eukaryote(redirected from Eukariont)
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a single- and multiple-celled plant and animal organism in which the body of the cell, in contrast to the cells of a prokaryote, is differentiated into the cytoplasm and the nucleus enclosed by a membrane. The most recent system of the organic kingdom gives the eukaryotes the rank of a superkingdom (including the animal, mushroom, and plant kingdoms) and juxtaposes them to the superkingdom of the prokaryotes.
The genetic material of the nucleus of eukaryotes is organized into chromosomes that are capable of duplication and distribution through mitosis between daughter cells. The molecular basis of the chromosomes is deoxyribonucleic acid (DNA), which is closely associated with histones and other proteins. In most eukaryotes there is a typical sexual process, with the fusion of cell nuclei during fertilization and reduction division during meiosis. The cytoplasm of the cells of eukaryotes, in contrast to that of prokaryote cells, has a complex system of membranes that form an endoplasmotic network, the Golgi apparatus, the mitochondria, and other organoids.