Diffusion

• Diffusion is the net movement of particles from an area of higher concentration to an area of lower concentration
• Molecules have kinetic energy which means that they'll constantly be moving
• partially permeable:

  • Only some molecules can pass through the membrane
• molecules are able to diffuse into and out of cells:

  • Glucose
  • Water
  • Amino acids
• factors that effect the rate of diffusion:

  • Concentration gradient 
  • Temperature 
  • surface area
  • Distance to diffuse across (if diffusing across a membrane)
• how does higher temperature effect the rate of diffusion:

  • Higher temperature means particles have more (kinetic) energy
  • So they move around faster 
  • And can diffuse more quickly