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Asterionella
''Asterionella'' is a genus of pennate freshwater diatoms. They are frequently found in star-shaped colonies of individuals. Description ''Asterionella'' average cell size is 60–85 micrometers long and 2–4 micrometers wide. It forms colonies that often consist of eight cells, but can vary up to 20 cells. The cells in the colony are attached by the apex by extracellular matter. By the way the cells are attached to each other, the colonies often look like stars or spiralling chains. Reproduction The silica skeleton of a diatom cell (called the frustule) consists of an epitheca and an hypotheca. The hypotheca is slightly smaller than the epitheca. During asexual reproduction both thecae form the epitheca of the new daughter cell and each daughter produces a new hypotheca. Therefore one daughter cell is always smaller than the original cell. In order to regain their original size, it is usually assumed diatoms have to reproduce sexually, although this has not yet been obs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asterionella Kariana
''Asterionella'' is a genus of pennate freshwater diatoms. They are frequently found in star-shaped colonies of individuals. Description ''Asterionella'' average cell size is 60–85 micrometers long and 2–4 micrometers wide. It forms colonies that often consist of eight cells, but can vary up to 20 cells. The cells in the colony are attached by the apex by extracellular matter. By the way the cells are attached to each other, the colonies often look like stars or spiralling chains. Reproduction The silica skeleton of a diatom cell (called the frustule) consists of an epitheca and an hypotheca. The hypotheca is slightly smaller than the epitheca. During asexual reproduction both thecae form the epitheca of the new daughter cell and each daughter produces a new hypotheca. Therefore one daughter cell is always smaller than the original cell. In order to regain their original size, it is usually assumed diatoms have to reproduce sexually, although this has not yet been obs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asterionella Japonica
''Asterionella'' is a genus of pennate freshwater diatoms. They are frequently found in star-shaped colonies of individuals. Description ''Asterionella'' average cell size is 60–85 micrometers long and 2–4 micrometers wide. It forms colonies that often consist of eight cells, but can vary up to 20 cells. The cells in the colony are attached by the apex by extracellular matter. By the way the cells are attached to each other, the colonies often look like stars or spiralling chains. Reproduction The silica skeleton of a diatom cell (called the frustule) consists of an epitheca and an hypotheca. The hypotheca is slightly smaller than the epitheca. During asexual reproduction both thecae form the epitheca of the new daughter cell and each daughter produces a new hypotheca. Therefore one daughter cell is always smaller than the original cell. In order to regain their original size, it is usually assumed diatoms have to reproduce sexually, although this has not yet been obs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asterionella Glacialis
''Asterionella'' is a genus of pennate freshwater diatoms. They are frequently found in star-shaped colonies of individuals. Description ''Asterionella'' average cell size is 60–85 micrometers long and 2–4 micrometers wide. It forms colonies that often consist of eight cells, but can vary up to 20 cells. The cells in the colony are attached by the apex by extracellular matter. By the way the cells are attached to each other, the colonies often look like stars or spiralling chains. Reproduction The silica skeleton of a diatom cell (called the frustule) consists of an epitheca and an hypotheca. The hypotheca is slightly smaller than the epitheca. During asexual reproduction both thecae form the epitheca of the new daughter cell and each daughter produces a new hypotheca. Therefore one daughter cell is always smaller than the original cell. In order to regain their original size, it is usually assumed diatoms have to reproduce sexually, although this has not yet been obs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asterionella Gracillima
''Asterionella'' is a genus of pennate freshwater diatoms. They are frequently found in star-shaped colonies of individuals. Description ''Asterionella'' average cell size is 60–85 micrometers long and 2–4 micrometers wide. It forms colonies that often consist of eight cells, but can vary up to 20 cells. The cells in the colony are attached by the apex by extracellular matter. By the way the cells are attached to each other, the colonies often look like stars or spiralling chains. Reproduction The silica skeleton of a diatom cell (called the frustule) consists of an epitheca and an hypotheca. The hypotheca is slightly smaller than the epitheca. During asexual reproduction both thecae form the epitheca of the new daughter cell and each daughter produces a new hypotheca. Therefore one daughter cell is always smaller than the original cell. In order to regain their original size, it is usually assumed diatoms have to reproduce sexually, although this has not yet been obs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asterionella Bleakeleyi
''Asterionella'' is a genus of pennate freshwater diatoms. They are frequently found in star-shaped colonies of individuals. Description ''Asterionella'' average cell size is 60–85 micrometers long and 2–4 micrometers wide. It forms colonies that often consist of eight cells, but can vary up to 20 cells. The cells in the colony are attached by the apex by extracellular matter. By the way the cells are attached to each other, the colonies often look like stars or spiralling chains. Reproduction The silica skeleton of a diatom cell (called the frustule) consists of an epitheca and an hypotheca. The hypotheca is slightly smaller than the epitheca. During asexual reproduction both thecae form the epitheca of the new daughter cell and each daughter produces a new hypotheca. Therefore one daughter cell is always smaller than the original cell. In order to regain their original size, it is usually assumed diatoms have to reproduce sexually, although this has not yet been obs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asterionella Ralfsii
