Active transport

Active transport moves substances from a more dilute solution to a more concentrated solution (against a concentration gradient). This requires energy from respiration.

Active transport allows mineral ions to be absorbed into plant root hairs from very dilute solutions in the soil. Plants require ions for healthy growth.

It also allows sugar molecules to be absorbed from lower concentrations in the gut into the blood which has a higher sugar concentration. Sugar molecules are used for cell respiration.

Students should be able to:

• describe how substances are transported into and out of cells by diffusion, osmosis and active transport
• explain the differences between the three processes.

There are links with this content to Cell specialisation.