* Mitochondria: These are responsible for cellular respiration and energy production. They have their own circular DNA molecule, called mitochondrial DNA (mtDNA), which encodes for some of the proteins involved in mitochondrial function.
* Chloroplasts: These are found in plant cells and are responsible for photosynthesis. They also possess their own circular DNA molecule, called chloroplast DNA (cpDNA), which codes for some of the proteins needed for photosynthesis.
It's important to note that these organelles are thought to have originated from symbiotic bacteria that were incorporated into eukaryotic cells. This is why they have their own DNA, separate from the nuclear DNA.
So, while the nucleus holds the majority of a cell's genetic information, mitochondria and chloroplasts each have their own unique sets of genes that are essential for their specific functions.
