Fibrоblаsts in skin cаn be cоnsidered precursоr cells becаuse they undergo cell division. These fibroblasts can be converted into "induced pluripotent stem" (iPS) cells by adding 3 specific transcription regulators. Answer these two questions: 1) How are the IPS cells different from the original fibroblasts, and 2) What is one advantage of using these iPS cells to treat diseases rather than procuring stem cells from other sources, such as ES cells or umbilical cord cells?