In this experiment, the DNA from split peas (the seeds of the Pisum sativum plant) will be extracted and examined through a series of steps. DNA is housed in the nucleus of a cell, which is found inside the outer cell membrane; see Figure 4. In the first step, the cells are separated by breaking/cracking the seeds open. Next, the cell membrane and nucleus are lysed or broken down to release the DNA which will be accomplished with a household detergent. Next, an enzyme, called papain powder, is added to separate and isolate the DNA from its surrounding proteins. As the DNA is separated from its surrounding proteins, a salt agent is added to clump the DNA together. Finally, the clumpy DNA is precipitated in an alcohol solution. DNA is insoluble (does not dissolve) in alcohol. Thus, by adding alcohol to the DNA mixture, the DNA will precipitate out of the solution, becoming visible to the naked eye. Although alcohol is used to precipitate the DNA, it also degrades the DNA molecules. The colder the alcohol, the slower it will degrade. Likewise, the warmer the alcohol, the faster the enzymes will begin to break down and degrade the DNA.
1. What was the purpose of adding the detergent to the experiment? If the detergent was not used, do you think the experiment results would have changed? Explain your answer
2. If you used 5% isopropyl alcohol instead of 91%, do you think the experiment results would have changed? Explain your reasoning.