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Anatomy Vocab Ch8
Anatomy Vocab Ch8 Marieb
| Question | Answer |
|---|---|
| special senses | smell, taste, sight, hearing; the four traditional senses |
| equilibrium | the fifth sense; receptors housed in the inner ear and called vestibular apparatus; responds to various head movements |
| special sense receptors | large, complex sensory organs (eyes and ears)or localized clusters of receptors (taste buds, olfactory epithelium) |
| accessory structures | extrinsic eye muscles, eyelids, conjuctiva, lacrimal apparatus |
| eyelids | meet at the medial and lateral corners of the eye, the medial and lateral commissure (canthus) |
| palpebral fissure | the space between the eyelids in the open eye |
| tarsal gland | sebaceous glands at the eyelid edge, produce oily secretion that lubricates the eye |
| ciliary gland | modified sweat gland between the eyelashes |
| conjuctiva | delicate membrane lining the eyelids and covering part of the outer surface of the eyeball |
| lacrimal apparatus | lacrimal gland and a number of ducts that drain the lacrimal secretions into nasal cavity |
| lacrimal gland | located above the lateral end of each eye, release tears onto the surface of the eyeball through several small ducts |
| lacrimal canaliculi | tears flush across eyeball and into this first |
| lacrimal sac | second drainage site for tears |
| nasolacrimal duct | third stop for tears as they are flushed across the eyeball; empties into the nasal cavity |
| lysozyme | antibodies contained in lacrimal secretions |
| extrinsic (external) eye muscles | attached to the outer surface of each eye; lateral, medial, superior, inferior rectus and inferior and superior oblique |
| eyeball | hollow sphere composed of three layers (fibrous, vascular,sensory), interior filled with humors that help maintain shape |
| fibrous layer | outermost layer of the eyeball, the protective sclera and cornea |
| sclera | protective, thick, glistening white connective tissue, the white of the eye |
| cornea | the window through which light enters the eye, the most exposed part of the eye, is very vulnerable to damage |
| vascular layer | middle layer of the eyeball; three regions, choroid, ciliary body and iris |
| choroid | posterior region of the vascular layer, blood rich nutritive tunic containing dark pigment that prevents light from scattering inside the eye |
| ciliary body | an extension of the choroid, smooth muscle structure |
| ciliary zonule | suspensory ligament |
| iris | the colored part of the eyeball, houses the pupil |
| pupil | formed by smooth muscle fibers, act as the diaphragm of the camera, regulating the amount of light entering the eyeball |
| sensory layer | innermost layer of the eyeball, containing the retina |
| retina | two layers, pigmented layer, absorbing light and prevents light from scattering inside the eyeball; neural layer contains receptor cells, rods and cones (photoreceptors) |
| photoreceptors | rod and cones of the inner eye |
| vision | electrical signals passing from photoreceptors via bipolar and ganglion cells, leaving the retina via the optic nerve and to the optic cortex |
| optic disc (blind spot) | where the optic nerve leaves the eyeball, light from an object is focused onto the disc causing the object to disappear from view |
| rods | allow us to see gray tones in dim light, allow for peripheral vision |
| cones | allow color under bright light conditions; three types each sensitive to particular wavelengths of light; impulses received at same time from more than one type is interpreted as intermediate color; when all three stimulated we see white |
| fovea contralis | tiny pit that contains only cones, the point of greatest visual acuity or sharpest vision |
| color blindness | lack of cones types cause this, most exclusively in men; is passed thru the genes |
| lens | light entering the eye focuses on the retina by this; divided into two segments, aqueous and vitrous |
| cataracts | vision becomes hazy and distorted eventually causing blindness if not corrected |
| aqueous humor | the front of the lens containing a clear watery fluid |
| vitreous humor | the back of the lens filled with a gel-like substance, prevents the eyeball from collapsing; helps to maintain interocular pressure |
| interocular pressure | the pressure inside the eyeball |
| canal of Schlemm | scleral venous sinus; located at the junction of sclera and cornea; absorption site for aqueous humor into the venous blood |
| glaucoma | intraocular pressure increases to dangerous levels and compresses retina and optic nerve |
| tonometer | measures intraocular pressure |
| ophthalmoscope | illuminates the interior of the eyeball |
| refraction | when light passes from one substance to another that has different density, speed changes and rays are bent |
| accommodation | the ability of the eye to focus for close objects |
| optic nerve | where bundling of axons issue from the back of the eyeball |
| optic chiasma | where fibers from the medial side of each eye cross over to the opposite side of the brain |
| optic tract | fibers synapse with neurons in the thalamus; see optic chiasma |
| optic radiation | axons running to the occipital lobe of brain, carrying the vision message |
| binocular vision | two-eyed vision, provides for depth perception |
| hemianopia | loss of the same side of visual field of both eyes (tunnelvision) |
| eye muscles | both internal and external, controlled by the autonomic nervous system |
| convergence | the reflexive movement of the eyes medially when we view close objects |
| photopupillary reflex | the reaction when eyes are suddenly exposed to bright light, the pupils constrict; prevents bright light from damaging the photoreceptors |
| accomodation pupillary reflex | provides for acute vision, when the pupils constrict when viewing close objects |
| emmetropia | harmonious vision; the eyes focus correctly |
| myopia | nearsightedness |
| hyperopia | farsightedness |
| astigmatism | unequal curvatures in the cornea or lens, causing blurry images |
| receptors | pain, thermo, mechano, chemo, electromagnetic |
