Flashcards in Exam 3 Deck (194)
Audible range for humans
20 Hz- 20 kHz
changes in air pressure from a sound wave change in a ______ manner
Main function of outer ear is to
capture sound and rout it to tympanic membrane
Main function of middle ear is
Impedance mismatch -
relative difficulty that sound waves have moving through different media. This problem overcome by different mechanisms
middle ear bones (malleus, incus, stapes)
pressure on tympanic membrane is transferred to smaller surface area of _____
the oval window
organ of corgi consists of the ______ membrane, ______ membrane, nerve cells and stereocilia
what 2 groups of stereo cilia are there?
inner hair cells and outer hair cells
what are the relative shapes of the groups of inner and outer hair cells?
inner hair cells are in a line, outer hair cells are grouped in U shapes
Which hair cells are most important in transducing and sending afferent signals?
inner hair cells
different frequency information conveyed because of maximal displacement variability due to frequency
who discovered tonotopy.
what theory did he propose?
Tonotopic theory of frequency discrimination
fluid that is in direct contact with the hair cells.
Outer hair cells receive signal from the brain – have a motor response and can change their length and alter the properties of the ________. This increases the ___________ of the auditory system.
-frequency discrimination capabilities
Which end of cochlea is most flexible?
High Freq. generate max displacement at the _____, Low Freq max is as _____. This physical map of freq is called Tonotopy
when sound vibrates the basilar membrane, there are 2 phases. In the upward phase, the shear force is towards:
In the downward phase the shear force is towards:
hair cells are highly specialized ______ cells. Their apical surface contains _________, while the basal surface has the ___________
-synaptic end of the cell
Hair cells detect changes in water pressure on _______
Ampullae of Lorenzini –
electrodetectors that are used to detect electric fields in the environment (the head of a hammerhead shark)
What do vestibular hair cells help do and how do they do it?
they are oriented in different ways in a liquid medium to help with balance
what is the really long hair cell in stereocilia bundles?
how are stereocilia in hair bundles oriented?
how does a kinocilium differ from other hair cells?
it contains concentric rings of microtubules
shorter hair cells are connected to longer hair cells via
side to side movement does not depolarize. For hair cells to depolarize, movement in what plane must happen?
in the plane of shortest-longest cells
Mechanoelectrical transduction –
connecting proteins are thought to act as a ‘spring’ and expand/contract upon movement of hair cells. Expansion opens K+ channels
Bundle deflected toward shortest one –
Deflected toward longest one –