Diffusion

• Why does a higher temperature increase the rate of diffusion ? 


  Higher temperature leads to particles gaining more kinetic energy . Particles move around more quickly , and can diffuse more quickly
• What is diffusion ?

  The net of movement of particles, from an area of higher concentration, to an area of lower concentration .
• 4 main factors that affect the rate of diffusion across a membrane?

  1. Concentration gradient - larger gradient faster diffusion
  2. Temperature - higher temperature faster diffusion
  3. Surface area - larger surface area faster diffusion
  4. Diffusion distance - larger distance slower diffusion
• Is diffusion an active or passive process ?

  Passive - doesn't require any energy from the cell
• Explain the role of diffusion in gas exchange

  Oxygen diffuses from the alveoli , into the bloodstream

  Carbon dioxide diffuses from the bloodstream , into the alveoli.