Question

The principal cation present in the blood plasma is

• A. $K^{+}$
• B. $M{g}^{2+}$
• C. $C{a}^{2+}$
• D. $N{a}^{+}$

Answer 1

The correct option is D $N{a}^{+}$

The plasma is a faint yellow, slightly alkaline, somewhat viscous fluid. It consists of about 90% water, 1% inorganic salts in solution and 7 to 8 % proteins in the colloidal state. The remaining 1% is formed by food materials, waste products, dissolved gases etc. The inorganic salts occur in plasma as ions. Sodium and chloride are the principal cation and anion of the plasma respectively. Thus, the correct answer is option D.