Special senses Flashcards
- odor dissolves in mucus surrounding the olfactory cilia (in contact with epithelium in the nasal cavity)
- receptor potential is passed to the olfactory nerves in the olfactory bulb
- impulse passes through olfactory tract into the thalamic and olfactory centers of the brain
sense of smell
receptor potential in taste buds. From chemo receptors called gustatory cells
- propagation of action potential
- transmits to the brain
sense of taste
hearing and balance involve the (3):
- external ear
- middle ear
- inner ear
divisions:
- auricle or pinna: the visible portion of the ear
- external auditory canal (ear canal) tube leading to the temporal bone and tympanic membrane
- tympanic membrane
the external ear
a tiny epthelial cavity hollowed out of the temporal bone
- contains 3 auditory ossicles: malleus, incus, stapes
the middle ear
hammer, attached to inner surface of tympanic membrane
malleus
anvil, attached to malleus and stapes
incus
stirrup, attached to the incus
stapes
consists of a bony labyrinth, and inside the bony labyrinth, a membranous labyrinth
the inner ear
the bony labyrinth consists of 3 parts:
- vestibule
- cochlea
- semicircular canals
the inner labyrinth is inside the bony labyrinth and contains (4):
- utricle and saccule (inside vestibule)
- cochlear duct inside cochlea
- membranous semicircular ducts inside
- the bony semicircular canals
the vestibule and semicircular canals are involved with _____.
balance
the _____ is involved in hearing
cochlea
fluid filling the membranous labyrinth
endolymph
fluid that suspends the membranous labyrinth inside the bony labyrinth
perilymph
sound is created by vibration
- ability to hear sound waves is dependent on volume, pitch, and other acoustic properties
- to be heard, sound must travel through air, bone, and fluid
sense of hearing
sense organs involved with the sense of balance, or equilibrium, are found in the vestibule and semicircular canals
sense of balance
the sense organs located in the vestibule ____ and ____ function in static equilibrium
utricle and saccule
the sense organs associated with semicircular ducts function in ________.
dynamic equilibrium
referes to maintenance of body position (mainly the head) relative to the force of gravity. Stimulated by linear acceleration or deceleration (car or elevator moving)
static equilibrium
maintenance of body position (mainly the head) in response to sudden movements such as rotational acceleration or deceleration
dynamic equilibrium
walls of both organs (utricle and saccule) contain a small thickened region called:
macula
the 2 macula are ____ to each other and provide information for static equilibrium
perpendicular
2 kinds of cells in the macula:
- hair cells
- otolithic membrane
structures in the saccule and utricle of the inner ear, specifically in the vestibular apparatus. Used as gravity, balance, movement, and directional indicators
otoliths
semicircular canals lie at ____ angles to one another in # planes
right angles
3 planes
crista (located in the ampulla) contains ______ and _____.
hair cells, supporting cells
- light converts stored photochmical energy into nervous impulses that are interpreted by the brain as sight
- external structures: eyebrows, eyelashes, eyelids, lacrimal apparatus
- muscles: extrinsic, intrinsic
sense of vision
3 layers of the eyeball:
- fibrous layer (sclera, cornea)
- vascular layer (choroid, ciliary body, iris)
- inner layer (retina, optic nerve, retinal blood vessels)
transparent anterior portion of the fibrous layer
cornea
white opague outer portion of the eye (white secondary to collagen and elastin bundles)
sclera
highly pigmented area
choroid
body formed by thickening of the choroid and contains the ciliary muscle
ciliary body
colored part of the eye that attaches to the ciliary body which controls the diameter of the pupil
iris
mostly made up of nervous tissue with 3 layers of neurons: photoreceptor cells, bipolar cells, ganglion cells
retina
