Osmosis

• What is the aim of this practical?

  to investigate the effect of different sucrose concentrations on the mass of the potato tissue
• What is the method?

  1. Make potato cylinders all the same length
  2. Fill two thirds of each boiling tube with different sucrose solutions
  3. Dry the potato cylinders with a paper towel and then measure and record its mass.
  4. Add them to the different solutions
  5. Remove after 30 minutes. Dry and record the mass
• Hypertonic is when there is a higher solute concentration in the outside of the cell than inside the cell.
• Hypertonic solution causes the cell to shrink.
• An isotonic solution has the same concentration of solutes inside and outside of the cell.
• Isotonic solution does not cause any change in size or shape of the cells.
• A hypotonic solution is a solution that has a lower concentration of solutes compared to the cell.
• A cell in a hypotonic solution will swell.
• What is the independent variable?

  The concentration of sucrose solution
• What is the control variable?

  The length of the potato cylinders, the volume of sucrose solution and the time the potato cylinders are in the solution
• What is the dependent variable?

  The mass of the potato cylinders
• Why are the potatoes dried before weighing them?

  To remove excess solution