Which mineral moves carbon dioxide, regulates water levels, and transports materials through cell membranes?

Which mineral moves carbon dioxide, regulates water levels, and transports materials through cell membranes?

• A. Sodium
• B. Potassium
• C. Chloride
• D. Phosphorus

Answer: (A)

Sodium is the main extracellular electrolyte that controls water balance and supports transport across cell membranes. Its concentration creates the osmotic pressure that determines where water moves between compartments, helping regulate overall body fluid levels. It also powers membrane transport through the Na+/K+-ATPase pump, which maintains a gradient that enables secondary active transport of nutrients and other substances into cells. Regarding carbon dioxide, most CO2 in the blood is carried as bicarbonate; moving and maintaining this bicarbonate exchange across membranes relies on ion transport processes that depend on the sodium gradient to keep charge balance and allow CO2 to be transported efficiently to the lungs. These combined roles—regulating water, enabling membrane transport, and supporting bicarbonate (CO2) transport—make sodium the mineral that best fits the description.

Sodium is the main extracellular electrolyte that controls water balance and supports transport across cell membranes. Its concentration creates the osmotic pressure that determines where water moves between compartments, helping regulate overall body fluid levels. It also powers membrane transport through the Na+/K+-ATPase pump, which maintains a gradient that enables secondary active transport of nutrients and other substances into cells. Regarding carbon dioxide, most CO2 in the blood is carried as bicarbonate; moving and maintaining this bicarbonate exchange across membranes relies on ion transport processes that depend on the sodium gradient to keep charge balance and allow CO2 to be transported efficiently to the lungs. These combined roles—regulating water, enabling membrane transport, and supporting bicarbonate (CO2) transport—make sodium the mineral that best fits the description.