We did a DNA extraction lab of a banana. I was wondering, what exactly is the purpose of using mushed bananas, and how was water used as well (we used the water after using soap and salt, but I can't understand what the water did)? Thanks.
Mush the bananas to release DNA. Water dissolved the DNA (it is an acid).
In the DNA extraction lab of a banana, using mushed bananas serves the purpose of breaking down the cell walls and releasing the contents of the cells. The banana cells contain DNA, which is the genetic material of the organism. By mashing the bananas, you break open the cell membranes and release the contents, including the DNA.
Water is used in the DNA extraction process for a couple of reasons. First, it helps to create a medium in which the chemicals can interact with the banana tissue. When you add water to the mashed bananas, it helps to dissolve and disperse the other substances used in the extraction, such as the soap and salt.
Secondly, water is essential for the solubility of the DNA and the other cellular components. DNA is water-soluble, which means it dissolves in water. When you add water to the mashed bananas, it helps to dissolve the DNA strands, separating them from the other cellular components.
In the DNA extraction process, after adding water to the mashed bananas, you typically add soap. The soap breaks open the cell membranes by dissolving the lipids, which are the major component of cell membranes. This allows the DNA to be released from the cells.
Finally, you add salt to the mixture. Salt is used to help precipitate or separate the DNA from the rest of the cellular debris. When you add salt, it helps to create conditions that cause the DNA to clump together or form a solid, making it easier to collect.
Once the DNA is free from the other cellular materials, you can isolate it further by using various techniques like filtration or centrifugation. These additional steps help to purify the DNA and remove any remaining impurities.
So, in summary, using mushed bananas helps release the DNA from the cells, while water helps to dissolve and separate the DNA from the other cellular components. The soap breaks open the cell membranes, and salt helps to precipitate the DNA, making it easier to isolate.