ear Flashcards
What is the function of the pinna (auricle)?
It collects sound waves and funnels them into the external auditory meatus.
Where does the external auditory meatus terminate?
At the tympanic membrane (eardrum).
What is the tympanic membrane responsible for?
Converting sound waves traveling in the air into mechanical motion.
What is the function of the ossicles?
They amplify the mechanical motion of the tympanic membrane and transfer it to the inner ear.
What are the three auditory ossicles?
Malleus (hammer), Incus (anvil), and Stapes (stirrup).
What fluid fills the osseous labyrinth?
Perilymph.
What fluid fills the membranous labyrinth?
Endolymph.
What is the cochlear duct filled with?
Endolymph.
What is the role of the Organ of Corti?
It houses hair cells that bend against the tectorial membrane to generate action potentials for hearing.
How is pitch determined in the cochlea?
High pitch activates hair cells near the cochlear base, while low pitch activates those near the apex.
What is the function of the semicircular canals?
To detect rotational movement and maintain dynamic equilibrium.
What are otoliths, and what is their role?
Otoliths are calcium crystals in the otolithic membrane that shift with head movement, bending hair cells to detect linear acceleration.
What is conductive hearing loss?
An inability to transfer sound to the inner ear, often due to damage to the tympanic membrane or ossicles.
What is sensorineural hearing loss?
Hearing loss due to damage to hair cells or the auditory nerve, often treated with cochlear implants.
What is tinnitus?
Phantom ringing in the ears, often caused by nerve damage or irritation.
What is the role of the vestibule?
To detect linear acceleration and head position through the utricle and saccule.
What is the function of the Eustachian tube?
To keep air pressure in the middle ear in equilibrium with the external environment.
What is the vestibular apparatus?
The vestibular apparatus is part of the inner ear that helps detect balance, body position, and movemen
What type of movement do the semicircular canals detect?
The semicircular canals detect dynamic equilibrium, meaning rotational movements of the head or body
What is the crista ampullaris, and where is it located?
The crista ampullaris is a sensory structure located in the semicircular canals that detects rotational movement.
What is the cupula?
The cupula is a gel-like structure covering the hair cells in the crista ampullaris. It bends in response to fluid movement in the semicircular canals, initiating signals for the brain.
How do the semicircular canals detect rotation?
When the head rotates, the endolymph in the semicircular canals moves, pushing the cupula, which bends the hair cells and creates nerve signals.
What type of movements does the vestibule detect?
The vestibule detects static equilibrium (body’s stationary position) and linear movements (e.g., moving forward or up and down)
What are the utricle and saccule, and what do they detect?
Utricle: Detects horizontal movements (e.g., walking forward or sideways).
Saccule: Detects vertical movements (e.g., standing up or riding in an elevator).
What is the macula, and where is it found?
The macula is a sensory structure in the utricle and saccule that detects movement and position by responding to the shifting otolithic membrane
What is the otolithic membrane, and what is its function?
The otolithic membrane is a gel-like structure that covers the macula. It shifts with movement, bending hair cells to signal the brain
What are otoliths, and what is their role?
Otoliths are tiny calcium carbonate crystals embedded in the otolithic membrane. They add weight to the membrane, enhancing sensitivity to movement.
