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Anisonemidae
Anisonemidae is a small family of euglenid algae, with two accepted genera. It is the only family in the order Anisonemida. Description The family consists of single-celled organisms with a larger posterior flagellum by means of which they are able to glide. They are phagotrophic, meaning that they feed by engulfing particles of food, and are non-photosynthetic. Taxonomy The family was established by William Saville-Kent in a work published in 1880–1881. Saville-Kent used a much wider circumscription than more recent sources. Historically, phagotrophic euglenids have been treated as animals, and named under the International Code of Zoological Nomenclature, hence the family name ending "-idae". Genera , two genera are accepted: *''Anisonema'' Dujardin, 1841 *'' Dinema'' Perty, 1852 (syn. ''Dinematomonas'' P.C.Silva, 1960) A third genus, ''Heteronema'' Dujardin, 1841, is listed by some sources. The status of the genus is unclear; it appears to be polyphyletic, with some specie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Euglenozoa
Euglenozoa are a large group of flagellate Discoba. They include a variety of common free-living species, as well as a few important parasites, some of which infect humans. Euglenozoa are represented by four major groups, ''i.e.,'' Kinetoplastea, Diplonemea, Euglenida, and Symbiontida. Euglenozoa are unicellular, mostly around in size, although some euglenids get up to long. Structure Most euglenozoa have two flagella, which are inserted parallel to one another in an apical or subapical pocket. In some these are associated with a cytostome or mouth, used to ingest bacteria or other small organisms. This is supported by one of three sets of microtubules that arise from the flagellar bases; the other two support the dorsal and ventral surfaces of the cell. Some other euglenozoa feed through absorption, and many euglenids possess chloroplasts, the only eukaryotes outside Diaphoretickes to do so without performing kleptoplasty, and so obtain energy through photosynthesis. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dinema (alga)
''Dinema'', synonym ''Dinematomonas'', is a genus of flagellated algae in the phylum Euglenozoa. Description Like other members of the family Anisonemidae, ''Dinema'' consists of single-celled organisms with a larger posterior flagellum by means of which they are able to glide. They are phagotrophic, meaning that they feed by engulfing particles of food, and are non-photosynthetic. Taxonomy The algal genus ''Dinema'' was established by Perty in 1852. It is an illegitimate name under the International Code of Nomenclature for algae, fungi, and plants. The genus name was first published in 1826 for a genus of orchids. In spite of this, it was accepted by AlgaeBase . Other sources use the genus name ''Dinematomonas'' P.C.Silva. ''Dinema'' is an acceptable name under the International Code of Zoological Nomenclature. ''Dinema'' is probably paraphyletic with respect to ''Anisonema''. Species , AlgaeBase AlgaeBase is a global species database of information on all groups of alga ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Euglenales
Euglenales (also known as Euglenida) is an order of flagellates in the phylum Euglenozoa. The family includes the most well-known euglenoid genus, '' Euglena'', as well as other common genera like '' Phacus'' and '' Lepocinclis''. Nomenclature The order Euglenales is also known by the name Euglenida. The origin of this dual naming system is because of the history of protists. Euglenids have been treated as both algae and protozoans, which are governed by separate nomenclature codes. If classified as an alga, it would fall under the International Code of Botanical Nomenclature (ICBN) and its correct name would be Euglenales; if classified as a protozoan, it would fall under the International Code of Zoological Nomenclature (ICZN) and would be called Euglenida. Euglenids such as these are considered to be ambiregnal protists due to their parallel naming systems. Description Euglenales consists mostly of freshwater organisms, in contrast to its sister Eutreptiales which is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Algae
Algae ( , ; : alga ) is an informal term for any organisms of a large and diverse group of photosynthesis, photosynthetic organisms that are not plants, and includes species from multiple distinct clades. Such organisms range from unicellular microalgae, such as cyanobacteria, ''Chlorella'', and diatoms, to multicellular macroalgae such as kelp or brown algae which may grow up to in length. Most algae are aquatic organisms and lack many of the distinct cell and tissue types, such as stomata, xylem, and phloem that are found in embryophyte, land plants. The largest and most complex marine algae are called seaweeds. In contrast, the most complex freshwater forms are the Charophyta, a Division (taxonomy), division of green algae which includes, for example, ''Spirogyra'' and stoneworts. Algae that are carried passively by water are plankton, specifically phytoplankton. Algae constitute a Polyphyly, polyphyletic group because they do not include a common ancestor, and although Eu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flagellum
A flagellum (; : flagella) (Latin for 'whip' or 'scourge') is a hair-like appendage that protrudes from certain plant and animal sperm cells, from fungal spores ( zoospores), and from a wide range of microorganisms to provide motility. Many protists with flagella are known as flagellates. A microorganism may have from one to many flagella. A gram-negative bacterium '' Helicobacter pylori'', for example, uses its flagella to propel itself through the stomach to reach the mucous lining where it may colonise the epithelium and potentially cause gastritis, and ulcers – a risk factor for stomach cancer. In some swarming 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phagocytosis
Phagocytosis () is the process by which a cell (biology), cell uses its plasma membrane to engulf a large particle (≥ 0.5 μm), giving rise to an internal compartment called the phagosome. It is one type of endocytosis. A cell that performs phagocytosis is called a phagocyte. In a Multicellular organism, multicellular organism's immune system, phagocytosis is a major mechanism used to remove pathogens and cell debris. The ingested material is then digested in the phagosome. Bacteria, dead tissue cells, and small mineral particles are all examples of objects that may be phagocytized. Some protozoa use phagocytosis as means to obtain nutrients. The two main cells that do this are the Macrophages and the Neutrophils of the immune system. Where phagocytosis is used as a means of feeding and provides the organism part or all of its nourishment, it is called phagotrophy and is distinguished from osmotrophy, which is nutrition taking place by absorption. History The history of phag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photosynthesis
