Final answer:
The normal blood potassium level is 3.5 to 5.0 mEq/L, with potassium being essential for cellular function and regulated by mechanisms including the influence of aldosterone.
Step-by-step explanation:
The normal range of potassium (K⁺) in the blood is typically described using concentrations rather than mass per volume. However, based on the information provided, normal levels of potassium in human blood plasma are 3.5 to 5.0 milliequivalents per liter (mEq/L) or roughly equivalent to 14-20 mg/100 ml as mentioned. Potassium is crucial for maintaining cellular function, including the establishment of the resting membrane potential in neurons and muscle fibers. It is primarily an intracellular ion, with concentrations about 30 times higher inside cells than outside. The balance of potassium is maintained through various mechanisms, including the action of aldosterone, which influences potassium exchange with sodium in the renal tubules and is part of the body’s overall regulation of this electrolyte.