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Cryptophyceae
The cryptophyceae are a class of algae, most of which have plastids. About 220 species are known, and they are common in freshwater, and also occur in marine and brackish habitats. Each cell is around 10–50 μm in size and flattened in shape, with an anterior groove or pocket. At the edge of the pocket there are typically two slightly unequal flagella. Some exhibit mixotrophy. Characteristics Cryptophytes are distinguished by the presence of characteristic extrusomes called ejectosomes or ejectisomes, which consist of two connected spiral ribbons held under tension. If the cells are irritated either by mechanical, chemical or light stress, they discharge, propelling the cell in a zig-zag course away from the disturbance. Large ejectosomes, visible under the light microscope, are associated with the pocket; smaller ones occur underneath the periplast, the cryptophyte-specific cell surrounding. Except for ''Chilomonas'', which has leucoplasts, cryptophytes have one or two ch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cryptophyta Cell Scheme
The cryptophyceae are a class of algae, most of which have plastids. About 220 species are known, and they are common in freshwater, and also occur in marine and brackish habitats. Each cell is around 10–50 μm in size and flattened in shape, with an anterior groove or pocket. At the edge of the pocket there are typically two slightly unequal flagella. Some exhibit mixotrophy. Characteristics Cryptophytes are distinguished by the presence of characteristic extrusomes called ejectosomes or ejectisomes, which consist of two connected spiral ribbons held under tension. If the cells are irritated either by mechanical, chemical or light stress, they discharge, propelling the cell in a zig-zag course away from the disturbance. Large ejectosomes, visible under the light microscope, are associated with the pocket; smaller ones occur underneath the periplast, the cryptophyte-specific cell surrounding. Except for ''Chilomonas'', which has leucoplasts, cryptophytes have one or two ch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cryptomonas
''Cryptomonas'' is the name-giving genus of the Cryptomonads established by German biologist Christian Gottfried Ehrenberg in 1831. The algae are common in freshwater habitats and brackish water worldwide and often form blooms in greater depths of lakes. The cells are usually brownish or greenish in color and are characteristic of having a slit-like furrow at the anterior. They are not known to produce any toxins. They are used to feed small zooplankton, which is the food source for small fish in fish farms. Many species of ''Cryptomonas'' can only be identified by DNA sequencing. ''Cryptomonas'' can be found in several marine ecosystems in Australia and South Korea. Etymology ''Cryptomonas'' has the meaning of hidden small flagellates from “crypto” and “monas”. Genome Structure Species within ''Cryptomonas'' contain four genomes: the nuclear, the nucleomorph, the plastid, and mitochondrial genomes. The plastid genome contains 118 kilobase pairs and is a result of o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cryptomonada
Cryptomonada is a proposed super-class of Cryptists linking Cryptophyceae and Goniomonadea, which was first proposed by Cavalier-Smith in 2004. He made this proposal based on three shared morphological characteristics: Presence of a periplast, ejectisomes with secondary scroll, and mitochondrial cristae A crista (; plural cristae) is a fold in the inner membrane of a mitochondrion. The name is from the Latin for ''crest'' or ''plume'', and it gives the inner membrane its characteristic wrinkled shape, providing a large amount of surface area fo ... with flat tubules. Genetic studies as early as 1994 also supported the hypothesis that ''Goniomonas'' was sister to Cryptophyceae. A study in 2018 found strong evidence that the common ancestor of ''Cryptomonada'' was an autotrophic protist. References {{Taxonbar, from=Q65088966 Cryptista ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetragonidiales
Tetragonidiaceae is a family of cryptomonads The cryptomonads (or cryptophytes) are a group of algae, most of which have plastids. They are common in freshwater, and also occur in marine and brackish habitats. Each cell is around 10–50 μm in size and flattened in shape, with an anterio ... which includes two genera. Members of Tetragonidiaceae are distinguished from other cryptomonads by reproduction occurring in a non-motile vegetative phase, as well as the formation of multicellular filaments unlike any other cryptomonad family. References {{Taxonbar, from=Q22915184 Cryptomonads ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cryptista
Cryptista is a clade of algae-like eukaryotes. It is most likely related to Archaeplastida which includes plants and many algae, within the larger group Diaphoretickes. Although it has sometimes placed along with Haptista in the group Hacrobia, within the kingdom Chromista, most recent studies have found that Hacrobia is not a clade. For example, in 2016, a broad phylogenomic study found that cryptists fall within the group Archaeplastida, while haptophytes are closely related to the SAR supergroup. Taxonomy Based on studies done by Cavalier-Smith, Chao & Lewis 2015 *''Corbihelia'' ** Phylum Microheliellida Tedersoo 2017 [Endohelia Cavalier-Smith 2015] *** Class Endohelea Cavalier-Smith 2012 * Clade Cryptista s.s. ** Phylum Palpitophyta Tedersoo 2017 *** Class Palpitea Cavalier-Smith 2012 ** Clade Rollomonadia Cavalier-Smith 2013 stat. nov. *** Phylum Kathablepharidophyta Okamoto & Inouye 2005 [Leucocrypta Cavalier-Smith 2015] **** Class Leucocryptea Cavalier-Smith 2004 [Kathab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chilomonas
