Osmosis

• What is diffusion?

  Net movement of particles from high to low concentration
• How do oxygen and glucose molecules enter a cell?

  By diffusing down their concentration gradient
• What is osmosis?

  Diffusion of water molecules across a membrane
• What is the definition of osmosis?

  Net movement of water from high to low concentration
• What does water concentration refer to?

  Amount of water compared to dissolved solutes
• What are solutes?

  Dissolved molecules like sugars or salts
• How does solute concentration affect water concentration?

  • Higher solute concentration means lower water concentration
  • Lower solute concentration means higher water concentration
• If one beaker has one solute particle and another has three, which has higher solute concentration?

  The beaker with three solute particles
• What determines the concentration of water in a solution?

  The proportion of water compared to solutes
• How does osmosis apply to cells?

  • Water moves from higher to lower water concentration
  • Inside the cell has more solutes than outside
  • Water diffuses into the cell through the membrane
• What is the state of water outside the cell in the example given?

  Almost pure water with few solutes
• What is the process of water moving into the cell called?

  Osmosis
• What role does a partially permeable membrane play in osmosis?

  It allows selective movement of water molecules
• How does the concentration gradient affect osmosis?

  Water moves from high to low concentration gradient