What is primarily maintained by the sodium-potassium pump in cell membranes?

What is primarily maintained by the sodium-potassium pump in cell membranes?

• A. Cellular pH
• B. Membrane potential
• C. Protein synthesis
• D. Ion concentration equilibrium

Answer: (B)

The sodium-potassium pump is critical for establishing and maintaining the membrane potential of cells. This pump actively transports sodium ions out of the cell and potassium ions into the cell, typically moving three sodium ions out for every two potassium ions brought in. This process helps create an electrochemical gradient across the plasma membrane, where the inside of the cell becomes negatively charged relative to the outside. By maintaining a higher concentration of potassium ions inside the cell and a higher concentration of sodium ions outside, the sodium-potassium pump not only contributes to the cell's resting membrane potential but also plays an essential role in the excitability of neurons and muscle cells. Changes in this membrane potential can initiate various physiological responses, such as action potentials in nerve cells, which are critical for neuronal communication and muscle contraction. While the other choices touch upon important physiological processes, they do not accurately reflect the primary function of the sodium-potassium pump. The regulation of cellular pH and ion concentration equilibrium may be influenced by the pump's activity, and protein synthesis is more directly related to ribosomal function and gene expression rather than ion transport. Therefore, maintaining the membrane potential is the most appropriate and direct role of the sodium-potassium pump in cell membranes.

The sodium-potassium pump is critical for establishing and maintaining the membrane potential of cells. This pump actively transports sodium ions out of the cell and potassium ions into the cell, typically moving three sodium ions out for every two potassium ions brought in. This process helps create an electrochemical gradient across the plasma membrane, where the inside of the cell becomes negatively charged relative to the outside.

By maintaining a higher concentration of potassium ions inside the cell and a higher concentration of sodium ions outside, the sodium-potassium pump not only contributes to the cell's resting membrane potential but also plays an essential role in the excitability of neurons and muscle cells. Changes in this membrane potential can initiate various physiological responses, such as action potentials in nerve cells, which are critical for neuronal communication and muscle contraction.

While the other choices touch upon important physiological processes, they do not accurately reflect the primary function of the sodium-potassium pump. The regulation of cellular pH and ion concentration equilibrium may be influenced by the pump's activity, and protein synthesis is more directly related to ribosomal function and gene expression rather than ion transport. Therefore, maintaining the membrane potential is the most appropriate and direct role of the sodium-potassium pump in cell membranes.