Physiology Flashcards
what does frequency of a sound dictate?
pitch (high or low)
what does amplitude of a sound dictate?
intensity- loud or quiet
what does an audiogram result of 0 indicate?
hearing of a healthy 20-year-old male
what range on an audiogram is considered normal?
20-25
describe tonotopic organisation of the cochlea
frequency of sound vibrates different parts of the basilar membrane
what is the pathway of the AP from hair cells to the brainstem?
ECOLI
where is the primary auditory cortex located?
left posterior superior temporal gyrus
two types of hair cells
kinocilium
stereocilia
what are the otolith organs?
utricle
saccule
what do the otolith organs contain?
macules that have stereocilia projecting into a gelatinous matrix with otoconia
four pathways involved in balance sensation
- visual
- cardiovascular
- proprioceptive
- vestibular
two mechanisms involved in balance motor
vestibulospinal tract
vestibulo-ocular reflex
what type of receptors are those for taste and smell?
chemoreceptors
what do taste buds contain?
sensory receptor cells and support cells arranged like orange segments
what replaces taste cell recepters?
basal cells
what do taste cell receptors synapse with?
afferent nerve fibres
four types of taste buds
- filiform
- fungiform
- vallate
- foliate
which type of taste bud does not contain taste buds?
filiform
what are the three cranial nerves that carry taste to the brainstem?
CNVII (chorda tympani)
CNIX (posterior tongue)
CNX (epiglottitis/pharynx)
what are the five primary tastes?
- bitter
- sour
- salt
- sweet
- umami
what produces a bitter taste?
alkaloids
poison
toxic plant derivatives
what produces a sour taste?
free H+ (acids)
what produces a salty taste?
NaCl
what produces a sweet taste?
configuration of glucose
what produces a umami taste?
amino acids
where is the olfactory mucosa located?
roof of the nasal cavity
what is the olfactory mucosa made up of?
receptor cells
supporting cells
basal cells
role of basal cells
secrete mucous and act as precursors
what does each receptor cell look like in the olfactory mucosa?
has a neurone with a thick dendrite and expanded end (olfactory rod)
cilia project from this and odorants binds
why do you need to sniff to smell something?
during normal, quiet breathing odorants do not reach the olfactory mucosa as it is above normal airflow
sniffing enhances the air current upwards
what properties does a substance need to have to be smelled?
volatile enough
sufficiently water soluble
three examples of abnormalities of smell
anosmia
hyposmia
dysosmia
5T’s of referred pain
teeth tongue TMJ throat trigeminal nerve
