An inhibitory postsynaptic potential (IPSP) occurs in a membrane made more permeable to ________.
A) K+
B) Na+
C) Ca2+
D) ATP
E) acetylcholine

Question

Quizplus · Accepted Answer

An IPSP is a hyperpolarization of the postsynaptic membrane potential that makes it less likely to reach the threshold for an action potential. This is caused by the opening of channels that allow the movement of positive or negative ions across the membrane. In the case of an IPSP, the channels that open allow the movement of K+ ions out of the cell, or Cl- ions into the cell, making the membrane more negative and less likely to depolarize. Therefore, the best choice for the membrane becoming more permeable is option A, K+.

An Inhibitory Postsynaptic Potential (IPSP) Occurs in a Membrane Made