A common lab practice in 4ESO is the DNA Extraction, before doing it in the laboratory it could be good to check this virtual practice.
In this slide presentation the process of DNA extraction is explained to make you understand its scientific basis:
If you prefer watching a video, you can check this bilingual explanation of the lab practice.
You can get a pdf script and more information from this excellent link:
- Genetic Science Learning Center (2011, January 24) How to Extract DNA from Anything Living. Learn.Genetics. Retrieved February 7, 2011, from http://learn.genetics.utah.edu/content/labs/extraction/howto/index.html
Image by Jokulhaupar
And here by, you have a quick script to do this lab practice (based on this other one)
- Smash your organic sample until you get a soupy mixture. What we are going to want to use is the homogeneous solution in the middle. You probably won’t need all of this but it’s good to have extra just in case.
- Add one tablespoonful of dish washing detergent (or soap) and a pinch of salt (NaCl) to the above solution. Slowly stir this for five minutes.
- Add some drops of pineapple juice (or a pinch meat tenderizer) to the above solution. Again, stir for five minutes.
- Pour and filter enough of the solution into your container to a level of two inches or so. Pour slowly out of the blender so you get the middle layer of solution.
- Drizzle (Tilt the container and pour SLOWLY down the inside of the glass) cold alcohol into the above container. If you do this correctly, a clear layer of alcohol will be floating on top of the denser split pea solution. Add enough alcohol so there is a three inch layer above the split pea solution.
- Now, let the container sit and observe the alcohol layer.