Question

which primary taste does not cause depolarization of the gustatory cell through a g - protein mechanism (secondary messenger system)?
umami
bitter
salty
sweet

Explanation:

• Salty taste is detected by direct movement of \(Na^{+}\) ions into gustatory cells through ion - channels, causing depolarization.
• Umami (glutamate), bitter, and sweet tastes involve G - protein coupled receptors (secondary messenger systems). For example, in the case of sweet taste, the binding of a sweet molecule to a receptor activates a G - protein, which then leads to a series of intracellular events causing depolarization.

Answer:

Salty