Primary Secondary Active Transport

: This process creates an electrochemical gradient , which stores potential energy. 2. Secondary Active Transport

Active transport is the movement of molecules across a cell membrane against their concentration gradient (from low to high concentration). Because this process fights natural diffusion, it requires (usually ATP) and a specific carrier protein . primary secondary active transport

The substances move in opposite directions. The energy from an ion moving into the cell is used to power the ejection of a different molecule out of the cell. Key Differences at a Glance Primary Active Transport Secondary Active Transport Energy Source Direct chemical energy (ATP) Electrochemical gradient (indirect ATP) Transporter Type Pumping ATPases Cotransporters (Symporters/Antiporters) Relationship Creates the gradient Uses the gradient Examples : This process creates an electrochemical gradient ,

There are two main types: Primary and Secondary Active Transport. Because this process fights natural diffusion, it requires

| Feature | Primary Active Transport | Secondary Active Transport | | :--- | :--- | :--- | | | ATP hydrolysis | Ion gradient (e.g., Na⁺ or H⁺ gradient) | | Indirect Energy Source | None | ATP (used earlier to create the gradient) | | Transport Protein | ATPase pump (e.g., Na⁺/K⁺ pump) | Symporter or Antiporter | | Example | Ca²⁺ pump, H⁺ pump (in mitochondria) | SGLT (glucose), Na⁺/Ca²⁺ exchanger |