Question

Which statements correctly describe how the sodium-potassium pump works? Select all that apply.

A) Sodium follows its concentration gradient, while potassium is moved against its concentration gradient.
B) ATP provides the energy to operate the motion of the pump.
C) Potassium inside the cell is pumped out while sodium outside the cell is pumped in.
D) The pump transports the two types of ions in different directions.

Answer 1

The sodium-potassium pump uses ATP to move Na+ ions out of the cell and K+ ions into the cell against their concentration gradients, transporting ions in opposite directions to maintain the electrochemical gradient.

Step-by-step explanation:

The sodium-potassium pump is crucial for maintaining the electrochemical gradient across the cell membrane. Here are the correct statements related to its mechanism of action:

• ATP provides the energy to operate the motion of the pump, which is why it is known as an ATPase.
• The pump moves sodium and potassium ions in opposite directions, each against its concentration gradient. Specifically, it moves three Na+ ions out of the cell and two K+ ions into the cell.
• The pump transports the two types of ions in different directions: sodium is moved out of the cell, and potassium is moved into the cell.

The incorrect statement is: Sodium follows its concentration gradient, while potassium is moved against its concentration gradient. In reality, the sodium-potassium pump moves both sodium and potassium against their respective concentration gradients.