Chapter 15 Ears & Taste Flashcards
What are chemical senses?
Gustation (taste) and the olfaction (smell)
Taste
To substances dissolved in saliva
Smell
To substances in fluid of the nasal membrane
Nerves responsible for taste
- Facial Nerve VI
- Glossopharyngeal Nerve IX
- Vagus Nerve X
How do chemoreceptors respond to chemicals?
Through aqueous solution
How does smell pass through the body?
Pass through the cribriform plate of the ethmoid bone
What happens after the scent passes through the cribiform plate?
Synapse with the olfactory nerve
What is the organ of smell?
The olfactory epithelium
What does the olfactory epithelium cover
The superior nasal concha
Olfacotry receptor cells are what kind of nerves and what do they radiate with ?
Bipolar neurons that radiate with olfactory cilia
What cushions the olfactory receptors
Supporting cells
What lies at the base of the epithelium
Basal cells
What do cells snypase with olfactory cells
Mitral cells
Glomerular mitral cell’s fuunction
Process odor signals
What 4 parts of the brain does the mitral cells send impulses to
Olfactory cortex, hypothalamus, amygdala, limbic system
How many taste buds are found on the tongue
~10,000
Where are taste buds found?
In the papillae
3 forms of the papillae
Filiform, fungiform, vallate
2 out the 3 papillae that have taste buds
Fungiform and circumvallate papillae
Supporting cells
insulate the receptors
Basal cells
dynamic stem cells
Gustatory cells
Taste cells
5 basic taste sensations
sweet, salt, sour, bitter, umami,
Sweet’s activator
sugar, saccharin, alcohol, and some amino acids
What are the 3 parts of the ear?
External, midde, and internal ear
Function of ceruminous glands
Produce earwax
What is the auricle composed of
The helix (rim) and lobule (earlobe)
What is the typanic membrane (eardrum)?
A thin CT membrane that vibrates in response to sound
What is the middle ear
a small, airfilled, mucosa-lined cavity
Epitympanic recess
superior porrtion of middle ear
Pharyngotympanic tube
connects the middle ear to the nasopharynx
What 3 bones are contained in the typanic cavity?
malleus, incus, stapes
What does the bony labyrinth enclose?
encloses a membranous labrynth
What is the bony labyrinth filled with?
Perilymph
Membranous labyrinth
Serior of mebranous sacs within the bony labyrinth
What is the Membranou labyrinth filled with?
Potassium-rich fluid
What does the membranous labyrinth enclose?
Endolympth
Vestibule
The central egg-shaped cavity of the bony labyrinth
Suspended in the perilympth of the vestibule
saccule & cochlea
Location of maculae
In the vestibule
Receptor for audition
hair cell
Where does the utricle extend into?
semicircular canals
Maculae of the saccules
House equilibrium receptors
Membranous semicurcular ducts
lines the semicircular canals and communicates with the utricle
Ampulla
Swollen end of the semicurcular canals and houses equilibrium receptors
Where do ampullae keep equilibrium receptors?
Crista ampullaris
Equilibrium receptors respond to what?
Angular movements
What do the Corti have?
Has the hair cells that respond to hearing
Where is the organ of Corti held?
In the cochlea
3 chambers of the choclea
Scala vestiubli, cochlear duct, scala tympani
Scalas tympani and vestibuli contain what?
Perilymph
The cochlear duct contains what?
Endolymph
What is the floor of the cochlear duct composed of?
Bony spiral lamina
Basilar membrane
Supports the organ of corti by being the surface for the hair cells
The cochlear branch of the vestibulochlear nerve does what for the organ of Corti.
It connects the organ of Corti to the brain
The stereocilia (hair cells)
Protrude into the endolymph
Touch the tecotrial membrane
Where do impulses from the cochlea go?
pass via the spiral ganglion to the cochlear nuclei
After impulses reach the cochlear nuclei, now what?
Superior olivary nucleus
Inferior colliculus
After an impulse passes through the parts after the cochlear nuclei, what does it reach?
Auditory Cortex
What is pitch perceived by?
The primary auditory cortex and the cochlear nuclei
What is loudness perceived by?
Thresholds of cochlear cells and the # of cells stimulated
What is localization perceived by?
Superior olivary nuclei
Conduction deafness
Sound conduction of the fluids of the inner ear are hampered with
Sensorineural deafness
Damage to the neural structures from the cochlear hair cells to the auditory cortex
Tinnitus
Ringing or clicking of the ears during absence of auditory stimuli
Menirere’s syndrome
labyrinth disorder that affects the cochlea and semicircular canals
Symptoms of Meniere’s syndrome
vertigo, nausea, and vomiting
Vestibular apparatus
equilibrium receptors in the semicurcular canals and vestibule
What are the 3 bony labyrinths and their assigned membraneous labyrinth?
- Semicurcular canals: Semicurcluar ducts
- Vestibule: Utricle and saccule
- Cochlea: Cochlear duct (sacela media)
The 3 bon/membraneous labyrinths’ functions/receptors
- Semicurcular canals: Equalibrium (angular accelaration) / Crista Ampullaris
- Vestibule: Utricle and saccule: Equalibrium (head position relative to gravity, linear acceleration) / Macula
- Cochlea: Cochlear duct (sacela media): Hearing / Spiral Organ
