It seems like you might be referring to "mitochondria," which are organelles found in the cells of most eukaryotic organisms. Often referred to as the "powerhouses of the cell," mitochondria are responsible for producing adenosine triphosphate (ATP), the main energy currency of the cell, through the process of cellular respiration. They also play roles in other cellular processes such as regulating metabolism, apoptosis, and calcium homeostasis. Mitochondria have their own DNA, which is distinct from the nuclear DNA, and they are thought to have originated from ancient symbiotic bacteria.