Gel Electrophoresis: This technique is used to separate fragments of DNA according to their size – longer fragments with a large number of base pairs travel more slowly through the substrate (agarose gel), while shorter fragments with a smaller number of base pairs travel a greater distance. A buffer solution is added to the apparatus and DNA fragments are ‘cut’ at specific sites using restriction enzymes and loaded, together with a fluorescent dye, in ‘wells’ at the negative end of the apparatus. An electric charge is applied and the negatively charged DNA fragments are attracted to the positive end of the gel matrix. Gel Electrophoresis on YouTube.
DNA amplification: Using a Polymerase Chain Reaction (PCR) researchers can create many copies of DNA in a test tube.
DNA profiling: Also called DNA fingerprinting, this technique compares DNA from victims, suspects and crime scenes to determine which samples have the most in common. How does DNA fingerprinting work from the Naked Science Scrapbook (YouTube).
DNA recombination: Scientists are able to insert fragments of DNA from one organism into another organism, bringing together genetic material from various sources. Recombinant DNA produces genetically modified organisms, that may add desirable characteristics to food crops, for example.
- Genetic Engineering from MIT on YouTube
- Steps in Recombinant DNA technology on YouTube
- Mechanism of Recombination from the DNA Learning Centre (YouTube) Steps in
- Recombinant DNA technology from biologyexams4u (YouTube)
DNA sequencing: DNA sequencing is the process of determining the precise order of nucleotides within a DNA molecule. DNA Sequencing on YouTube.
Gene cloning: Molecular cloning is a set of experimental methods in molecular biology that are used to assemble recombinant DNA molecules and to direct their replication within host organisms. Gene cloning in plain English on YouTube.
Gene transformation: “In molecular biology, transformation is the genetic alteration of a cell resulting from the direct uptake, incorporation and expression of exogenous genetic material (exogenous DNA) from its surrounding and taken up through the cell membrane.” Bacterial transformation by zabaaz on YouTube.