The field of eukaryotic or Eukaryota (from the Greek eu, well and karuon, core) groups, according to the nomenclature of Whittaker, all agencies included in four major realms of the living world: animals, fungi, plants and protists (which should be added according to the nomenclature Chromista Cavalier-Smith, this clade is still challenged by recent studies). They are characterized mainly by cells with a nucleus. They therefore constitute a very broad group of organizations, uni-or multicellular, defined by their cellular structure.

Eukaryotic cells possess, in contrast to prokaryotes (Archaea and Bacteria):

* Organelles, dividing the space into compartments specialized cell, such
o the nucleus (containing DNA),
o mitochondria, endoplasmic reticulum, the Golgi apparatus, ribosomes, peroxisomes, chloroplasts and vacuoles in plants;
* A complex cytoskeleton, composed mainly of actin and myosin;
* The ability to perform endocytosis;
* DNA is divided into several chromosomes;
* Cell division called mitosis (involving centrioles and mitotic spindle);
* A true sexual reproduction, where each mating type makes an equal share of genetic material.

Read also Cell