chap 9 Flashcards
General senses
pain, otuch, pressure, cold, and heat
special senses
taste, smell, vision, hearing, and equilibrium, chemical
sensory adaptation
decline in the rate of impulse formation due o repeated stimulation by the same stimuus
Phasic
Fast adaptation
tonic
slow adaptation
thermoreceptors are sensitive from tempters
beginning at 25C and above 45 C causes extreme burning
cold receptors are senitive to temperatures bellow
20C, while being below 10C triggers cold painful sensation
Mechanoreceptors are sensitive to
mechanical stimuli that displaces the tissue surronding the receptors
Pacinian corpuscles are
pressure receptors deep in the dermis, ligaments,a and tendons.
two types of touch receptorss are
meissner corpuscles and free nerve ending
meissner corpuscles are sensitive to
very light stimuli and are found in demal papillae and hairless portion of the skin
free nerve endings fuction
in touch, itch, temperature, and pain.
free nervve endings are found w
wrapped around hair follicles and are abundant in epithelial and connective tissues and internal organs
proprioceptors
a type of mechanorecetors located in skeletal muscles and tendons.
proprioceptors help
maintain posture, equilibrium, and muscle tone
pain is
receptors of free nerve endings, which is everywhere except for neural tissue in the brain
Pain receptors are
tonic r not at all
referred pain
pain impulses originate from visceral organs but is felt in part of the body wall
reffered pain works because
pain is projected along common nerves used by neurons carrying impulsees from both the body wall and visceral organs
special senses
receptors are localized rather then widely distributed.
chemoreceptors
sensitive to chemicals
Phonoreceptors
sensitive to sound wave vibrations
Photoreceptors
senstitive to light rays
chemoreceptors are located in
taste buds on the tongue (taste cells)
taste hairs
exposed to chemicals on the tongue
four types of taste receptors
Sweet, sour, salty, bitter
olfactory organs are located
in upper portion of nasal cavity
olfactory chemoreceptor cells are supported by
columnar epithelium cells
cilia on distal ends of receptors are
exposed to airborne particles
gaseus chemical must dissolve in fluid covering receptor to
stimulate the receptor
to smell faint ordors the air must be
sniffed
hearing is in a stucture called a
comlex structure
hearing is made u of 3 major parts:
external ear, middle ear, and iner ear.
external ear consist of two parts
aurucle and external auditory canal
auricle
funnel-like structure made of cartilage and skin, attached to side of head
external auditory canal
short tube extending from auricle to eardrum
… and … in the auditory canal kee foriegn particles from reaching the eardrum
Cerumen and hair
the middle ear is composed of 4 components
tympnic membrane, tympanic cavity, auditory tube, ear ossicles
tympanic membrane closes
the inerior to the external auditoy canal
tympanic membrane is externally… and internally…
covered ins kin, covered in mucous membrane
tympanic cavity
air filled pace in temoral bone seperated from external auditory canal by the tympanic membrane
auditory tube
connects tympanic cavity with the pharynx
the auditory tube allows
for air pressure in the tymanic cavity to equal external air pressure
ear ossicles
three tiny bones forming a lever system between tympanic membrane and inner ear
the three bones in the ear ossicles is
malleus, incus, stapes
vibrations form tympanic membrane pass from
malleus to incus to stapes
the inner ear
two series of conduction tubes and chambers embedded, one inside the other
the inner ear consist of the
outer bony labyrinth, and inner membranous labyrinth
space between the to labyrinths in filled with
perilymp
the membranous labyrinth is filled with
endolymph
the inner ear consists of three major parts:
coclea, vestibule, semicircular canals
coclea is
coiled portion
3 chambers seperated b membranes inside the internal ear are,
scala vestibuli, scala tympani, vestibule
the inner ear also includes
oval window, round window
Cochlear duct extends
almost to apex of cochlea
the chochlear duct is separated from the scala vestibuli by the
vestibular membrane
conchlear duct is separated from scala tympani by
basilar membrane
basilar membrane contains
20,000 cross hairs
cross hairs increase in length from
the base of apex of the cochlea
fibers attach to bony center of
conchlea
can vibrate when activated by
vibrations made form sound
organ of corti
is in upper surface of basilar membrane
impulses travel from hair cells along the cochlear branch of
cranial nerve VIII
Low pitch
vibrates longer basilar fibers
high pitch
vibrates shorter basilar fibers
pitch is determined by
portion of basilar membrane and organ of Corti activated by a sound frequency, and the hearing centers receiving the impulses
loudness depends on the
intensity of the vibration of the basilar membrane and organ of corti
greator frequency means
louder sound sensatiosn
severla sensory receptors are involved inequilibrium
proprioceptors, rprotoreceptors, and phonoreceptors
static equilibrium
when the head is motionless
Dynamic equilibrium
when the head is moving
Macula:
the organ of static equilibrium
the macula is inside
the utricle and saccule
otoliths acomplishes two tasks:
