Gustatory System Flashcards
(9 cards)
What are the 5 basic tastes?
Sweet, salty, bitter, umami, sour
How are tastants for the 5 basic tastes translated into membrane potential signals?
Tastant disolved in saliva and interacts with taste receptor cells on taste buds
Activates a taste cell → depolarization → activates pathway
What receptors do each of the 5 tastes use?
Which use GPCRs and which use ion channels?
Also name the specific receptors
Sweet, umami, bitter: GPCRs
* Umami: T1R1 & T1R3
* Sweet: T1R2 & T1R3
* Bitter: T2Rs
Salty, sour: specific ion channels
Why isn’t it a problem that we can’t discriminate well between bitter tastants?
Bitter is meant to cause avoidance
What cranial nerves are involved in the gustatory pathway?
CN VII, IX, X
Why can’t pandas taste umami and why can’t cats tast sweet?
What receptors are involved?
Panda: T1R1 is a pseudogene
Cat: T1R2 is a pseudogene
Experiment to show that the pathway determines behavior but not the tastant or taste receptor
What is the taste pathway?
Tongue → CN VII, IX, X → Brain stem → thalamus → gustatory cortex
What is the mechanism on the tongue?
