optional supplemental reading: The pdf below contains a chapter from “The Story of Life” by Sean B. Carroll. This is an easy-to-read description of some of the experiments and discoveries that are the foundation of our modern understanding of DNA as the genetic material. "Who Would Have Guessed It?", focuses on the discovery that living organisms could be transformed, resulting in a different, heritable phenotype (Frederick Griffith) and that the material capable of inducing this transformation was DNA (Oswald Avery, Colin MacLeod and Maclyn McCarty).
