Brett Henson
DNA Assignment
10/23/13
STR is an improvement over PCR because the STR are locations on the chromosome that contain short sequence elements that repeat themselves within the DNA molecule. The strands are significantly shorter than compared to the PCR which means that the STRs are much less susceptible to degradation and are often recovered from bodies or stains that were subject to extreme decomposition. This is an improvement over PCR which is found from blood semen or saliva. Also the longer strands of PCR take a longer time to retrieve a possible answer. The PCR test is considered to be an improvement over the RFLP because of a couple reasons. It takes much less time to complete, a week at most. The test can be performed with a small crime scene sample, which helps investigators who have little physical evidence. The DNA doesn’t have to be recently collected either. The PCR test can still be performed even years or decades after the fact, and still be just as accurate. This is because the PCR method involves copying the available DNA and analyzing only one specific gene. These are all improvements over the RFLP which requires many sample cells from the crime scene. The RFLP needs several strands of hair or large splatters of blood. The cells have to be “fresh”, which means undamaged and recently dead. The test takes anywhere from 3 weeks to three months to complete. Mitochondria are structures within cells that convert the energy from food into a form that cells can use. Each cell contains hundreds to thousands of mitochondria, which are located in the fluid that surrounds the nucleus. Mitochondria are the power plants of the body, providing about 90 percent of the energy that the body needs. Mitochondria DNA testing not been utilized more because of multiple reasons. It is much more rigorous of a testing process. It is more time