What you do is you introduce now all the successes in biochemical technologies into this field, and there are two possible... or several possible ones. First of all, we are able nowadays to amplify single molecules. Amplify let's say single RNA or DNA molecules. A Nobel Prize has been given for that discovery. There is the well known PCR method, PCR is an abbreviation for polymerase chain reaction. What is this polymerase chain reaction? Well, you simply mimic nature, and nature polymerises single RNA molecules, and we talked about the stochastic nature of evolutionary theory, from single mutants by an enzyme via a so-called polymerase. Now the trick of the PCR method is that a very special enzyme was chosen, namely an enzyme which can stand high temperatures. It was an enzyme from a thermophile microorganism. This microorganism you find in hot sources on the ground of oceans and so... and you can isolate the enzyme from those organisms here... aquaticus... therefore it's called Taq polymerase, Thermus aquaticus, T-a-q, and this enzyme has its optimum temperature above 70°C.
And now you make the following: you start with your sample which you want to amplify, you add to your system your building blocks for making nucleic acids, you have to make them from the energy-rich triphosphates, and you start with two primers. The primer is a sequence which is complementary to the sequence you want to amplify, and you need two because you need one for the plus strand and one for the minus strand. Now these primers bind at low temperature, so your first stage of the reaction is you're at 40°C. The primers... the two primers bind, one on the plus, one on the minus strand... and then you raise your temperature up to let's say 70°, 75°C, depending on what you are amplifying. Then the region between the two primers will be amplified. You make first two molecules of the one you have there is doubled, then you go up to above 90°C then they would come apart. Now you are back to the first stage, because now to the two molecules, primers will bind. You go to the optimal polymerisation temperature and again to 90°C... in each temperature cycle you double your number of molecules. So after two you have two, then four, then eight, sixteen, we had this before, and after thirty cycles you have 230, which is a billion molecules, and here you have now a macroscopic event.