The Process of Active Transport (WJEC GCSE Biology): Revision Note

Active Transport

Higher Tier Only

• Active transport can be defined as:

The movement of molecules across a selectively permeable membrane against a concentration gradient

• In active transport molecules move from a region of lower concentration to a region of higher concentration

• The movement of molecules against a concentration gradient requires energy from respiration

  • Respiration produces a molecule called ATP

  • ATP powers the activity of specialised carrier molecules within cell membranes; these carriers act as 'pumps' to move substances against a gradient

Active transport diagram

Active transport is the movement of substances across a cell membrane against a concentration gradient

It requires energy in the form of ATP