In a standard DNA extraction protocol, what is the primary function of the lysis solution?

• A. It specifically binds DNA to a silica column to allow washing and elution
• B. It separates DNA fragments by size through an electric field in a gel matrix
• C. It amplifies specific DNA regions using thermostable DNA polymerase
• D. It disrupts cell and nuclear membranes to release DNA into solution

Answer: (D)

Verified step by step guidance

1. Understand the purpose of each component in a DNA extraction protocol to identify the role of the lysis solution.
2. Recall that the lysis solution is designed to break open cells and nuclei, which involves disrupting the lipid bilayers of cell and nuclear membranes.
3. Recognize that by breaking these membranes, the lysis solution releases the DNA contained within the nucleus into the surrounding solution, making it accessible for further purification.
4. Differentiate this function from other steps in DNA extraction, such as binding DNA to silica columns (which occurs later), gel electrophoresis (used for DNA separation), and PCR amplification (used to amplify DNA sequences).
5. Conclude that the primary function of the lysis solution is to disrupt cell and nuclear membranes to release DNA into solution, enabling subsequent purification steps.