Andy, that is a superb question. Thanks. I'd like to tag along with what you have already shared and introduce what Nature Education (1) has on "DNA Is a Structure That Encodes Biological Information":So now the question becomes, "How does DNA encode information?"
1. "Nature Education is a new division of Nature Publishing Group devoted to facilitating high quality, innovative, accessible science education in all countries of the world. Nature Education is currently focused on bringing together high quality content, a global community of faculty, researchers, and students, and technology-based learning tools to provide a new and powerful kind of science learning experience."What do a human, a rose, and a bacterium have in common? Each of these things — along with every other organism on Earth — contains the molecular instructions for life, called deoxyribonucleic acid or DNA. Encoded within this DNA are the directions for traits as diverse as the color of a person's eyes, the scent of a rose, and the way in which bacteria infect a lung cell.
DNA is found in nearly all living cells. However, its exact location within a cell depends on whether that cell possesses a special membrane-bound organelle called a nucleus. Organisms composed of cells that contain nuclei are classified as eukaryotes, whereas organisms composed of cells that lack nuclei are classified as prokaryotes. In eukaryotes, DNA is housed within the nucleus, but in prokaryotes, DNA is located directly within the cellular cytoplasm, as there is no nucleus available.
But what, exactly, is DNA? In short, DNA is a complex molecule that consists of many components, a portion of which are passed from parent organisms to their offspring during the process of reproduction. Although each organism's DNA is unique, all DNA is composed of the same nitrogen-based molecules. So how does DNA differ from organism to organism? It is simply the order in which these smaller molecules are arranged that differs among individuals. In turn, this pattern of arrangement ultimately determines each organism's unique characteristics, thanks to another set of molecules that "read" the pattern and stimulate the chemical and physical processes it calls for.
Please read on . . .