07b: Taste and Smell Flashcards
Both taste and smell receptors are stimulated by:
molecules (in solution)
Taste receptors are grouped together as (X), which are found in (Y).
X = taste buds Y = papillae
List the cell types found in one taste bud.
Types I and II: supporting cells (with microvilli)
Type III: sensory receptor
Type IV: basal cell
Basal cells found in taste buds come from (X) and are important for (Y).
X = migration of surrounding epithelium Y = production (via differentiation) into new sensory receptor cells
T/F: there is continual turnover of sensory receptors in taste cells.
True
List taste regions on tongue, from distal to proximal.
- Sweet
- Salty
- Sour
- Bitter
Taste molecules interact with (ion channels/GPCR). All stimuli elicit (increase/decrease) in (X).
Either;
Increase
X = intracellular Ca
Gustducin is a(n) (X) involved in which specific sensations?
X = GPCR
Sweet and bitter(2) tastes
T/F: Gustducin AA sequence and biochemical properties are similar to rod transducin.
True
Salty taste is result of (X) ion, which (depolarizes/hyperpolarizes) taste cells by:
X = Na
Depolarizes;
Passive influx through amiloride-sensitive Na channels
Na entering taste cell does so through (passive/active) transport through (X), located on (apical/basal) surface of cell.
Passive;
X = amiloride-sensitive Na channel
Apical
How is proper Na and (X) ion concentration maintained in taste cell?
X = K
Na/K pump in basolateral membrane
Sour taste is produced by (X). Degree of “sourness” depends on (Y).
X = acids; Y = proton concentration
T/F: Sour(1) and Sour(2) involve similar mechanisms in depolarization of taste cell.
False
Sour(1) mechanism of (depolarization/hyperpolarization).
Depolarization;
Blocks K efflux from cell
Sour(2) mechanism of (depolarization/hyperpolarization).
Depolarization;
Influx through amiloride-sensitive Na channels
List the ion(s) that pass through amiloride-sensitive (X) channels in taste sensation.
X = Na
Na and H
Bitter sensation is mostly elicited by (X). Give an example.
X = poisonous/toxi plant substances;
Quinine or CaCl2
T/F: Bitter(1) and Bitter(2) involve two different GPCR.
False - Bitter(1) doesn’t involve GPCR