posted by bill on .
I did a DNA fingerprinting lab and I can't understand some of the questions.
1) Different restriction enzymes are isolated from different types of bacteria. What advantage do you think bacteria gain by having restriction enzymes?
2)In your lab, you ran your DNA samples on a 0.8% agarose gel. Would you get the same results if you ran your samples on a higher percentage agarose gel? why or why not?
3)If you have a restriction enzymes that cuts a piece of linear DNA at two recognition sites, how many DNA fragments would you see on a gel?
4)Hind III recognizes a sequence of six nucleotides(AAGCTT) as a cut site. What are the odds that this sequence will occur in a random chain of DNA?
5)predict what would happen if you place your gel in the electrophoresis chamber with the wells containing the DNA nexr to the red(positive) electrode instead of the black(negative)?
Hopefully you will find something here to help you:
2.Depends on what results you're talking about. A higher percentage gel will cause the DNA samples to migrate more slowly but it won't normally change the relative order of the bands in a given lane. Higher percentages can give better separation of small fragments, but large fragments won't separate as well.