OS III, Ex II, Taste Flashcards
Where are taste receptor cells found? 4
Tongue surface, soft palate, pharynx and epiglottis
Name the 4 tongue papillae
Filiform, fingiform, circumvillate, foliate
Filiform
no taste buds, they are for touch, pain and temp
Fungiform
anterior pink dots that can contain more than one taste bud
Circumvillate
inverted V near back of tougue
Foliate
side and posterior of tongue, they are located in trenches on side
what is a taste bud?
onion shaped structures with 50-100 taste receptor cells
what does each receptor have to respond to chemicals?
microvili that project through the taste pore so they can respond to chemicals
Original concept of taste?
Sweet, sour, salty, bitter, and umami,
What are the new flavors?
astringency, pungent, fat, starch, metallic
How are receptor cells tuned to taste?
Receptors have microvili that can detect lots of flavors but a majority of them are tuned to just one.
How are the taste regions of the toungue divided
now it?s the region has groups of taste buds tunned moslty to a specific taste
who is morelikly to be a super taster?
women, asians, africans, southamericans.
what causes supertasting?
increased number of fungiform (pink dots) papillae
what two things do molecules interactwith to create taste?
1) ionchannels, 2) membrane receptors that trigger 2nd messenger
what flavors uses ion channels
salty and sour
What flavors use second messenger?
sweet, bitter, umami
What can our perception of multiple tastes come from?
activation of multiple cell types each with different selectivly expressed receptors.
How do taste neuros and smell neurons differ?
smell neurons are specific to certain scents, taste neurons are not specific and can repspond to many different taste, sweet salty etc.
What can modulate taste reception?
local peptices, like Glucagon like peptide (GLP1)
What releases glucagon like peptide?
Taste cells release GLP 1 and its receptor in response to food
What tdoes GLP1 do?
alters responsivity to taste, makes us more sensitive to sweet and less so to umami.
what three cranial nerves play a role in taste?
CN VII - Facial, CN IX - glossopharyngeal, CN X- palate and epiglottis
where to taste neurons project to in medulla?
the solitary nuculeus
Where does taste go after the solitary nucleus?
ipsolaterally (opposite) to thalamus (ventral posteriro medial nucleus)
From the thalamus where does taste go?
to limbic cortex
So path of taste?
Tongue, CN VII, IX,X, to solitary N., thalamus, libic cortex
where is the primay taste cortex?
insula, between temporal and frontal lobe
What does the insula do for taste?
identification and intensity, discrimative aspect of taste
OFC received input from where ?
From the insula about taste and from the piraform cortex and amygdala for smel
What is the OFC, orbitofrontal cortexes role in taste?
appreciation of flavor, reward, feeding corntol, integrates all sensations associated with
What part of brain helps us decide if we are going to eat food or not?
orbitofrontal cortex
