An organelle is a specialized subunit or structure that has a specific function within a cell.
Among the more important cell organelles are the nuclei, which store genetic information; mitochondriaMitochondria are ATP factories. They make most of the ATP in your body, mostly from glucose (sugar) or More, which produce chemical energy; and ribosomes, which assemble proteins.
Reference: NIH National Human Genome Research Institute. (n.d.). Organelle. Accessed 2 Nov 2021.