Which of the following is the major positive ion outside cells?

A) nitrogen

B) hydrogen

C) potassium

D) sodium

Answer;

D. Sodium Ions

Explanation; Ions play important and variety of roles in cellular activities. The composition of the cell interior is markedly different from the outside environment of the cell. The dominant positive ion within the cell is potassium with a concentration that is more than 10-fold higher than that of sodium. Outside the cell the major positive ion reverses with sodium as the dominant positive ion.