electrophoresis. a process that is used to sort fragments of dna by placing the digested dna in a...
TRANSCRIPT
Electrophoresis
ElectrophoresisA process that is used to sort fragments of
DNA by placing the digested DNA in a special gel and adding electricity.
PCR = Polymerase Chain Reaction = Making copies of DNA molecule
Need 1. Primers – Small piece of DNA to start the reaction,
2. DNA Polymerase- Builds a new DNA molecule. Uses a bacteria called Thermus that lives in hot springs at 162 degrees F.
3. Nucleotides A, T, C, G
Thermocycler
Virtual Lab:
University of Utah
Restriction Enzymes
Special protein molecules that are able to cut the DNA at very precise locations
These cut pieces of DNA can be used for:
Electrophoresis - A process for studying gene patterns or similarities
Recombination - Splicing a piece of DNA from one organism into another.
First the DNA is cut into pieces using
Restriction Enzyme Video
Restriction Enzymes were discovered in bacteria in the 1960s. In bacteria they act as their immune system
destroying the viral DNA.
When a virus called a bacteriophage infects a bacteria the Restriction Enzyme cuts up the viral DNA so it can’t hurt
the cell.
The enzyme looks for a specific sequence of nucleotides to attach to and then cuts the DNA at that location. It will cut a piece of DNA as many times as that sequence appears
in the strand so many fragments are produced.
Restriction Enzyme
DNA
DNA is cut into pieces by special chemicals called Restriction Enzymes
Restriction Fragment Length Polymorphism = RFLP
Because the long DNA molecule will be cut a number of times at different locations the result is many different length pieces of DNA are produced these are RFLPs
For the process of Electrophoresis the pieces are loaded into the gel
The pieces of DNA move forming clumps of similar size pieces that look like dark bands
DNA has a negative polarity so is repelled by the negative electrode.
Markers can be mixed with the DNA that show up under UV light to see how far the fragments have moved.
This is a negative image so the bands appear white
Electrophoresis Video
Recombinant DNA – Bacteria Making Insulin
