, and semicircular canals of the inner ear
Bony labyrinth
Loss of transparency of the lens of the eye or its capsule or both
Cataract
Waxlike secretion produced by the ceruminous glands in the external auditory meatus (ear canal)
Cerumen or ear wax
A modified sudoriferous (sweat) gland in the external auditory meatus that secretes cerumen
Ceruminous gland
One of the vascular coats of the eyeball
Choroid
One of the three parts of the vascular tunic of the eyeball, the others being the choroid and the iris; includes the ciliary muscle and the ciliary processes
Ciliary body
A winding, cone-shaped tube forming a portion of the inner ear and containing the spiral organ (organ of Corti)
Cochlea
The membranous cochlea consisting of a spirally arranged tube enclosed in the bony cochlea and lying along its outer wall
Cochlear duct or scala media
The type of photoreceptor in the retina that is specialized for highly acute color vision in the bright light
Cone
The delicate membrane covering the eyeball and lining the eyes
Conjunctiva
A synaptic arrangement in which the synaptic end bulbs of several presynaptic neurons terminate on one postsynaptic neuron. The medial movement of the two eyeballs so that the both are directed toward a near object being viewed in order to produce a single image
Convergence
The nonvascular, transparent fibrous coat through which the iris of the eye can be seen
Cornea
A crest or ridged structure. A small elevation in the ampulla of each semicircular duct that contains receptors for dynamic equilibrium
Crista
A mass of gelatinous material covering the hair cells of a crista; a sensory receptor in the ampulla of a semicircular canal stimulated when the head moves
Cupula
The maintenance of body position, mainly the head, in response to sudden movements such as rotation
Dynamic equilibrium
The primary germ layer that gives rise to the nervous system and the epidermis of skin and its derivatives
Ectoderm
A primary germ layer of the developing embryo; gives rise to the gastrointestinal tract, urinary bladder, urethra, and respiratory tract
Endoderm
A curved tube in the temporal bone that leads to the middle ear
External auditory canal or external auditory meatus
The outer ear, consisting of the pinna, external auditory canal, and tympanic membrane (eardrum)
External ear
The hairy ridge superior to the eye
Eyebrow
The superficial coat of the eyeball, made up of the posterior sclera and the anterior cornea
Fibrous tunic
One of the conical projections that are distributed in parallel rows over the anterior two-thirds of the tongue and lack taste buds
Filiform papilla
A mushroomlike elevation on the upper surface of the tongue appearing as a red dot; most contain taste buds
Fungiform papilla
Usually, a group of neuronal cell bodies lying outside the central nervous system
Ganglion
An eye disorder in which there is increased intraocular pressure due to an excess of aqueous humor
Glaucoma
The inner ear of the labyrinth, lying inside the temporal bone, containing the organs of hearing and balance
Internal ear
Pressure in the eyeball, produced mainly by aqueous humor
Intraocular pressure
The colored portion of the vascular tunic of the eyeball seen through the cornea that contains circular and radial smooth muscle
Iris
Intricate communicating passageway, especially in the internal eear
Labyrinth
A duct, one on each eyelid, beginning at the punctum at the medial margin of an eyelid and conveying tears medially into the nasolacrimal sac
Lacrimal canal
Secretory cells, located at the superior anterolateral portion of each orbit, that secrete tears into excretory ducts that open onto the surface of the conjuctiva
Lacrimal gland
The superior expanded portion of the nasolacrimal duct that receives the tears from a lacrimal canal
Lacrimal sac
A transparent organ constructed of proteins (crystallins) lying posterior to the pupil and iris of the eyeball and anterior to the vitreous body
Lens
A bactericidal enzyme found in tears, saliva, and prespiration
Lysozyme
A discolored spot or a colored area. A small, thickened region on the wall of the utricle and saccule that contains receptors for static equilibrium
Macula
The yellow spot in the center of the retina
Macula lutea
One of the three small bones of the middle ear called the auditory ossicle, incus, and stapes
Malleus
The part of the labyrinth of the internal ear that is located inside the bony labyrinth and separated from it by the perilymph; made up of the semicircular ducts, the saccule and utricle, and the cochlear duct
Membranous labyrinth
An embryonic connective tissue from which all other connective tissues arise
Mesenchyme
A small, epithelial-lined cavity hollowed out of the temporal bone, separated from the external ear by the eardrum and from the internal ear by a thin bony partition containing the oval and round windows; extending across the middle ear are the three auditory ossicles.
Middle ear or tympanic cavity
The central pillar or column of the cochlea
Modiolus
Defect in vision in which objects can be seen distinctly only when very close to the eyes; nearsightedness
Myopia
A canal that transports the lacrimal secretion (tears) from the nasolacrimal sac in the nose
Nasolacrimal duct
A mass of gray matter containing cell bodies of neurons that form synapses with neurons of the olfactory (I) nerve, lying inferior to the frontal lob of the cerebrum on either side of the crista galli of the ethmoid bone
Olfactory bulb
A bipolar neuron with its cell body lying between supporting cells located in the mucous membrane lining the superior portion of each nasal cavity; transduces odors into neural signals
Olfactory receptor
A bundle of axons that extends from the olfactory bulb posteriorly to olfactory regions of the cerebral cortex
Olfactory tract
The study of structure, function, and diseases of the eye
Ophthalmology
A crossing point of two branches of the optic (II) nerve, anterior to the pituitary gland.
