Active transport is broadly categorized based on the source of energy used to drive the movement: Physiology, Active Transport - StatPearls - NCBI Bookshelf
Active transport is a vital biological process where cells move molecules or ions —from an area of lower concentration to an area of higher concentration . Because this movement is "uphill," it requires an input of metabolic energy, typically in the form of Adenosine Triphosphate (ATP) . Core Mechanisms and Types what active transport
The most famous example is the found in animal cell membranes. Active transport is broadly categorized based on the
In biology, cells must constantly move substances across their membranes to maintain life. Some substances move passively, like rolling downhill. However, cells often need to move substances in the opposite direction—from a low concentration to a high concentration. This process is called . Think of it as pushing a ball uphill; it requires energy. In biology, cells must constantly move substances across
| Type | Energy Source | Mechanism | Example | | :--- | :--- | :--- | :--- | | | Direct (ATP) | Uses a pump that directly hydrolyzes ATP to move solutes. | Sodium-Potassium pump, Calcium pump (moves Ca2+ out of cytoplasm). | | Secondary | Indirect (Ion gradient) | Uses the energy stored in an ion gradient (created by primary transport) to drag another molecule along. | Symport (both move same direction) – Sodium-glucose symporter (Na+ flows down its gradient, pulling glucose against its gradient into the cell).