This is a complete lesson that can be used to teach your beginning high school biology students about the structure of DNA and the process of DNA replication. As a veteran biology teacher of 42 years, I am well aware that sometimes, a teacher just needs to be absent. The reasons for missing school might be illness, attendance at a conference, a toddler with a fever, having to take care of a furnace that has suddenly stopped working at home, or just a much needed personal day. Who knows!? It happ