Monday, February 16, 2015

DNA Strawberry Extraction Lab

We began the extraction of DNA from out strawberries by squishing only the strawberries in the ziploc bag. We then added some buffer solution into the bag and mixed it well. The use of the buffer solution which consists of shampoo broke apart the cell membranes found in strawberries. Soap and shampoo molecules "have both properties of non-polar and polar at opposite ends of the molecule". This forces the polar heads and non-polar inside  of the plasma membrane to disassemble in order to join the shampoo molecules. Without a plasma membrane, the contents of the strawberry cells are released into the mixture. The salt in the buffer will allow the DNA to solidify.  
 Info source: http://www.elmhurst.edu/~chm/vchembook/554soap.html

 We then filtered the contents in the bag so we could capture the DNA molecules.

Alcohol was added to the solution filtered. We poured the alcohol down the side of the test tube so that we could create a separate layer of the alcohol on top of the filtered solution. The addition of alcohol forces the DNA to become like a solid.

 The white, cloudy material at the top of the solution is our strawberry DNA.