What is the principal cation of the ECF?

Question

Quizplus · Accepted Answer

The principal cation of the extracellular fluid (ECF) is sodium (Na+). Option D represents Na+ in its chemical formula, hence it is the correct answer. Option A and E represent calcium (Ca2+) and phosphate (P-) ions respectively, which are not the principal cations in ECF. Option B represents chloride (Cl-) ion, which is an anion, not a cation. Option C represents potassium (K+) ion, which is an important cation in intracellular fluid (ICF), but not the principal cation in ECF.

What Is the Principal Cation of the ECF