We all know that our DNA comes from our parents. Nevertheless, our DNA comes from one more than the other. According to endosymbiosis theory, the mitochondria of eukaryote from aerobic bacterium live in the host cell. Endosymbiosis is a symbiosis of organisms that live inside each other. 1 Millions of years ago, mitochondria were the single-celled, energy producing organelle. Mitochondria and chloroplast resemble bacteria. Each has their own protein synthesis that look like the bacteria and is found in the eukaryotes. They both reproduce like bacteria, and repair their own DNA. Now they generate energy for more compound cells, except still hold their own genomes. Tissues and cells, like our brain, are filled with mitochondria because of its
