Diffusion, Osmosis, Active transport

• What is diffusion?


  Diffusion is when particles move from an area of high concentration to an area of low concentration so particles can reach an equilibrium
• Factors that affect diffusion:

  Temperature: More temp increases heat which increases kinetic energy so particles can move faster and diffuse faster.

  Distance:

  Shorter the distance-Faster the rate of diffusion.

  Concentration gradient:

  The greater the difference in concentration between two regions- the faster the rate of diffusion.

  
  

  Size of molecule:

  Larger the molecule: more energy it needs to move so the longer it takes.

  Smaller the molecule: faster the rate of diffusion

  
  

  SA:Volume ratio

  Larger it is, faster rate of diffusion
• What is osmosis?

  Osmosis is the movement of water molecules from an area of lower concentrated solution to an area of higher concentrated solution across a partially permeable membrane.
• Osmosis in Animals:

  If the external solution is more dilute, it will move into animal cells causing them to burst

  If the external solution is more concentrated, excess water will leave the cell causing it to become shrivelled
• Osmosis Plants:

  If the external solution is more dilute, water will move into the cell and into the vacuole, causing it to swell, resulting in pressure called turgor
• Osmosis Plants 2:

  If the external solution is less dilute ,water will move out of the cell and they will become soft. Eventually, the cell membrane will move away from the cell wall and die
• The movement of molecules from a low concentration to a high concentration against their concentration gradient