Genome n. [gene plus chromosome] the complete set of chromosomes containing all of the genes of an organism. For man this set of 46 per cell stretches to a 6 foot strand of DNA. Within this string of 3 billion nucleotide bases are 100,000 genes. Utilizing a 4 letter alphabet (Adenine, Guanine, Cytosine, Thymine), genes provide the blueprint for the amino acid sequence of structural protein (cell membrane, connective tissue, etc) or functional protein (hormones, enzymes, transmitters, etc). DNA replication guarantees exact gene copies and chromosome meiosis and crossing over guarantees varied gene combinations. This forms the basis for the similarity and the diversity of all of humankind: the similarity needed to perpetuate successful genes and the diversity needed for genes to respond to the weeding out process of evolution.