| fundus | posterior wall of the eye |
| mechanoreceptors | receptors that respond to physical forces |
| equilibrium receptors | keep nervous system up to date on position and movements of the head |
| ear | divided into 3 area; outer ear, middle ear internal ear |
| hearing areas of the ear | outer and middle ear |
| inner ear | both equilibrium and hearing; bony chambers called osseous (bony) labyrinth, in the temporal bone behind the eye socket |
| outer (external) ear | auricle and external acoustic meatus |
| auricle (pinna) | shell shaped structure surrounding auditory canal of the ear |
| external acoustic meatus | auditory canal; short narrow chamber carved into temporal bone of the skull |
| ceruminous glands | skin lined walls of the external acoustic meatus |
| cerumen (earwax) | waxy yellow secretion, provides sticky trap for foreign bodies and repels insects |
| tympanic membrane (eardrum) | the end of the auditory canal separating the external from the middle ear |
| middle ear (tympanic cavity) | small air-filled mucosa-lined cavity within temporal bone |
| oval and round windows | of the middle ear; help with sound impulses |
| pharyngotympanic (auditory) tube | runs downward to link middle ear cavity with the throat; yawning or swallowing can open it to equalize the pressure in middle ear |
| otitis media | inflammation of the middle ear |
| myringotomy | lancing of the eardrum |
| ossicles | three smallest bones in the body, found in the tympanic cavity; hammer (malleus), anvil (incus), stirrup (stapes) |
| hammer (malleus) | moves with the eardrum, transfering the vibration to the anvil |
| anvil (incus) | passes the vibration from the hammer to the stirrup |
| stirrup (stapes) | presses on the oval window of the inner ear, in response to vibrations passed from the hammer and anvil |
| osseous labyrinth | bony chambers behind the eye socket; 3 parts- cochlea, vestibule and semicircular canals |
| cochlea | spiral, pea-sized part of the bony labyrinth |
| vestibule | between the cochlea and semicircular canal, a cavity |
| perilymph | plasmalike fluid filling the bony labyrinth |
| membranous labyrinth | system of membrane sacs suspended in the perilymph of the bony labyrinth |
| endolymph | thicker fluid of the membranous labyrinth |
| vesibular apparatus | two functional arms; static and dynamic equilibrium, work together for the balance of the body |
| maculae | within the membrane sacs of the vestibule, essential to sense of static equilibrium; report on changes in position of head in relation to pull of gravity when body is at rest; patch of responsive hair cells |
| otolithic hair membrane | hairs are embedded into this macula, jellylike mass studded with otoliths |
| otoliths | tiny stones made of calcium salts |
| vestibular nerves | impulses travel along this, from activation of hair cells telling the cerebellum of the brain that the position of the head has changed |
| dynamic equilibrium | responds to rotary movement of the head, as in twirling or rough seas; receptors are found in semicircular canals; acts jointly with static equilibrium |
| ampula | swollen region at the base of each membranous semicircular canal |
| crista ampullaris | receptor region of the inner ear, base of each semicircular canal |
| cupula | tuft of hair cells covered with gelatinous cap, the receptors on the crista ampullaris |
| vestibular nerve | the sensory nerve from the cupula to the cerebellum, controls and adjusts for the sense of motion |
| static eqiulibrium | balance concerned with the changes of position of the head; works with dynamic equilibrium |
| spiral organ or Cortie | contains hearing receptors or hair cells |
| hair cells | hearing receptors in the spiral organ of Corti |
| basilar membrane | vibrations of the pressure waves set into motion in the inner ear are felt here; high pitched sound effects short hair fibers, low pitched sound effects long hair fibers |
| tectorial memebrane | gel like membrane that lies over the hair cells |
| cochlear nerve | impulses are transmitted along this to the auditory cortex in the temporal lobe |
| adapt | stop responding to stimuli |
| deafness | hearing loss of any degree; conduction (earwax or inflammation) and sensorineural (damage or degeneration) |
| otosclerosis | ruptured eardrum |
| vertigo | the sensation of spinning, causes ringing in the ears, nausea, inability to function |
| Meniere's syndrome | serious pathology of the inner ear, causing vertigo or vertigo symptoms |
| chemoreceptors | receptors for taste and olfaction |
| olfactory receptors | receptors for sense of smell, occupy space the size of a postage stamp on roof of each nasal cavity |
| olfactory receptor cells | neurons eqipped with olfactory hairs, long cilia that protrude from nasal epithelium, bathed in mucous |
| olfactory hairs | cilia that transmit impulses |
| olfactory filaments | bundled axons of olfactory neurons that make up the olfactory nerve |
| olfactory nerve | made up of olfactory filaments, conducts the impulses to the olfactory cortex of the brain; closely tied into the limbic system, the emotional-visceral part of the brain |
| anosmias | olfactory disorders |
| olfactory auras | hallucinations experienced by some epileptics just before going into seizure |
| taste buds | specific receptors for the sense of taste, widely scattered in the oral cavity, 10,000 taste buds, most on the tongue |
| papillae | peglike projections on the tongue |
| circumvallate and fungiform papillae | taste buds are found here, on the tongue |
| gustatory cells | specific cells that respond to chemicals dissolved in the saliva, epithelial cells |
| gustatory hairs | long microvilli of the gustatory cell |
| taste pore | through which the sense of taste is transmitted to the brain |
| taste bud nerves | facial (anterior part of tongue), glossopharyngeal and vagus |
| basal cells | deep in the taste buds, replaced every seven to 10 days |
| taste receptors | sweet, sour, bitter, umami(the flavor of monosodium glutimate), salt |
| strabismus | cross-eyed |
| ophthlmia neonatorum | baby conjunctivitis |
| presbyopia | decreasing lens elasticity accompanying aging |