Eukaryota

• Main Author: Diana L. Lipscomb
• Format: Reference Entry
• Language: English
• DOI: 10.1036/1097-8542.245250

A taxonomic domain consisting of the vast array of living and fossil organisms with complex cells in which the genetic material is organized into chromosomes [linear pieces of deoxyribonucleic acid (DNA) bound with histone proteins and visible as compact structures during mitosis and meiosis] and contained within a membrane-bound nucleus. Taxonomists recognize three domains of cellular life: Eukaryota, Bacteria, and Archaea. Members of the Eukaryota (or Eukarya, which is sometimes spelled as Eucarya; also formerly referred to as Eukaryotae), commonly known as eukaryotes (see illustration), have a common origin from organisms with prokaryotic cells (Bacteria and Archaea) that do not have their DNA in chromosomes and lack membrane-bound organelles. The eukaryotes thus include all multicellular plants, animals, and fungi, as well as a collection of the unicellular protists (including protozoa). Animal Animal kingdom Archaea Bacteria Cell membrane Cell nucleus Chromosome Fungi Plant Plant kingdom Prokaryote Protista Protozoa