Optic chiasm
A small area of the retina containing openings through which the axons of the ganglion cells emerge as the optic (II) nerve
Optic disc or blind spot
A bundle of axons that carry nerve impulses from the retina of the eye between the optic chiasm and the thalamus
Optic tract
The irregular margin of the retina lying internal and slightly posterior to the junction of the choroid and ciliary body
Ora serrata
A particle of calcium carbonate embedded in the otolithic membrane that functions in maintaining static equilibrium
Otolith
Thick, gelatinous, glycoprotein layer located directly over hair cells of the macula in the saccule and utricle of the internal ear
Otolithic membrane
The branch of medicine that deals with the diagnosis and treatment of diseases of the ears, nose, and throat
Otorhinolaryngology
A small, membrane-covered opening between the middle ear and inner ear into which the footplate of the stapes fits
Oval window
A small nipple-shaped projection of elevation
Papilla
The fluid contained between the bony and membranous labyrinths of the inner ear
Perilymph
A substance that can absorb light and undergo structural changes that can lead to the development of a receptor potential
Photopigment
The projecting part of the external ear composed of elastic cartilage and covered by skin and shaped like the flared end of a trumpet
Pinna or auricle
A loss of elasticity of the lens of the eye due to advancing age with resulting inability to focus clearly on near objects
Presbyopia
A hole in the center of the iris, the area through which light enters the posterior cavity of the eyball
Pupil
The deep coat of the posterior portion of the eyeball consisting of nervous tissue (where the process of vision begins) and a pigmented layer of epithelial cells that contact the choroid
Retina
One of the two types of photoreceptor in the retina of the eye; specialized for vision in dim light
Rod
A small opening between the middle and internal ear, directly inferior to the oval window, covered by the secondary tympanic membrane
Round window
The inferior and smaller of the two chambers in the membranous labyrinth inside the vestibule of the internal ear containing a receptor organ for static equilibrium
Saccule
The inferior spiral-shaped channel of the bony cochlea, filled with perilymph
Scala tympani
The superior spiral-shaped channel of the bony cochlea, filled with perilymph
Scala vestibuli
The white coat of fibrous tissues that forms the superficial protective covering over the eyeball except in th emost anterior portion; the posterior portion of the fibrous tunic
Sclera
A circular venous sinus located at the junction of the sclera and the cornea through which the aqueous humor drains from the anterior chamber of the eyeball into the blood
Scleral venous sinus or canal of Schlemm
An exocrine gland in the dermis of the skin, almost always associated with a hair follicle, that secretes sebum
Sebaceous gland or oil gland
Three bony channels (anterior, posterior, lateral) filled with perilymph, in which lie the membranous semicircular canals filled with endolymph. They contain receptors for equilibirum
Semicircular canals
The membranous semicircular canals filled with endolymph and floating in the perilymph of the bony semicircular canals; they contain cristae that are concerned with dynamic equilibrium
Semicircular ducts
The organ of hearing, consisting of supporting cells and hair cells that rest on the basilar membrane and extend into the endolymph of the cochlear duct
Spiral organ or Corti
The maintenance of posture in response to changes in the orientation of the body, mainly the head, relative to the ground
Static equilibrium
A fold of peritoneum extending from the surface of the ovary to the pelvic wall
Suspensory ligament
Sebaceous (oil) gland that opens on the edge of each eyelid
Tarsal gland or Meibomian gland
A thin, elongated sheet of connective tissue, one in each eyelid, giving the eyelid form and support. The aponeurosis of the levator palpebrae superioris is attached to the tarsal plate of the superior eyelid
Tarsal plate
A gelatinous membrane projecting over and in contact with the hair cells of the spiral organ (organ of Corti) in the cochlear duct
Tectorial membrane
A thin, semitransparent partition of fibrous connective tissue between the external auditory meatus and the middle ear
Tympanic membrane or eardrum
The larger of the two divisions of the membranous labyrinth located inside the vestibule of the inner ear, containing a receptor organ for static equilibrium
Utricle
One of the circular projections that is arranged in an inverted V-shaped row at the back of the tongue; the largest of the elevations on the upper surface of the tongue containing taste buds
Vallate papilla or circumvallate papilla
The middle layer of the eyeball, composed of the choroid, ciliar body, and iris
Vascular tunic or uvea
Collective term for the organs of equilibrium, which includes the saccule, utricle, and semicircular ducts
Vestibular apparatus
The membrane that separates the cochlear duct from the scala vestibuli
Vestibular membrane
A small space or cavity at the beginning of a canal, especially the inner ear, larynx, mouth, nose, and vagina
Vestibule
A soft, jellylike substance that fill the vitreous chamber of the eyeball, lying between the lens and the retina
Vitreous body