Active Transport (Cambridge (CIE) AS Biology): Revision Note

The process of active transport

• Active transport is the movement of molecules and ions through a cell membrane from a region of lower concentration to a region of higher concentration using energy from respiration

• Active transport requires carrier proteins (each carrier protein being specific for a particular type of molecule or ion)

• Although facilitated diffusion also uses carrier protein, active transport is different as it requires an input of additional energy

  • The energy is required to make the carrier protein change shape, allowing it to transfer the molecules or ions across the cell membrane

  • The energy required is provided by hydrolysis of ATP (adenosine triphosphate), which is produced during respiration