Photosynthesis ( ) is a system of biological processes by which photosynthetic organisms, such as most plants, algae, and cyanobacteria, convert light energy, typically from sunlight, into the chemical energy necessary to fuel their metabolism. ''Photosynthesis'' usually refers to oxygenic photosynthesis, a process that produces oxygen. Photosynthetic organisms store the chemical energy so produced within intracellular organic compounds (compounds containing carbon) like sugars, glycogen, cellulose and starches. To use this stored chemical energy, an organism's cells metabolize the organic compounds through cellular respiration. Photosynthesis plays a critical role in producing and maintaining the oxygen content of the Earth's atmosphere, and it supplies most of the biological energy necessary for complex life on Earth. Some bacteria also perform anoxygenic photosynthesis, which uses bacteriochlorophyll to split hydrogen sulfide as a reductant instead of water, p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
William Saville-Kent
William Saville-Kent (10 July 1845 – 11 October 1908) was an English marine biologist, naturalist, Commissioner and Inspector of Tasmanian Fisheries and author. He is perhaps best-known for his work in the development of the artificial pearl industry. Early life Born in the town of Sidmouth in Devon, South West England on 10 July 1845, William Saville-Kent was the son of Samuel Saville Kent (7 July 1800 – 5 February 1872) and Mary Ann Windus (b. 1808 – May 1852), who was Samuel's first wife. William was the youngest of ten children from his father's first marriage. Samuel was employed as a "Factory Commissioner" for the Home Office, and inspected factories to ensure that they were properly implementing the worker safety measures regulated in the Factory Acts of 1833. As the acts sought to alleviate the harm done to children that were caused by unregulated working conditions in the factories, Samuel's “duties required him to inspect factories that employed women and ch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Circumscription (taxonomy)
In biological taxonomy, circumscription is the content of a taxon, that is, the delimitation of which subordinate taxa are parts of that taxon. For example, if we determine that species X, Y, and Z belong in genus A, and species T, U, V, and W belong in genus B, those are our circumscriptions of those two genera. Another systematist might determine that T, U, V, W, X, Y, and Z all belong in genus A. Agreement on circumscriptions is not governed by the Codes of Zoological or Botanical Nomenclature, and must be reached by scientific consensus. A goal of biological taxonomy is to achieve a stable circumscription for every taxon. This goal conflicts, at times, with the goal of achieving a natural classification that reflects the evolutionary history of divergence of groups of organisms. Balancing these two goals is a work in progress, and the circumscriptions of many taxa that had been regarded as stable for decades are in upheaval in the light of rapid developments in molecu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Code Of Zoological Nomenclature
The International Code of Zoological Nomenclature (ICZN) is a widely accepted Convention (norm), convention in zoology that rules the formal scientific name, scientific naming of organisms treated as animals. It is also informally known as the ICZN Code, for its formal author, the International Commission on Zoological Nomenclature (which shares the acronym "ICZN"). The rules principally regulate: * How names are correctly established in the frame of Binomial nomenclature, binominal nomenclature * How to determine whether a given name is Available name, available * Which available name must be used in case of name conflicts (Valid name (zoology), valid name) * How scientific literature must cite names Zoological nomenclature is independent of other systems of nomenclature, for example botanical nomenclature. This implies that animals can have the same generic names as plants (e.g. there is a genus ''Abronia (other), Abronia'' in both animals and plants). The rules and re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anisonema
''Anisonema'' is a genus of colorless flagellates that occur in marine, brackish, and freshwater habitats. The cell is typically ovoid, somewhat flattened, and rigid. The name ''Anisonema'' derives from Greek for "unequal thread", in reference to the two flagella A flagellum (; : flagella) (Latin for 'whip' or 'scourge') is a hair-like appendage that protrudes from certain plant and animal sperm cells, from fungal spores ( zoospores), and from a wide range of microorganisms to provide motility. Many pr ... that are of unequal lengths. The shorter flagellum extends forwards and propels movement with a sweeping motion, while the longer flagellum, up to three times the length of the cell, trails behind, with jerking contractions. The genus was first named by French biologist Félix Dujardin his 1841 ''Histoire naturelle des zoophytes. Infusoires, comprenant la physiologie et la classification de ces animaux, et la manière de les étudier à l'aide du microscope''. , there a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heteronema
''Heteronema'' is a genus of phagotrophic, flagellated euglenoids that are most widely distributed in fresh water environments.Guiry, M. D.; Guiry, G. M. (2012). “Heteronema Dujardin, 1841”. Retrieved February 14, 2019, fro/ref> This genus consists of two very distinguishable morphogroups that are phylogenetically closely related.Lax, G.; Simpson, A. G. (2013). “Combining Molecular Data with Classical Morphology for Uncultured Phagotrophic Euglenids (Excavata): A Single-Cell Approach". Journal of Eukaryotic Microbiology. 6: 615-625doi: 10.1111/jeu.12068/ref>Lee, Won J. (2011). “Free-living benthic heterotrophic euglenids from Botany Bay, Australia”. Marine Biology Research. 8 (1): 3-27doi: 10.1080/17451000.2011.596545/ref> These morphogroups are deciphered based on shape, locomotion, and other ultrastructural traits. However, this genus does pose taxonomic problems due to the varying historical descriptions of ''Heteronema'' species and their similarity to the genus ''Pe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
