This is cool. You probably remember from high school biology that DNA copies itself as the first step in cell division. This is how we grow and how we replace lost or damages cells.
The replication process begins when the two strands of our double-stranded DNA “unzip.” That is, they split form one another. Then each stand rebuilds its complementary strand in a complex biological process. This yields two identical strands of double-stranded DNA, each of which becomes the nuclear material for the two identical cells when the division process is completed.
Current DNA analysis mirrors this natural phenomenon. State of the art DNA profiling employs the combination of the Polymerase Chain Reaction and Short Tandem Repeat analysis (PCR-STR). It’s the PCR portion that utilizes this natural process of replication, which is also called “amplification.”
Now it seems someone has used electron microscopy to visualize this process.
DNA Replication RCN.com: http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/D/DNAReplication.html
You Tube: DNA Replication Video: https://www.youtube.com/watch?v=27TxKoFU2Nw
How Stuff Works: DNA Replication: http://science.howstuffworks.com/life/cellular-microscopic/dna3.htm
DNA Forensics: From RFLP to PCR-STR and Beyond: http://www.forensicmag.com/articles/2004/09/dna-forensics-rflp-pcr-str-and-beyond