increase the weight of gelatinous mass, and mak it more responsive to the force of gravity
semcircular canals contain receptors that detect
motion of the head
canals are oriented at
90 degrees to each other
each ampulla possesses a
crista ampullaris
crista ampullaris is
sensory organ for dynamic equilibrium
crista ampullaris contains
hairs cells with processes extending into a cupula
eyes are the
organ of vision
lacrimal glands
produces tears
lacrimal ducts
carry tears to eye surface
tears drain into the
superior and inferior carnaliculi,
from the canaliculi to the
lacrimal sac
from the lacrimal sac to the
nasolacrimal duct
outer (vascular) layer of eye:
sclera, cornea,
sclera:
tough, fibrous, opaque, white portion of the eye that provides protection for delicate internal portions of the eye and optic nerve
cornea
the antrir, convex, clar window of the eye that bends light rays as they pass through. it
the cornea lacks
blood vessels and nerves
middle layer is made of
chorid coat and ciliary body
the choroid coat
has large blood vessels to nourish the eye, and has melanin to revnt backscattering of light
Ciliary body
has ciliary muscles that surround the lens and suspensory ligaments
the suspensory ligaments are
between ciliary body and lens hold the lens in place
iris is the
colored portion of the eyes that controls the amount of light entering the eye by controlling the size of the pupil
pupil is the
opening in the center of the iris that allows lgiht to pass into the eye
retina
lines the interior of the eye posterior to the ciliary body
rods are for
black and white vision
cones are for
red, yellow, and blue colors
macula
contains the fovea centralis
optical disk
yellowish disc on the retina that is a blind spot
impulses from rod and cones are transmitted to
ganlion neurons
fibers of ganglion neurons converge at optic disc to form the
optic nerve
optic disk lacks photoreceptors and creates
a “blind spot”
anterior cavit
space between cornea and lens which is filled with aqueous humor
the fuction of aqueoous humor is to
maintain cornea shape and regulte internal pressure within the eye
posterior cavity is
located behind the lens and is filled with viteous humor
functions of vitreous humor
presses retina against eye wall and maintains eye shape
retina
lines the interior of the eye posterior to the ciliary body
rods are for
black and white vision
cones are for
red, green, and blue colors
macula
contains the fovea centralis
optical disk
yellowish disc on the retina that is a blind spot
impulses from rod and cones are transmitted to
ganlion neurons
fibers of ganglion neurons converge at optic disc to form the
optic nerve
optic disk lacks photoreceptors and creates
a “blind spot”
anterior cavit
space between cornea and lens which is filled with aqueous humor
the fuction of aqueoous humor is to
maintain cornea shape and regulte internal pressure within the eye
posterior cavity is
located behind the lens and is filled with viteous humor
functions of vitreous humor
presses retina against eye wall and maintains eye shape
anterior cavit
space between cornea and lens which is filled with aqueous humor
the fuction of aqueoous humor is to
maintain cornea shape and regulte internal pressure within the eye
posterior cavity is
located behind the lens and is filled with viteous humor
functions of vitreous humor
presses retina against eye wall and maintains eye shape
cones are most consentrated at the
fovea centralis
rods are least concentrated at the
fovea centralis
the anterior cavity is space between
cornea and lens
the anterior cavity is filled with
aqueous humor
the aqueous humor fuctions to
maintain cornea shae and regulate internal pressure within the eye
the posterior avity is located
behind the lens
the posterior cavity is filled with
vitreous humor
the functions of vitreous humor
it presses retina against eye wall and maintains eye shape
… does the largest refration
cornea
… performs accommondation to provide fine adjustment
lens
presbyopia
having to hold something farther and father away in order to complete acarodation
in nearsightedmess
rays focus in front of retina
in farsightedness
rays focus behind retina
optic chasa
the cross of vision due to the left brain controlling the right, and vice versa.
neural deafness results from
impairment of conchlea or chochlear nerve
conduction deafness results from
impairment of tympanic membrane or ear ossicles.
labyrinthine disease
disorder of inner ear causes range from excess endolymph, infection, allergy, trama, circulation disorder, and aging
motion sickness is a functional disorder produced by
repetitive stimulation of equilibrium receptors by angular or vertial motion
otitis media
pathogens enter the middle ear through the auditory tube that cause paina nd outward bulging of tympanic membrane due to accumulated fluids
astigmatism
unequal fousing of light rays on the retina
blindness
partial or total loss of vision causes by cataracts, deterioration of the retina, damage to optic nerves, and damage to occipital lobes of the brain
cataract
coudiness or opacity of the lens
colorblindness
inability to percieve certain colors or all colors.
glaucoma
aqueous humor is produced more raidly then it is removed, this causes high introcular pressure compresses blood vessels, causing death of receptor cells
strabismus
disorder of extrinsic eye muscles.
