- An organism that consists of one or more cells with a nucleus and other well-developed compartments. People are eukaryotes. Eukaryotes include all organisms except bacteria, viruses and certain (blue-green) algae which, by contrast, are prokaryotes. See: Prokaryote.
* * *1. A cell containing a membrane-bound nucleus with chromosomes of DNA, RNA, and proteins, mostly large (10–100 μm), with cell division involving a form of mitosis in which mitotic spindles (or some microtubule arrangement) are involved; mitochondria are present, and, in photosynthetic species, plastids are found; undulipodia (cilia or flagella) are of the complex 9+2 organization of tubulin and various proteins. Possession of a e. type of cell characterizes the four kingdoms above the Monera or prokaryote level of complexity : Protoctista, Fungi, Plantae, and Animalia, combined into the superkingdom Eukaryotae. 2. Common name for members of the Eukaryotae. SYN: eucaryote. [eu- + G. karyon, kernel, nut]
* * *eu·kary·ote also eu·cary·ote (')yü-'kar-ē-.ōt, -ē-ət n any of a domain (Eukarya) or a higher taxonomic group (Eukaryota) above the kingdom that includes organisms composed of one or more cells containing visibly evident nuclei and organelles compare PROKARYOTEeu·kary·ot·ic also eu·cary·ot·ic -.kar-ē-'ät-ik adj
* * *eu·kary·ote (u-karґe-ōt) [eu- + karyon] a member of the Eucarya; an organism whose cells have a true nucleus, i.e., one bounded by a nuclear membrane, within which lie the chromosomes and associated proteins and which exhibits mitosis; eukaryotic cells also contain membrane-bound compartments (organelles), in which cellular functions are performed, and have a cytoskeleton that provides mechanical support for the cell. The cells of plants, animals, fungi, and protists are eukaryotic. Cf. prokaryote. eukaryotic adj
Medical dictionary. 2011.