AQA Biology- unit 2: 13.1 Exchange between organisms + their enviroment

  • Created by: sabrina76
  • Created on: 16-03-13 21:41
View mindmap
  • Exchange materials include: respirotary gases, nutrients, excretory products(e.g. urea) and thermal heat
    • Exchange and transport
      • Factors effecting exchange: size of organism, metabolic rate, surface area:volume ratio
      • Specialised exchange surfaces have: very large SA:V ratio,thin and partially permeable exchange surface membrane, a diffusion gradient
      • Exchange takes place by: diffusion and osmosis (passively), or by active transport (actively)
      • Large organism with a small SA:V ratio have adapted by having a flattened shape or specialised exchange surface


No comments have yet been made

Similar Biology resources:

See all Biology resources »See all Ecology, ecosystems and environmental biology resources »