Now, about 20 to 30 of these cycles can take place within an hour. So we see that after an hour, we can form anywhere from millions to billions of copies of a single DNA segment. So we see that the polymerase chain reaction is very effective and very efficient in actually forming those copies and amplifying the DNA molecule that we're interested in. And one other important property of the polymerase chain reaction is the fact that it takes within a given beaker, within a given closed container. So what that means is after the first cycle takes place, we don't actually have to add anything into that mixture because the mixture has all the ingredients from the beginning. So after one cycle takes place, all we have to do is we have to bump up the temperature back to 95 degrees Celsius to restart cycle number two.