Final answer:
The intracellular compartment is negatively charged due to the higher concentration of potassium ions and negatively charged proteins, while the extracellular compartment is positively charged, primarily because of higher concentrations of sodium and chloride ions.
Step-by-step explanation:
Generally, the intracellular compartment is negatively charged, while the extracellular compartment is positively charged. This is due to the distribution of ions across cell membranes, where sodium (Na+) ions and chloride (Cl-) ions are concentrated in the extracellular fluid (ECF), and potassium (K+) ions are more concentrated inside cells. The sodium-potassium pump actively maintains this ion distribution by expelling more sodium ions from the cell than the potassium ions it brings in, keeping the intracellular fluid negatively charged.