Mineral Balance & Hydration Flashcards

Which mineral is the main cation in extracellular fluid?

Answer: Sodium

Sodium is the dominant extracellular cation and drives fluid balance outside cells.

Which mineral is the primary cation inside cells?

Answer: Potassium

Potassium is concentrated intracellularly and supports nerve and muscle function.

The sodium-potassium pump moves ions in which pattern?

Answer: 3 Na+ out, 2 K+ in

The ATP-dependent pump ejects three sodium ions and imports two potassium ions per cycle.

A marathon runner drinks large volumes of plain water and develops confusion and nausea. What is the most likely cause?

Answer: Hyponatremia

Excess plain water dilutes blood sodium, causing hyponatremia.

Which mineral is a cofactor in over 300 enzymatic reactions and supports muscle relaxation?

Answer: Magnesium

Magnesium is required for ATP use and many enzyme systems and helps muscles relax.

Which food is among the richest sources of potassium?

Answer: Baked potato with skin

A baked potato with skin supplies far more potassium than the other options.

Which mineral works with sodium to regulate fluid balance and blood pressure?

Answer: Potassium

A higher potassium-to-sodium ratio supports healthy blood pressure and fluid regulation.