When Potassium Channels Open and the Ions Diffuse Through the Membrane

Question

When potassium channels open and the ions diffuse through the membrane,
A) the inside of the membrane will become more positive.
B) the inside of the membrane will become more negative.
C) there will be almost no effect on transmembrane potential.
D) the membrane will become depolarized.
E) the membrane will depolarize to threshold.

Accepted Answer

Potassium channels are responsible for the diffusion of potassium ions out of the cell, so when they open, the concentration of positive ions inside the cell decreases. This causes the inside of the membrane to become more negative, leading to hyperpolarization.