Chapter 8: Special Senses Flashcards
What is the meibomian glands
Modified sebaceous glands produce an oily secretion to lubricate the eye
What is the function of the ciliary glands
modified sweat glands between the eyelashes
what is the conjunctiva
membrane that lines the eyelids, connects to the surface of the eye, SECRETES MUCUS TO LUBRICATE THE EYE
what does the lacrimal apparatus contain
lacrimal gland, canals, sac, and nasolacrimal duct
What is the lacrimal gland
produces lacrimal fluid
What is the lacrimal canals
Drains lacrimal fluid from the eyes
what is the lacrimal sac
Provides passage of lacrimal fluid towards nasal cavity
what is the nasolacrimal duct
empties lacrimal fluid into the nasal cavity
what is the function of the lacrimal apparatus
protects, moistens, and lubricates the eye
What are the 3 tunics of the eyes
Fibrous tunic, choroid, and sensory tunic
What layer is the fibrous tunic (sclera)
outside layer
What layer is the choroid
Middle Layer
What layer is the sensory tunic
the inside layer
What is the sclera
white connective tissue layer (white of the eye)
What is the function of the cornea? What does it cover?
Allows for light to pass through it, covers iris and pupil
What is the ciliary body
smooth muscle to which the lens is attached
what is the iris
pigmented layer that gives eye color
what is the pupil
rounded opening in the iris for light to enter
what is the characteristic of the choroid layer
blood rich nutritive tunic
What are the receptor cells found in the sensory tunic
rods and cones
What are the characteristics of rods
found towards the edges of the retina, allows dim light vision and peripheral vision, perception in all gray tones
What are the characteristics of cones
Allow for detailed color vision in bight light
are there photoreceptor cells at the optic disc
no
what is the fovea centralis
area of the retina with only cones - lateral to each blind spot
What is the result of a lacking cone type
color blindness
What is the aqueous humor
watery fluid found in chamber between the lense and cornea, provides nutrients for the lens and cornea, similar to blood plasma
what is the vitreous humor
Keeps the eye from collapsing inward, lasts a lifetime
cateracts
hard forms over the lens
lens accommodation
eye focuses (done by lenses), change shape to focus for closer objects
What are the two major functions of the ear
to hear and balance
What is the most important receptor
mechanical receptors
what are the 3 parts of the ear
outer (external) ear, middle ear, Inner (internal)
What are the outer and middle ear’s only function
hearing
what 2 things are the inner ear responsible for
hearing and balance
What are the 2 parts of the outer ear
Pinna (auricle) and external auditory canal
Why is the pinna important
the physical ear, allows for the sound to go into the ear
What is the technical term for earwax
cerumen
What is the function of the ceruminous gland
secrete earwax
what is the external auditory canal line with
skin
What are the 3 middle ear bones
Malleus (hammer), incus (anvil), Stupes (stirrup)
What is the cochlea responsible for
hearing
what are the vestibule and semicircle canals responsible for
Balance
What is static equilibrium
report on the position of the head with respect to gravity - determines up and down
What is the osseous filled with plasma-like fluid
perilymph
What is inside membranous labyrinth that contains a thicker fluid
endolymph
Where is the organ of corti
in the cochlea
What is the function of hair cells and why are they hairs
hearing receptors and they increase surface area
What are otoliths
tiny stones, float in a gel around hair cells
what is the crista ampullaris
receptors in the semicircular canals
what is the cupula
gelatinous cap that covers hair cells
what is dynamic equilibrium
receptors that respond to angular/rotatory movements of the head
