The CRISPR, which is a short section of bacterial DNA, and the Cas9 system are tools that edits and manipulates genes in plants and animals. CRISPR is a vital part of immune response in bacteria and fighting off foreign DNA. This system repeats a base set of DNA to replicate a wanted gene.  When bacteria is detected it creates two strands of the same DNA, the enzyme that is produced in this strand is called  Cas9. This cuts out the viral DNA in the strand. Through this process the Cas9 nucleus will not bind with the DNA if the correct sequence isn’t followed, which allows the enzyme to detect if it is dealing with a viral DNA, which reduces the chances of bacteria effecting that specific plant or animal. In going through this process, it stores the current knowledge, allowing the enzyme to better detect the different types of DNA strands for the future.