Chapter 17 Flashcards
Special Senses are comprised of:
olfaction, gustation, vision, equilibrium and hearing
Olfaction
sense of smell
Olfaction organs
paired; located in the nasal cavity on either side of the nasal septum; consists of olfactory epithelium and lamina propria
Olfactory receptors
dendrites of neurons found in the olfactory epithelium
the knob of the olfactory receptor houses ___ cilia that are exposed to _____.
20
odorants
Basal Cells
regenerative stem cells that replace receptor cells
Olfactory glands
found in lamina purpria; secretions absorb water and form a thick colored mucous
Central adaptation
causes you to lose awareness of certain smells, but allows you to have sensitivities to other smells
Olfaction pathway
an odorant binds to a receptor protein
Lingual papillae
epithelial projections that house the taste buds
filliform papillae
provide friction, no taste buds
fungiform papillae
5 taste buds each
cicumvallate
form v in back of tongue 100 taste buds each
Gustatory Pathway
1.binds to receptor proteins…see notes
there are ___ primary taste sensations: ___ and ____ on the ___ part of the tongue and ___ and ___ on the ____of the tongue
4
sweet and salty, anterior
sour and bitter, posterior
Umami
beef, chicken broth and parmesan cheese due to free glutamates present in circumvallate
____ receptors located primarily in the ___ and affect water balance and blood volume maintenance
water
pharynx
Lacrimal canaliculi
canals that further drain tears to the lacrimal sac
lacrimal sac
receives tears and sends them to the nasolacrimal duct
nasolacrimal canal
passageway in the facial bones that takes tears to the nasal cavity
three layers of the eye
outer fibrous, intermediate vascular and deep inner fibrous: sclera and cornea
sclera
white of eye where intrinsic eye muscles attach
cornea
transparent and avascular; gets nutrients from tears; free nerve ending making it sensitive
(easy transplant, avascular)
Vascular Layer
iris ciliary body and choroid
Iris
contains smooth muscle for pupil diameter changes pigmented and highly vascularized
cilliary body
contains ciliary muscles that attach to and control the shape of lens using suspensory ligaments
choroid
layer between sclera and retina; vascularized and contains melanin
inner layer
retina and optic nerve
retina
pigmented outermost layer and innervated innermost layer, contains photoreceptors that detect light
rods
give us black and white vision for night vision
the lens
focuses the visual image on the photoreceptors
crystallins
transparent proteins responsible for clarity and the focusing power of the lens
cataracts
loss of transparency; can be removed
refractions
the bending of light when it passes from one medium to another medium of a different density
a visual image results from
info from all receptors
light must strike the ___ in precise order to form an image of the object
retina
Greatest amount of refraction occurs as light enters the ___ ?
cornea
a second refractions occurs as light passes from the __ ___ to the ___
aqueous humor
lens
focal point is the specific point of _____ on the ____
intersection
retina
focal distance is the distance between the center of the ___ and the ___ ____
lens
focal point
the closer the object is to the lens the ___ the focal distance
greater
the rounder the lens the more ____occurs which leads to a ____ focal distance; a flat lens leads to a ____ focal distance
refraction
shorter
longer
Accommodation
the automatic adjustment of the eye for clear vision; ciliary muscles adjust the shape of the lens for clarity
astigmatism
is a distortion of an image if light is not refracted properly
colorblindness
dysfuntioning cone
night blindness (nyctalopia)
caused by definciency in bit A. visual pigment reserves decline
depth perception
an interpretation of objects viewed by both eyes that receive slightly different visual images
binocular vision
images from the right and left eye overlap/ the combined vision is binocular vision…these images cross over and are received by the opposite side of the occipital lobe
Inner ear
fluid filled cavity that holds the receptors for both hearing and balance
bony labyrinth
dense bone surrounding membranous labyrinth with perilymph fluid between the two
endolymph
middle air / inner fluid
vestibule
contain membranous sacs called the saccule and utricle
saccule and utricle
both have receptors for gravity and linear excelleration
semicircular canals
contain recptors stimulated by rotation of the head. the fluid within is continuous with the fluid in the vestibule
cochlea
spiral shaped bony chamber that holds the cochlear duct of the membranous labyrinth; receptors here responsible for hearing
round window
free of dense bone, it is a thin membranous partition separation the paralymph of the cochlear chamber from air filled middle chamber
oval window
free of dense bone, connected to base of stapes
equilibrium
vestibule and semicircular canals
semicircular ducts
respond to rotation of head
hair cells
sensory, semicircular ducts, rotational head movements, found in cristae of ampulla and bound to a cupola
stereocilia
short hairs, free surface of ea. hair cell 80-100 per cell
cochlear duct contains
endolymph which lies between a pair of perilymph chambers (scala vestibuli and scala tympani
