Unknown Child on the Titanic – Part III
Cell with Nuclear and Mitochondrial DNA To understand what happened next, you have to know a little about mitochondrial DNA (mtDNA). Mitochondrial DNA is contained in small, football-shaped inclusions outside the nucleus of a cell. It's widely believed that mitochondria were once independent bacteria that invaded primitive cells millions of years ago. Instead of being digested, these bacteria took up residence in the cell, forming a symbiotic relationship with it. The cell provided them with food and water, and the mitochondria provided the cell with energy for metabolism and heat. The arrangement worked out so well that millennia later, a human cell has up to 1,000 mitochondria, each carrying five to ten copies [...]