''Chilomonas'' is a genus of cryptophytes, including the species ''Chilomonas paramecium''. Chilomonas is a protozoa (heterotroph). Chilomonas is golden brown and has two flagella A flagellum (; ) is a hairlike appendage that protrudes from certain plant and animal sperm cells, and from a wide range of microorganisms to provide motility. Many protists with flagella are termed as flagellates. A microorganism may have f .... References Cryptomonad genera {{Cryptomonad-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mastigonemes
Mastigonemes are lateral "hairs" that attach to protistan flagella. Flimsy hairs attach to the flagella of euglenid flagellates, while stiff hairs occur in stramenopile and cryptophyte protists.Hoek, C. van den, Mann, D. G. and Jahns, H. M. (1995). Algae : An introduction to phycology', Cambridge University Press, UK. Stramenopile hairs are approximately 15 nm in diameter, and usually consist of flexible basal part that inserts into the cell membrane, a tubular shaft that itself terminates in smaller "hairs". They reverse the thrust caused when a flagellum beats. The consequence is that the cell is drawn into the water and particles of food are drawn to the surface of heterotrophic species. Typology of flagella with hairs: *whiplash flagella (= smooth, acronematic flagella): without hairs but may have extensions , e.g., in Opisthokonta *hairy flagella (= tinsel, flimmer, pleuronematic flagella): with hairs (= mastigonemes ''sensu lato''), divided in: **with fine hairs (= ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyrenomonadales
Pyrenomonadales is an order of Cryptophyta The cryptophyceae are a class of algae, most of which have plastids. About 220 species are known, and they are common in freshwater, and also occur in marine and brackish habitats. Each cell is around 10–50 μm in size and flattened in shape .... References Cryptomonads Bikont orders {{Cryptomonad-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cryptomonadales
Cryptomonadales is an Order (biology), order of Cryptomonad, Cryptophyta containing the families Cryptomonadaceae and Hilleaceae. References Cryptomonads Bikont orders {{Cryptomonad-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flagellum
A flagellum (; ) is a hairlike appendage that protrudes from certain plant and animal sperm cells, and from a wide range of microorganisms to provide motility. Many protists with flagella are termed as flagellates. A microorganism may have from one to many flagella. A gram-negative bacterium ''Helicobacter pylori'' for example uses its multiple flagella to propel itself through the mucus lining to reach the stomach epithelium, where it may cause a gastric ulcer to develop. In some bacteria the flagellum can also function as a sensory organelle, being sensitive to wetness outside the cell. Across the three domains of Bacteria, Archaea, and Eukaryota the flagellum has a different structure, protein composition, and mechanism of propulsion but shares the same function of providing motility. The Latin word means " whip" to describe its lash-like swimming motion. The flagellum in archaea is called the archaellum to note its difference from the bacterial flagellum. Eukaryotic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Incertae Sedis
' () or ''problematica'' is a term used for a taxonomic group where its broader relationships are unknown or undefined. Alternatively, such groups are frequently referred to as "enigmatic taxa". In the system of open nomenclature, uncertainty at specific taxonomic levels is indicated by ' (of uncertain family), ' (of uncertain suborder), ' (of uncertain order) and similar terms. Examples *The fossil plant '' Paradinandra suecica'' could not be assigned to any family, but was placed ''incertae sedis'' within the order Ericales when described in 2001. * The fossil ''Gluteus minimus'', described in 1975, could not be assigned to any known animal phylum. The genus is therefore ''incertae sedis'' within the kingdom Animalia. * While it was unclear to which order the New World vultures (family Cathartidae) should be assigned, they were placed in Aves ''incertae sedis''. It was later agreed to place them in a separate order, Cathartiformes. * Bocage's longbill, ''Motacilla bocagii' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Red Alga
Red algae, or Rhodophyta (, ; ), are one of the oldest groups of eukaryotic algae. The Rhodophyta also comprises one of the largest phyla of algae, containing over 7,000 currently recognized species with taxonomic revisions ongoing. The majority of species (6,793) are found in the Florideophyceae (Class (biology), class), and mostly consist of multicellular, ocean, marine algae, including many notable seaweed, seaweeds. Red algae are abundant in marine habitats but relatively rare in freshwaters. Approximately 5% of red algae species occur in freshwater environments, with greater concentrations found in warmer areas. Except for two coastal cave dwelling species in the asexual class Cyanidiophyceae, there are no terrestrial species, which may be due to an evolutionary bottleneck in which the last common ancestor lost about 25% of its core genes and much of its evolutionary plasticity. The red algae form a distinct group characterized by having eukaryotic cells without flagella and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
