Cells that have membrane-bound organelles such as a nucleus are called eukaryotic cells. These cells contain a distinct nucleus enclosed by a membrane that stores genetic material and coordinates cell functions. In addition to the nucleus, eukaryotic cells have other membrane-bound organelles like mitochondria, the Golgi apparatus, endoplasmic reticulum, lysosomes, and chloroplasts (in plants) that perform specialized functions within the cell. Eukaryotic cells are found in organisms classified under the domain Eukarya, including animals, plants, fungi, and protists. In contrast, prokaryotic cells, such as bacteria and archaea, lack a membrane-bound nucleus and other membrane-bound organelles.