Sensory System - Taste Flashcards
1
Q
What is the transduction pathway for salty tasting foods?
A
- Na- influx results directly in a depolarisation of the receptor potential
- depolarisation opens voltage gates Ca2+ channels
- Ca2+ influx and release of neurotransmitters to eh sensory neuron
2
Q
How are sour tasting substances detected?
A
- H+ ions depolarise
- or block K+ leak channels
3
Q
How are bitter tasting substances detected?
A
- sugars activates G protein
- cyclic AMP phosphorylates K+ channels - closes them
- causes depolarisation
4
Q
How are bitter substances detected?
A
- Gq protein GPCR
- IP3 releases Ca2+ from end plastic reticulum
5
Q
What are the classes of taste cells?
A
Type I
Type II
Type III
6
Q
Type I taste cells
A
- transduce salty taste
7
Q
Type II taste receptors
A
- have GPCR for sweet, bitter and umami taste
-
8
Q
Type III taste receptors
A
- detect sour taste
- inhibit type II
9
Q
What is ageusia?
A
Lacking or reduced taste perception
10
Q
What is dysgeusia?
A
Taste distortion
11
Q
What is taste blindness?
A
Inherited inability to sense phenylthiourea (bitter)
