Osmosis

• What is the process of osmosis?

  Diffusion of water across a membrane
• What is the water potential of pure water?

  Zero
• How does water potential affect osmosis?

  Water moves from higher to lower water potential
• What happens to water potential when solutes are added?

  It becomes negative
• What are isotonic solutions?

  Solutions with the same water potential
• What occurs when a cell is placed in a hypotonic solution?

  The cell swells as water enters
• What happens to a cell in a hypertonic solution?

  The cell shrinks as water exits
• What factors affect the rate of osmosis?

  Water potential gradient, surface area, thickness
• How does the water potential gradient affect osmosis?

  A higher gradient increases the rate of osmosis
• How does the thickness of the exchange surface affect osmosis?

  A thinner surface increases the rate of osmosis
• How does surface area influence the rate of osmosis?

  A larger surface area increases the rate of osmosis
• What are the steps to investigate water potential using potato cylinders?

  1. Make serial dilutions of solutions.
  2. Test potato cylinders in these solutions.
  3. Measure changes in mass or length.
• What is a serial dilution?

  • A technique to create solutions of decreasing concentration.
  • Each solution is diluted by the same factor.
  • Useful for preparing weak solutions.
• How do you create a 1 M sucrose solution from a 2 M solution?

  Add 5 cm³ of 2 M to 5 cm³ water
• What is the final concentration after three serial dilutions starting from 2 M?

  0.125 M
• What precautions should be taken before conducting an osmosis experiment?

  • Conduct a risk assessment.
  • Identify potential hazards.
  • Ensure safety measures are in place.
• What is the purpose of making serial dilutions in experiments?

  To create solutions of known concentrations
• Why is it important to understand the process of making serial dilutions?

  It's necessary for required practicals