author : Larry Gonick

This is now a bit dated (it mentions 200,000 genes in the human genome, which is now down to more like 25,000, and there have been various other advances), but it has clear explanations, and is great fun! The descriptions of meitosis and meiosis illustrate the different processes admirably.

It gets a bit heavy and political at the end: the author's "mission", as stated on his website, is "to bring people the information they need to make wise decisions about the future of the human community". Although I'm not sure there's enough information in here to make wise decisions about genetic engineering, it's definitely an excellent place to start.