Cell Fractionation Flashcards
What happens in cell fractionation
Process where cells are broken up and different organelles are separated
Why do we do cell fractionation
To study the structure and function of isolated organelles
What type of solution is cell fractionation taken place in
Tissue is placed in a cold, buffered solution with the same water potential as the tissue
Why is the solution cold
Reduces enzyme activity that might breakdown the organelle
Why is the solution buffered
- so the ph does not fluctuate
-Changing pH could alter the structure of organelle or affect functioning enzymes
Why does the solution have to have the same water potential
Prevents organelles shrinking or bursting as a result of osmotic loss or gain of water
What is step one of cell fractionation
Cells are broken up by homogeniser releasing organelles
What is step two of cell fractionation
Resultant fluid is filtered to remove complete cells and large debris
What is step three of cell fractionation
Fragments in filtered homogenate are separated by a centrifuge
What happens in step four of cell fractionation
Centrifuge spins tubes of homogenate at high speeds to create centrifugal force
What happens in step five of cell fractionation
-To put a filtrate is placed into centrifuge and span at lower speed
-The heaviest organelle is then force to the bottom, forming a pellet
-The fluid at the top (Suprenatant) Is removed and spun at a higher speed
-The next heaviest pellet then forms
What is the order of organelle size from biggest to smallest?
-nuclei
-mitochondria
-lysosomes
-Endoplasmic reticulum
-ribosomes
