The most critical function of active transport is to create and sustain concentration differences of ions (such as sodium, potassium, calcium, and hydrogen) across the plasma membrane. For example, the sodium-potassium pump (Na⁺/K⁺ ATPase) actively pumps three sodium ions out of the cell and two potassium ions into the cell. This generates:
The gradients established by primary active transport serve as batteries to power secondary active transport . Here, the energy stored in an ion gradient (e.g., sodium ions wanting to flow back into the cell) is harnessed to transport another substance against its gradient. This occurs through: active transport function
2️⃣ This is the rockstar of active transport. The most critical function of active transport is