Mastering A&P Neurophysiology Practice Test 2025 – The All-In-One Guide to Exam Success!

The sodium-potassium exchange pump plays a crucial role in maintaining the resting membrane potential of cells by actively transporting sodium and potassium ions across the plasma membrane. This pump operates through active transport, which requires energy in the form of ATP.

In the process, the pump moves sodium ions out of the cell and brings potassium ions into the cell. Specifically, for every three sodium ions that are transported out, two potassium ions are transported in. This movement is essential for various cellular functions, including regulating cell volume, maintaining the electrical excitability of neurons and muscle cells, and facilitating the transport of other substances.

By maintaining the concentration gradients of sodium and potassium, the pump ensures that there is a higher concentration of sodium outside the cell and a higher concentration of potassium inside the cell, which is vital for generating action potentials and overall cellular homeostasis. Therefore, understanding this mechanism is fundamental in neurophysiology, especially in relation to the functioning of neurons.