gel electrophoresis
What is the purpose of adding blue "tracking" dye to the DNA samples?
It makes it easier to load the samples and visually track the migration of DNA through the gel.
What is a restriction map?
It shows where each different restriction enzyme cuts a particular piece of DNA.
How does the process of gel electrophoresis separate DNA fragments?
It uses an electric current to separate different sized molecules of DNA in a porous sponge-like matrix.
Explain why DNA has an overall negative charge.
Phosphate groups in the DNA backbone carry negatively-charged oxygen molecules
Explain how an agarose gel can separate DNA fragments of different lengths.
Smaller fragments move faster, and therefore further, than larger fragments as they snake through the gel.
Why is the fact that DNA has a negative charge so important in the gel electrophoresis process?
So, DNA can be pulled toward the positive field of the gel.
What is the purpose of the agarose gel?
To separate the different sized fragments of DNA.
Why is a marker used when running the fragments through the gel?
it contains DNA fragments of known size. They are run in every gel for comparison with the unknown fragments in other gel lanes.
What is the purpose of ethidium bromide?
it's a dye used by scientists to see where the DNA fragments are located in the gel. It binds to the DNA and glows when illuminated with UV light.
