rośliny-i-grzyby: Eukaryote

Evidence: 100 • authority: 72

The eukaryotes () are cellular organisms of the domain Eukaryota or Eukarya, which have a distinct cell nucleus (formed by a nuclear membrane), membrane-bound organelles and organization supported by a cytoskeleton. Extant eukaryotes are traditionally grouped into four kingdoms: animals, plants, fungi and protists. "Protists" are a basal paraphyletic group that includes all algae, amoebae, flagellates and ciliates; however, this is now considered a wastebasket taxon and has been replaced with newer classifications that better represent the phylogeny of these organisms. As part of the prevailing three-domain system, eukaryotes constitute a major group of organisms alongside the two domains o…

Evidence: 59 • authority: 92

Division of labour in a matrix, rather than phagocytosis or endosymbiosis, as a route for the origin of eukaryotic cells.. Two apparently irreconcilable models dominate research into the origin of eukaryotes. In one model, amitochondrial proto-eukaryotes emerged autogenously from the last universal common ancestor of all cells. Proto-eukaryotes subsequently acquired mitochondrial progenitors by the phagocytic capture of bacteria. In the second model, two prokaryotes, probably an archaeon and a bacterial cell, engaged in prokaryotic endosymbiosis, with the species resident within the host becoming the mitochondrial progenitor. Both models have limitations. A search was therefore undertaken f…

Evidence: 47 • authority: 80

The existence of the two domains of life, Bacteria and Archaea, would in itself imply that LUCA and the ancestors of these domains were progenotes

Evidence: 47 • authority: 80

The Existence of the Two Domains of Life, Bacteria and Archaea, Would in Itself Imply that Luca and the Ancestors of These Domains Were Progenotes

Evidence: 36 • authority: 80

Prokaryote/Eukaryote Dichotomy and Bacteria/Archaea/Eukarya Domains: Two Inseparable Concepts

Evidence: 36 • authority: 80

Archaea rather than bacteria control nitrification in two agricultural acidic soils

Evidence: 36 • authority: 92

Timing the origin of eukaryotic cellular complexity with ancient duplications.. Eukaryogenesis is one of the most enigmatic evolutionary transitions, during which simple prokaryotic cells gave rise to complex eukaryotic cells. While evolutionary intermediates are lacking, gene duplications provide information on the order of events by which eukaryotes originated. Here we use a phylogenomics approach to reconstruct successive steps during eukaryogenesis. We find that gene duplications roughly doubled the proto-eukaryotic gene repertoire, with families inherited from the Asgard archaea-related host being duplicated most. By relatively timing events using phylogenetic distances, we inferred th…

Evidence: 36 • authority: 92

Encyclopedia of Family A DNA Polymerases Localized in Organelles: Evolutionary Contribution of Bacteria Including the Proto-Mitochondrion.. DNA polymerases synthesize DNA from deoxyribonucleotides in a semiconservative manner and serve as the core of DNA replication and repair machinery. In eukaryotic cells, there are 2 genome-containing organelles, mitochondria, and plastids, which were derived from an alphaproteobacterium and a cyanobacterium, respectively. Except for rare cases of genome-lacking mitochondria and plastids, both organelles must be served by nucleus-encoded DNA polymerases that localize and work in them to maintain their genomes. The evolution of organellar DNA polymerases…

Evidence: 36 • authority: 72

Marine microorganisms are defined by their habitat as microorganisms living in a marine environment, that is, in the saltwater of a sea or ocean or the brackish water of a coastal estuary. A microorganism (or microbe) is any microscopic living organism or virus, which is invisibly small to the unaided human eye without magnification. Microorganisms are very diverse. They can be single-celled or multicellular and include bacteria, archaea, viruses, and most protozoa, as well as some fungi, algae, and animals, such as rotifers and copepods. Many macroscopic animals and plants have microscopic juvenile stages. Some microbiologists also classify viruses as microorganisms, but others consider th…