Question

The Na⁺/K⁺-ATPase each time transports ________ Na⁺ out of the cell and __________ K⁺ into the cell, resulting in ________ charges inside of the cell?

Answer 1

The Na⁺/K⁺-ATPase transports three Na⁺ ions out and two K⁺ ions into the cell per ATP molecule, contributing to a net negative charge inside the cell and a positive charge outside it.

Step-by-step explanation:

The Na⁺/K⁺-ATPase transports three Na⁺ ions out of the cell and two K⁺ ions into the cell, resulting in more positive charges outside the cell and more negative charges inside it. Each cycle of the pump uses energy from one ATP molecule, removing three positively charged sodium ions and importing two positively charged potassium ions. This differential movement of ions helps establish and maintain the cell's electrochemical gradient, which is necessary for many cellular processes including nerve impulse transmission.

The outside of the cell, therefore, becomes more positively charged than the inside, which remains negatively charged. This is primarily due to the greater number of cations (positive ions) like Na⁺ being expelled than are taken in by the cell, such as K⁺. Additionally, chloride ions (Cl-) tend to accumulate outside the cell, further contributing to this charge difference.