Diffusion

• Diffusion= Movement of molecules from a high concentration to a low concentration - passive process- with the concentration gradient
• Active Transport= Movement of molecules from a low concentration to a high concentration against a concentration gradient
• Factors that affect diffusion:

  • Distance of molecule to it's destination (e.g thin membrane)
  • Temperature (affects molecule's kinetic energy)
  • Surface Area (more space)
• Examples of diffusion in humans:

  • Gas exchange in lungs
  • Separate water and nutrients in blood