''Asterionella'' is a genus of pennate freshwater diatoms. They are frequently found in star-shaped colonies of individuals. Description ''Asterionella'' average cell size is 60–85 micrometers long and 2–4 micrometers wide. It forms colonies that often consist of eight cells, but can vary up to 20 cells. The cells in the colony are attached by the apex by extracellular matter. By the way the cells are attached to each other, the colonies often look like stars or spiralling chains. Reproduction The silica skeleton of a diatom cell (called the frustule) consists of an epitheca and an hypotheca. The hypotheca is slightly smaller than the epitheca. During asexual reproduction both thecae form the epitheca of the new daughter cell and each daughter produces a new hypotheca. Therefore one daughter cell is always smaller than the original cell. In order to regain their original size, it is usually assumed diatoms have to reproduce sexually, although this has not yet been obs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asterionella Formosa
''Asterionella formosa'' is a species of diatom belonging to the family Tabellariaceae. It has cosmopolitan distribution In biogeography, cosmopolitan distribution is the term for the range of a taxon that extends across all or most of the world in appropriate habitats. Such a taxon, usually a species, is said to exhibit cosmopolitanism or cosmopolitism. The ext .... References {{Taxonbar, from=Q49600081 Fragilariophyceae ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fragilariophyceae
Fragilariophyceae is a group of pennate diatom The order Pennales is a traditional subdivision of the heterokont algae known as diatoms. The order is named for the shape of the cell walls (or valves or frustules) of pennate diatoms, which are elongated in valve view. The valves may be lin ...s lacking a raphe. Examples It includes the following genera: Fragilariales *'' Ardissonea'' *'' Asterionella'' *'' Asterionellopsis'' *'' Catacombas'' *'' Diatoma'' *'' Fragilaria'' *'' Fragilariforma'' *'' Grammonema'' *'' Hyalosynedra'' *'' Neofragilaria'' *'' Opephora'' *'' Pseudostaurosira'' *'' Punctastriata'' *'' Staurosira'' *'' Staurosirella'' *'' Synedra'' *'' Synedropsis'' *'' Tabularia'' *'' Ulnaria'' Striatellales *'' Hyalosira'' *'' Striatella'' *'' Toxarium'' Other *'' Climacosphenia'' *'' Cyclophora'' *'' Delphineis'' *'' Protoraphis'' *'' Rhabdonema'' *'' Rhaphoneis'' *'' Tabellaria'' *'' Thalassionema'' References Heterokont classes {{Diatom-stub ... [...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] |
Hypotheca
Hypothec (; german: Hypothek, french: hypothèque, pl, hipoteka, from Lat. ''hypotheca'', from Gk. : hypothēkē), sometimes tacit hypothec, is a term used in civil law systems (e.g. law of entire Continental Europe except Gibraltar) or mixed legal systems (e.g. Scots law, South African law) to refer to a registered non- possessory real security over real estate, but under some jurisdictions it may sometimes also denote security on other collaterals such as securities, intellectual property rights or corporeal movable property, either ships only (ship hypothec) as opposed to other movables covered by a different type of right (pledge) in the legal systems of some countries, or any movables in legal systems of other countries. The common law has two equivalents to the term, namely mortgage and non-possessory lien. Originating in Roman law, a ''hypotheca'' was essentially a non-possessory pledge over a person's entire estate, but during the Renaissance the device was revived by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AlgaeBase
AlgaeBase is a global species database of information on all groups of algae, both marine and freshwater, as well as sea-grass. History AlgaeBase began in March 1996, founded by Michael Guiry. Text was copied from this source, which is available under Attribution 4.0 International (CC BY 4.0)licence. (Sehere. By 2005, the database contained about 65,000 names. In 2013, AlgaeBase and the Flanders Marine Institute (VLIZ) signed an end-user license agreement regarding the Electronic Intellectual Property of AlgaeBase. This allows the World Register of Marine Species (WoRMS) to include taxonomic names of algae in WoRMS, thereby allowing WoRMS, as part of the Aphia database, to make its overview of all described marine species more complete. Synchronisation of the AlgaeBase data with Aphia and WoRMS was undertaken manually until March 2015, but this was very time-consuming, so an online application was developed to semi-automate the synchronisation, launching in 2015 in conju ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chytrid
Chytridiomycota are a division of zoosporic organisms in the kingdom Fungi, informally known as chytrids. The name is derived from the Ancient Greek ('), meaning "little pot", describing the structure containing unreleased zoöspores. Chytrids are one of the early diverging fungal lineages, and their membership in kingdom Fungi is demonstrated with chitin cell walls, a posterior whiplash flagellum, absorptive nutrition, use of glycogen as an energy storage compound, and synthesis of lysine by the -amino adipic acid (AAA) pathway. Chytrids are saprobic, degrading refractory materials such as chitin and keratin, and sometimes act as parasites. There has been a significant increase in the research of chytrids since the discovery of ''Batrachochytrium dendrobatidis'', the causal agent of chytridiomycosis. Classification Species of Chytridiomycota have traditionally been delineated and classified based on development, morphology, substrate, and method of zoöspore discharge. Howev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
