In the kiwi DNA isolation procedure, what is achieved by adding kiwi pieces to the washing liquid and salt mixture?

• A. DNA is released from the cells into the solution
• B. To sterilize the sample
• C. To precipitate DNA
• D. To remove DNA from the sample

Answer: (A)

The key idea is releasing DNA from the cells into the solution. The detergent in the washing liquid dissolves cell membranes and nuclear envelopes, so when the kiwi tissue is mashed in it, the cells burst and their contents, including DNA, spill into the liquid. The salt helps by neutralizing the DNA’s negative charges and reducing protein–DNA interactions, keeping the DNA in the solution and making it easier to work with in later steps. This stage is about release, not sterilization, precipitation, or removal.