Osmosis required practical

• What should you be able to describe by the end of the video?

  Investigate the effect of osmosis on plant tissue
• What is osmosis?

  Diffusion of water through a membrane
• What happens to plant cells placed in water?

  Water moves into the cell, causing expansion
• What occurs when a plant cell is placed in a concentrated solution?

  Water moves out, causing cell shrinkage
• What vegetable is commonly used to investigate osmosis?

  Potato
• Why do we peel the potato before the experiment?

  To prevent skin affecting osmosis
• What tool is used to produce potato cylinders?

  Cork board
• What is the ideal length for potato cylinders?

  Approximately three centimeters
• Why is it important to measure the length and mass of potato cylinders?

  To assess the effect of osmosis
• How much of a 0.5 molar sugar solution is added to the first test tube?

  10 centimeters cubed
• Why do we use distilled water instead of tap water?

  Distilled water has no dissolved substances
• What should be done after leaving the potato cylinders overnight?

  Gently roll them on paper towel
• What is the formula to calculate percentage change?

  Percentage change = (change in value / original value) * 100
• If a potato cylinder has a starting mass of 1.56 grams and increases by 0.25 grams, what is the percentage change?

  +16.03%
• If a potato cylinder has a starting mass of 1.32 grams and decreases by 0.19 grams, what is the percentage change?

  -14.39%
• What does the graph of percentage changes in mass or length against sugar concentration show?

  Mass gain in water, loss in concentrated solution
• What does it mean when the graph crosses the x-axis?

  No change in mass occurs
• What concentration indicates no overall osmosis takes place?

  Approximate concentration inside the cell
• What should you learn for the required practical?

  Details of investigating osmosis