In the eukaryote cell nucleus, RNA can be found dispersed in the nuclear fluid, along with DNA, and as the major constituent of the nucleolus. In cytosol (in eukaryotes or in bacteria) RNA molecules can be found free, as structural constituent of ribosomes (organelles specialized in protein synthesis) or even associated to them in the process of production of proteins. Mitochondria and chloroplasts also have their own DNA and RNA.