Now, earlier I said that biotechnology can be used in forensic science. For example, let's suppose at some crime scene we find a single follicle of hair. Now, we can extract DNA from that hair follicle and then we can amplify that single DNA strand by using the polymerase chain reaction to produce many of these DNA molecules that we now have at our disposal. And we can take these DNA molecules and we can essentially match them up to the DNA found in individuals in our computer database. And that allows us to basically determine exactly what individual was present at that particular crime scene and that can give us insight into whether or not that individual actually committed the crime. Now, factor number five is if we have a collection of different types of DNA molecules or RNA molecules we can use a specific method or two methods.