Effects of Osmosis on Plant Tissue

• What is osmosis?

  Osmosis is the diffusion of water from a dilute solution to a concentrated solution through a partially permeable membrane
• What happens to plant cells when they are placed in water?

  Water moves into the cell by osmosis, causing the cell to expand
• What occurs when a plant cell is placed in a concentrated solution?

  Water moves out of the plant cell by osmosis, causing the cell to shrink
• What type of plant tissue is commonly used to investigate osmosis?

  Potato tissue
• Which other vegetables can be used to investigate osmosis besides potato?

  Beetroot and parsnip
• Why do we peel the potato before the experiment?

  Because the potato skin can affect osmosis
• What tool is used to produce cylinders of potato?

  A cork borer
• Why is it important to make all potato cylinders the same diameter?

  To ensure consistent results in the experiment
• What is the recommended length for the potato cylinders?

  About three centimeters
• What happens if shorter cylinders are used in the experiment?

  We might not be able to measure the effect of osmosis
• What measurements are taken before placing the potato cylinders in the solutions?

  The length and mass of each cylinder
• What volume of sugar solution is added to the first test tube?

  10 centimeters cubed of 0.5 molar sugar solution
• What solution is added to the second test tube?

  10 centimeters cubed of 1.25 molar sugar solution
• What is added to the third test tube?

  10 centimeters cubed of distilled water
• Why is distilled water used instead of tap water?

  Because distilled water contains no dissolved substances that could affect osmosis
• How long do we leave the potato cylinders in the solutions?

  Overnight
• What should be done after removing the potato cylinders from the solutions?

  Gently roll them on paper towel to remove surface moisture
• Why is it important not to press on the potato cylinders?

  To avoid forcing water out of the cells
• What measurements are taken after the potato cylinders have been left in the solutions?

  The length and mass of the cylinders are measured again
• What is the formula for calculating percentage change?

  Percentage change = (change in value / original value) * 100
• Why is it important to learn the percentage change formula?

  Because it is not provided in the exam
• If a potato cylinder has a starting mass of 1.56 grams and increases by 0.25 grams, what is the percentage increase?

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

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

  In water, the potato cylinder gains mass, while in concentrated sugar solution, it loses mass
• What does it mean when the graph crosses the x-axis?

  There is no change in mass, indicating equal concentration inside and outside the cell
• What does the concentration where the graph crosses the x-axis represent?

  The approximate concentration inside the cell
• What should students be able to do after watching the video?

  Describe how to investigate the effect of osmosis on plant tissue and calculate percentage change
• What is the importance of osmosis in plant cells?

  It helps maintain turgor pressure, which is essential for plant structure and growth
• What role does the partially permeable membrane play in osmosis?

  It allows water to pass through while restricting the movement of solutes
• How does osmosis affect turgor pressure in plant cells?

  Osmosis increases turgor pressure by allowing water to enter the cells
• Why is using a balance important for measuring mass in the experiment?

  It ensures accurate measurements of the potato cylinders
• Why is it significant to replicate experiments?

  To ensure reliability and accuracy of results
• What is an isotonic solution in relation to osmosis?

  An isotonic solution has the same concentration of solutes as the cell's interior, resulting in no net movement of water
• How does solute concentration impact osmosis?

  Higher solute concentration outside the cell causes water to move out, while lower concentration causes water to move in
• What is the relationship between osmosis and cell health in plants?

  Osmosis is crucial for maintaining cell turgor and overall plant health
• Why are control variables important in the experiment?

  They ensure that the experiment tests only the effect of osmosis