Final answer:
The fluid compartment with high protein and potassium concentration is the intracellular fluid (ICF), which is found within cells and maintained by active transport mechanisms like the sodium-potassium pump.
Step-by-step explanation:
The fluid compartment with high protein and potassium concentration is called the intracellular fluid (ICF). The ICF is the fluid contained within cells, and it is characterized by high concentrations of potassium ions (K+) and proteins. This is distinct from the extracellular fluid (ECF), which includes plasma and interstitial fluid (IF), both having higher concentrations of sodium (Na+) and chloride ions (Cl-). The sodium-potassium pump is an active transport mechanism that helps maintain these ionic concentrations by moving potassium ions into the cell and sodium ions out. This mechanism uses ATP as an energy source to maintain the high level of potassium inside cells, which is essential for many physiological processes.