Electrolytes

Question 1

Cl-

Answer 1

Most prominent anion of the ECF. Kept very low inside cells

Question 1

Na+

Answer 1

Most prominent ECF cation. Makes up a huge fraction of osmolarity of blood plasma and ISF. Kept low inside cells

Question 2

Ca2+

Answer 2

98% stored in bones and teeth. So very low in all 3 compartments!

Question 3

K+

Answer 3

Most prominent intracellular cation. Makes up huge fraction of intracellular osmolarity. Kept very low in ECF

Question 4

HCO3-

Answer 4

Second most prominent anion of ECF. Very important buffer in blood plasma and ISF

Question 5

HPO42-

Answer 5

Most prominent intracellular anion. Kept very low in ECF

Question 6

Mg2+

Answer 6

Second most prominent intracellular cation, though 54% of body stores are in bones