gustation Flashcards
steps of taste perception
tongue > papillae> taste bud > receptor > depolarisation of taste cell > cascade of messages to the brain
type of papillae
filiform
fungiform
circumvallate
foliate
describe filiform papillae
upper surface/ middle line of tongue
- no taste buds
-gripping, textural perception (functional role)
describe fungiform papillae
> 100 on each side
2-4 taste buds each
describe foliate papillae
side of tongue, less of them
several hundred taste buds
describe circumvallate papillae
makes a V shape on back of tongue
7 of them
several hundred tastes on each
what is a taste bud
special sense organ located on tongue and soft palate contains receptors for tase
what % of taste buds are on papillae
75%
where are taste buds found
papillae and soft pallete
when do taste buds develop
7-8 weeks gestation
structurally mature 13-15 weeks
how does taste transduction occur (salt and sour)
complex chemical events
H+ (sour) and Na+ (salt) interact with ion channels
-increase within a cell which depolarizes the membrane and the Ca channel opens, causing release of neurotransmitter
Taste transduction of sweet, umami, bitter
interact with membrane-bound protein (G-protein)
-membrane conductance changes resulting in transmission of the nerve signal at synaptic terminal through the release of neurotransmitters which stimulate the next cell in the sequence
three taste nerves
chorda tympani nerve
glossopharyngeal nerve
vagus nerve
most robust sense?
taste
why might taste be so robust
three nerves innervate THE TONGUE