Cell fractionation

• What is cell fractionation?

  It is the process of breaking up cells and separating their organelles.
• What is the purpose of centrifugation in cell fractionation?

  To separate organelles based on their different densities.
• What is the order of organelles from heaviest to lightest during centrifugation?

  • Nucleus
  • Chloroplast
  • Mitochondria
  • Lysosome
  • Ribosome
• What are the two stages of cell fractionation?

  1. Homogenisation

  • Break cells open in a homogeniser.
  • Filter the homogenate to remove debris.

  1. Ultracentrifugation

  • Spin the filtrate at increasing speeds to separate organelles.
• What is the purpose of homogenisation in cell fractionation?

  To break cells open and release organelles.
• Why is it important to keep the solution ice-cold during cell fractionation?

  To reduce the activity of enzymes that break down organelles.
• What does an isotonic solution prevent during cell fractionation?

  It prevents water from entering organelles by osmosis and prevents lysis.
• What is the role of buffer solution in cell fractionation?

  It maintains pH so proteins and enzymes are not denatured.