Why do the Electrolyte concentrations of the plasma and interstitial fluid are very similar while that of ECF and ICF are very different.

Answer 1

Electrolyte concentrations of plasma and interstitial fluid are very similar due to high concentration of sodium, chloride, bicarbonate. Plasma has high concentration of proteins but IF has lower concentration. There is the little difference between them.

ECF and ICF are very different because ECF has higher concentration of sodium and chloride and the ICF has higher concentrations of potassium and phosphate.