3.8 DNA extraction

Question 1

Describe the procedure to extract DNA.

Answer 1

1. Grind sample in mortar and pestle - this breaks down cell walls
2. Mix sample with detergent - this breaks down the cell membrane, releasing the cell contents into solution
3. Add salt - this breaks H bonds between DNA and water molecules
4. Add protease enzyme - This breaks down proteins associated with DNA in the nuclei
5. Add a layer of alcohol (ethanol) on top of the sample - alcohol causes DNA to precipitate out of solution
6. DNA will be seen as white strands forming between the sample and ethanol layer. The DNA can be picked up with a glass rod