Active Transport

• Diffusion


  The net movement of particles from an area of higher concentration to an area of lower concentration
• Concentration gradient


  A region with a high concentration and a region with a low concentration
• Active transport


  Moves substances from a more dilute solution to a more concentrated solution, against the concentration gradient, requiring energy from respiration
• Diffusion


  Particles move down the concentration gradient, does not require energy
• Active transport


  Particles are moved against the concentration gradient, requires energy from respiration
• Active transport in animals

  • Cells lining the human small intestine transport sugars from the lumen (lower concentration) into the cell (higher concentration)
• Cells lining the small intestine

  • Have many mitochondria to provide energy for active transport
• Active transport in plants

  • Root hair cells transport ions such as magnesium from the soil (lower concentration) into the cell (higher concentration)
• Root hair cells


  • Have many mitochondria to provide energy for active transport
• Plants need magnesium to make chlorophyll in the leaves
• You can find plenty of questions on active transport in the revision workbook available by clicking the link above