In biology the genome of an organism is its whole hereitary information and is encoded in the DNA (or, for some viruses, RNA). This includes both the genes and the non-coding sequences of the DNA. The term was adapted in 1920 by Hans Winkler, Professor of Botany at the University of Hamburg, Germany. The Oxford English Dictionary suggests the name to be a portmanteau of the words gene and chromosome, however, many related -ome words already existed, such as biome and rhizome, forming a vocabulary into which genome fits systematically.