HideShow resource information
How many basic tastes are there?
Six, possibly. Umami, salty, bitter, sour, sweet, fat.
1 of 32
What receptors do sweet tastes transuce through
T1R2+T1R3, Possibly others
2 of 32
What receptors do salty tastes transuce through
ENac receptors
3 of 32
What receptors do bitter tastes transuce through
4 of 32
What receptors do umami tastes transduce through?
T1R1 + T1R3, mGluRs
5 of 32
What receptors do fat tastes transuce through
GPR120, GPR40, CD36, Kch
6 of 32
What modalities are combined for a full sense of taste?
Smell, texture, temperature and taste
7 of 32
What do we use to taste?
Tongue, palate, pharynx, epiglottis.
8 of 32
The three types of papillae. Draw a tongue and label it.
Fungiform, filliform, circumvallate papillae, foilate papillae
9 of 32
Relationship between papillae and taste receptor cells
Each papillae has 1-100 taste buds. Each taste bud has 50-100 taste receptor cells.
10 of 32
Draw a taste receptor cell
microvilli, taste pore, taste cells, basal cells, gustatory afferents.
11 of 32
What is the threshold concentration
The concentration where a single papilla will evoke a sense of taste in response to a purely sweet/sour stimuli.
12 of 32
Are papillae selective for one taste?
At low concentrations, not at high.
13 of 32
What is the chemically selective part of the taste receptor cell?
A small membrane region called the apical end
14 of 32
What is the apical end like?
It has small microvilli that project into the taste pore, where it exposed to the contents of the mouth
15 of 32
What is the life cycle of a taste cell?
Two weeks
16 of 32
Are taste cells neurons? What makes them like neurons?
They aren't, but they form synapses, both with the gustatory afferents and the basal cells
17 of 32
What happens when a taste cell is activated by an appropriate chemical?
it's membrane potential changes, by depolarising. It undergoes a voltage shift called the receptor potiential.
18 of 32
Taste transduction: Salt. Give an overview
Na+ acts on amiloride sensitive calcium channels, causing depolarisation. Depolarisation -> VGNaC and VGCCs to open. ATP is released onto the gustatory afferent
19 of 32
How is the amiloride sensitive Na+ channel different to the VGCC
It's voltage independent and it stays open all the time.
20 of 32
Hydrogen ions enter through amiloride sensative na channels. They also block K+ channels
21 of 32
Bitterness. What receptor?
T2R which is GPCR.
22 of 32
Bitterness- what does the GPCR activate.
PLCB2 which activates IP3 which causes a rise in intracellular calcium.
23 of 32
What does the rise in calcium do
TRPM5 opens and lets sodium in, same with VGSCs. this causes depolarisation and ATP is released
24 of 32
What are the receptors for sweet and umami tastants? Then, how is the pathway different to bitterness?
Sweet - T1R2, T1R3. Umami - T1R1/T1R3
25 of 32
Where is the main flow of taste information from the taste buds?
To the thalamus, then to the cerebral cortex
26 of 32
Cranial nerves and gustation
The anterior two-thirds of the tongue and the palate send axons into a branch of the facial nerve. the posterior third is innervated by the glossopharangeal nerve. Throat, epiglottis and pharynx - vagus nerve
27 of 32
Where do the axons synapse?
The gustatory nucleus, part of the solitary nucleus in the medulla
28 of 32
The path diverges - Explain the path to the neocortex via the thalamus
neurons of the gustatory nucleus synapse on a subset of small neurons in the VPM. The VPM sends axons to the primary gustatory cortex.
29 of 32
Where is the primary gustatory cortex?
Brodmann's area 36, near the insula cortex.
30 of 32
What can lesions in the VMP or the gustatory cortex cause
ageusia - loss of taste perception
31 of 32
What two features allow recognition of taste
roughly labelled lines and population coding - incl. smell, texture.
32 of 32

Other cards in this set

Card 2


What receptors do sweet tastes transuce through


T1R2+T1R3, Possibly others

Card 3


What receptors do salty tastes transuce through


Preview of the front of card 3

Card 4


What receptors do bitter tastes transuce through


Preview of the front of card 4

Card 5


What receptors do umami tastes transduce through?


Preview of the front of card 5
View more cards


No comments have yet been made

Similar Biology resources:

See all Biology resources »See all Taste resources »