Electrophoresis

Agarose Gel Electrophoresis A technique used to separate macromolecules like DNA Uses electrical voltage to separate DNA becomes electrically charged in a solution with the correct pH.

Method 1) Sample placed in a well in a gel 3) Electrodes placed at each end of tank 4) Electric voltage applied and runs between electrodes. Particles with a charge move towards the opposite electrode. 2) Buffer solution to keep pH constant.

Method Negative particles move towards the positive electrode -  + Positive particles move towards the negative electrode +  -

Speed of movement The speed at which it travels depends on: How big the charge is (e.g. -1, -2, -3) How large the particle is (smaller moves further)

DNA Profiling Everyone (except identical twins) has unique DNA DNA profiling looks at these differences The DNA being tested is broken into fragments by enzymes and then analysed by electrophoresis Because everyone is different, everyone produces a different pattern of bands.

A B C D E F G

Uses of DNA profiling Forensic Investigations – identifying murderers, rapists, criminals, bodies

Uses of DNA profiling Checking parentage – in people and animals

Uses of DNA profiling Wildlife protection – detecting illegally traded animals

Uses of DNA profiling Testing food – for genetically modified ingredients.