Our persuasive speech “DNa can’t tell you everything” is one that will make people think. After all most of us have been reared now on the assumption that DNa can prove whether or not a person is guilty or innocent. This speech speaks of human error and contamination when using DNA, It explains how it was first invented and how much good has been done as a result of the discovery. It tells also of the problems associated with it. It mentions its limitations. Our persuasive speech “DNa can’t tell you everything is very thought provoking. It ends with a poem that sums up our knowledge of DNa in a catchy way.