- Prokaryote
- Cell lacking a discrete nucleus and other special subcellular compartments. Bacteria and viruses are prokaryotes. Humans are not prokaryotes, but rather eukaryotes.
* * *A member of the superkingdom Prokaryotae; an organismic unit consisting of a single and presumably primitive moneran cell, or a precellular organism, which lacks a nuclear membrane, paired organized chromosomes, a mitotic mechanism for cell division, microtubules, and mitochondria. SEE ALSO: Prokaryotae, Monera, eukaryote. SYN: procaryote.
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pro·kary·ote also pro·cary·ote (')prō-'kar-ē-.ōt n any of the typically unicellular microorganisms that lack a distinct nucleus and membrane-bound organelles and that are classified as a kingdom (Prokaryotae syn. Monera) or into two domains (Bacteria and Archaea) compare EUKARYOTEpro·kary·ot·ic also pro·cary·ot·ic -.kar-ē-'ät-ik adj* * *
pro·kary·ote (pro-karґe-ōt) [pro- + Gr. karyon nut, kernel] any of a group of cellular organisms that lack a true nucleus and nuclear membrane and have nuclear material consisting of a single double-stranded DNA molecule not associated with basic proteins. They lack a cytoskeleton, the cytoplasm is immobile, and organelles are rare. Most have a true cell wall, and all reproduce by cell fission. Organisms are predominantly unicellular but may have filamentous, mycelial, or colonial forms. Prokaryotes are classified into two genetically distinct domains, the Archaea and the Bacteria. Cf. eukaryote. prokaryotic adj
Medical dictionary. 2011.