Final answer:
The exchange pump referred to is the sodium-potassium pump, which ejects sodium ions from the cell and imports potassium ions, crucial for maintaining the electrochemical gradient and cellular homeostasis.
Step-by-step explanation:
In order to maintain cellular homeostasis, an exchange pump ejects sodium ions from the cell and imports potassium ions. The sodium-potassium pump, also known as Na+/K+ ATPase, is crucial for maintaining the electrochemical gradient in cells, a fundamental aspect of cellular homeostasis. This pump uses energy derived from ATP to transport three sodium ions out of the cell and two potassium ions into the cell during each cycle.
The exchange of a larger number of sodium ions for a smaller number of potassium ions helps create a net negative charge inside the cell, which is essential for various cellular functions including nerve impulse transmission. The carrier protein changes shape and pumps the three sodium ions out of the cell. Then, two potassium ions bind to the carrier protein, and the process is reversed, with the carrier protein pumping the potassium ions into the cell.