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Percolatea
Percolatea are a class of excavates in the phylum Percolozoa. See also * Percolozoa The Percolozoa are a group of colourless, non-photosynthetic Excavata, including many that can transform between amoeboid, flagellate, and cyst stages. Characteristics Most Percolozoa are found as bacterivores in soil, fresh water and occasional ... References Percolozoa Excavata classes {{Excavata-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stephanopogon
''Stephanopogon'' is a genus of flagellated marine protist that superficially resembles a ciliate. Characteristics ''Stephanopogon'' closely resembles certain ciliates and was originally classified with them (, but is now considered related to heterolobosean flagellates. The cell is somewhat flattened, with multiple smooth flagella arranged in rows running from the front to the back, and has an anterior mouth supported by rods. They feed on bacteria, diatoms, and other smaller organisms. There are 2-16 nuclei, but they are not differentiated into macronuclei and micronuclei as occurs in ciliates. They have a cosmopolitan distribution. Classification Because nuclear dimorphism is absent, ''Stephanopogon'' had been regarded as an evolutionary intermediate between the ciliates and other protozoa, and possibly an ancestor of the animals as well. Corliss and Lipscomb showed that it is not cytologically similar to ciliates, lacking their complex pellicle and infraciliature. Fur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Percolozoa
The Percolozoa are a group of colourless, non-photosynthetic Excavata, including many that can transform between amoeboid, flagellate, and cyst stages. Characteristics Most Percolozoa are found as bacterivores in soil, fresh water and occasionally in the ocean. The only member of this group that is infectious to humans is ''Naegleria fowleri'', the causative agent of the often fatal disease amoebic meningitis. The group is closely related to the Euglenozoa, and share with them the unusual characteristic of having mitochondria with discoid cristae. The presence of a ventral feeding groove in the flagellate stage, as well as other features, suggests that they are part of the Excavata group. The amoeboid stage is roughly cylindrical, typically around 20-40 μm in length. They are traditionally considered lobose amoebae, but are not related to the others, and unlike them, do not form true lobose pseudopods. Instead, they advance by eruptive waves, where hemispherical bulges a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Percolomonas
''Percolomonas'' is a genus of free-living flagellate Heteroloboseans, forming a clade with ''Stephanopogon''. The genus includes six described species (see infobox). However, ''P. cosmopolitus'' is likely a species complex containing multiple cryptic species of extremely similar morphology Morphology, from the Greek and meaning "study of shape", may refer to: Disciplines * Morphology (archaeology), study of the shapes or forms of artifacts * Morphology (astronomy), study of the shape of astronomical objects such as nebulae, galaxies ... but significant genetic divergence. References Percolozoa Excavata genera {{Excavata-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Excavata
Excavata is a major supergroup of unicellular organisms belonging to the domain Eukaryota. It was first suggested by Simpson and Patterson in 1999 and introduced by Thomas Cavalier-Smith in 2002 as a formal taxon. It contains a variety of free-living and symbiotic forms, and also includes some important parasites of humans, including ''Giardia'' and ''Trichomonas''. Excavates were formerly considered to be included in the now obsolete Protista kingdom. They are classified based on their flagellar structures, and they are considered to be the most basal flagellate lineage. Phylogenomic analyses split the members of Excavata into three different and not all closely related groups: Discobids, Metamonads and Malawimonads. Except for Euglenozoa, they are all non-photosynthetic. Characteristics Most excavates are unicellular, heterotrophic flagellates. Only the Euglenozoa are photosynthetic. In some (particularly anaerobic intestinal parasites), the mitochondria have been greatly ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eukaryota
Eukaryotes () are organisms whose Cell (biology), cells have a cell nucleus, nucleus. All animals, plants, fungi, and many unicellular organisms, are Eukaryotes. They belong to the group of organisms Eukaryota or Eukarya, which is one of the Three-domain system, three domains of life. Bacteria and Archaea (both prokaryotes) make up the other two domains. The eukaryotes are usually now regarded as having emerged in the Archaea or as a sister of the Asgard (archaea), Asgard archaea. This implies that there are only Two-domain system, two domains of life, Bacteria and Archaea, with eukaryotes incorporated among archaea. Eukaryotes represent a small minority of the number of organisms, but, due to their generally much larger size, their collective global biomass (ecology), biomass is estimated to be about equal to that of prokaryotes. Eukaryotes emerged approximately 2.3–1.8 billion years ago, during the Proterozoic eon, likely as Flagellated cell, flagellated phagotrophs. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
