Question

In the salamander, the sour taste receptor cells function by having an apically localized K+ channel that is blocked by protons. When protons are applied, what happens to the membrane potential and why?

A. Nothing will happen until the G protein is activated.
B. Receptor hyperpolarization because the H+ ions outside the cell make the inside of the cell more negatively charged
C. Receptor depolarization because K+ permeability, which normally maintains a hyperpolarized resting state, is reduced.
D. Receptor hyperpolarization because H+ ions move into the cell and render it more positively charged.

Answer 1

When protons are applied, the membrane potential of the salamander cells will change. The correct answer is receptor depolarization because K+ permeability is reduced.

Step-by-step explanation:

The sour taste receptor cells in salamanders function by having an apically localized K+ channel that is blocked by protons. When protons are applied, the membrane potential of the cells will change.

The correct answer to your question is option C: Receptor depolarization because K+ permeability, which normally maintains a hyperpolarized resting state, is reduced.

When protons are applied, they block the K+ channel, which reduces K+ permeability. This reduction in K+ permeability disrupts the balance of ions and causes the membrane potential to become less negative or depolarized.