Osmosis RP

• What are the three processes that contribute to the movement of substances in and out of cells?

  Diffusion, osmosis, and active transport
• What is the purpose of investigating osmosis in plant tissue?

  To observe the effect of solution concentrations
• What is osmosis?

  Movement of water across a selectively permeable membrane
• How do scientists observe osmosis in cells?

  By using a microscope to view cells in solutions
• What type of tissue is used in the osmosis experiment?

  Potato tissue
• What is the independent variable in the osmosis experiment?

  The concentration of sucrose solutions
• What is the dependent variable in the osmosis experiment?

  The change in mass of potato cylinders
• What is the control variable in the osmosis experiment?

  The time each cylinder is left in solution
• How long should the potato cylinders be left in the sucrose solution?

  40 minutes
• Why should potato cylinders be dried before measuring mass?

  To remove excess liquid for accurate measurement
• What is a mole in terms of concentration?

  Amount of substance per dm³ of solution
• What does a 1.0 mol dm^-3 solution contain?

  One mole of substance per dm³ of solution
• What is cell sap?

  Liquid in the vacuole of plant cells
• What happens to potato cylinders in a hypertonic solution?

  They lose mass due to water loss
• What is plasmolysis in plant cells?

  Vacuole shrinks and membrane pulls away
• How can osmosis be observed in onion skin cells?

  By mounting it in different concentrations of solutions
• What is the purpose of repeating the osmosis experiment?

  To identify and ignore anomalous results
• What safety precautions should be taken during the experiment?

  Wear eye protection and handle tools carefully
• What is the significance of measuring the mass change in potato cylinders?

  It indicates the effect of osmosis on cells
• What are the steps in the osmosis experiment with potato cylinders?

  1. Set up boiling tubes with sucrose solutions.
  2. Prepare and measure potato cylinders.
  3. Place cylinders in solutions for 40 minutes.
  4. Measure and record mass changes.
  5. Repeat for accuracy and analyze results.
• What are the risks associated with the osmosis experiment?

  • Cutting towards oneself with a scalpel
  • Handling chemical solutions without protection
  • Not using a stable surface for cutting