DNA Extraction Lab

Why was it necessary to add a buffer to the spun down cells?

• To dissolve the cell membrane for DNA extraction

• To balance the sample back after lysis

• For resuspension

• All of the above

Investigators can individualize blood evidence by:

• Determining the blood group

• Observing the blood cells

• Comparing the DNA from the cells

• Using the Kastle-Meyer test

Tags

NGSS.HS-LS3-2

Which suspect left the blood stain?

• Bob

• Sue

• John

• Lisa

What is the primary purpose of adding a lysis buffer during DNA extraction?

• To break down the cell membrane and release DNA

• To neutralize the pH of the solution

• To precipitate proteins

• To stain the DNA for visualization

Which of the following is a common method for precipitating DNA from a solution?

• Adding ethanol or isopropanol

• Heating the solution to 100°C

• Using a magnetic stirrer

• Adding hydrochloric acid

In a DNA extraction lab, why is it important to keep the samples cold?

• To prevent DNA degradation by enzymes

• To increase the solubility of DNA

• To enhance the activity of restriction enzymes

• To speed up the lysis process

What role does protease play in the DNA extraction process?

• It breaks down proteins that may contaminate the DNA

• It enhances the binding of DNA to the extraction column

• It stabilizes the DNA structure

• It neutralizes the lysis buffer

Why is it necessary to centrifuge the sample during DNA extraction?

• To separate the DNA from cellular debris

• To dissolve the DNA in the solution

• To increase the temperature of the sample

• To mix the reagents thoroughly

Which of the following is a visual indicator that DNA has been successfully extracted?

• A white, stringy precipitate forms

• The solution turns blue

• Bubbles form in the solution

• The solution becomes clear

What is the function of a chelating agent like EDTA in DNA extraction?

• To bind divalent cations and inhibit DNase activity

• To enhance the solubility of DNA

• To precipitate DNA

• To act as a buffer