Exchange materials

• Explain how the surface area to volume ratio affects the way it exchanges materials with the environment

  A larger organism will have a smaller surface area to volume ratio so finds it more difficult to exchange materials quickly
• Effectiveness of an exchange material can be increased by

  • A larger surface area
  • Good blood supply
  • Thin membrane or being thin
  • Being ventalized
• How are villi adapted for absorbing nutrients

  • Good blood supply
  • One cell thick walls
  • Larger surface areas due to folds
  • Network of capillaries
• How are the alveoli adapted for gas exchange

  • Network of capillaries offer good blood supply
  • Membrane of the alveoli have:large surface area, is moist, one cell thick
• How are fish gills adapted for gas exchange

  • Made up of socks of filament with:large surface area to increase diffusion, network of capillaries for good blood supply
• How are root hair cells adapted for uptake of water and mineral ions

  • Lots of mitochondria to take in minerals ions by active transport
  • Large surface area-helps efficient absorption