Osmosis &rate of osmosis

• osmosis is the diffusion of........?


  water molecules
• what is osmosis?


  The diffusion of water molecules across a partially permeable membrane, from an area of higher water potential to an area of lower water potential
• What is water concentration like in an area of higher water potential?


  higher concentration of water molecules
• What is water concentration like in an area of lower water potential?


  lower concentration of water molecules
• What is WATER POTENTIAL?


  the potential of water molecules to diffuse out of or into a solution
• What has the highest water potential?


  PURE WATER
• What do all solutions have?


  a lower water potential than pure water
• when are 2 solutions isotonic?


  if they have the same water potential
• what does the rate of osmosis depend on?


  • water potential gradient
  • thickness of exchange surface
  • surface area of exchange surface
• why does the rate of osmosis depend on the water potential gradient?


  The higher the water potential gradient, the faster the rate of osmosis
• What happens as osmosis takes place?


  the difference in water potential on either side of the membrane decreases, so the rate of osmosis levels off over time
• why does the rate of osmosis depend on the thickness of the exchange surface?


  the thinner the exchange surface, the faster the rate of osmosis
• why does the rate of osmosis depend on the surface area of the exchange surface?


  the larger the surface area, the faster the rate of osmosis