1. Tissue is cut into pieces and placed into a cold, isotonic and buffered solution
2. Homogenisation: Tissue is homogenised, for example, in a blender or homogeniser. This releases the organelles from the cell because the plasma membrane is broken down and organelles are released into solution.
3. Filtration: Homogenised suspension (homogenate) is filtered to remove any remaining whole cells or large debris e.g. cell wall or membrane. Organelles are smaller than debris, so pass through
4. Ultracentrifugation: The filtrate is placed in a small tube e.g. test tube, and is centrifuged at a low speed. The higher the speed of the spin, the greater the force.
5. The larger fragments collect at the bottom of the tube in a pellet. Smaller fragments remain suspended in a liquid called the supernatant
6. Supernatant is decanted and re-centrifuged at higher speeds for more force until the desired organelle separates into a pellet
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