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Arcella Sp
''Arcella'' is a genus of testate amoebae in the order Arcellinida, usually found in freshwaters and mosses, and rarely in soils. A key characteristic of ''Arcella'' is the circular test with a hole on its center from where finger-like pseudopods emerge. It is one of the largest testacean genera. Anatomy An ''Arcella'' is typically enclosed in a chitinous, umbrella-shaped test (or shell) that has a single central aperture through which the pseudopods – which are used for locomotion – extend out. In some species the aperture is surrounded by a ring of pores. The test is composed of organic material with a diameter of up to 300 µm and is transparent or light-yellow-colored in young ''Arcella'', but browns while aging due to the progressive deposition of iron and manganese compounds.Ralf Meisterfeld and Edward Mitchell (2008)"''Arcella'' Ehrenberg 1832" Contrary to other genera, no gravel chips or other foreign bodies are inserted to strengthen the housing. Different s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eukaryota
Eukaryotes () are organisms whose cells have a 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 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. This implies that there are only 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 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 phagotrophs. Their name comes from the Greek εὖ (''eu'', "well" or "good") and κάρυον (''karyon'', "nut" or "kernel"). E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arcella Megastoma
''Arcella'' is a genus of testate amoebae in the order Arcellinida, usually found in freshwaters and mosses, and rarely in soils. A key characteristic of ''Arcella'' is the circular test with a hole on its center from where finger-like pseudopods emerge. It is one of the largest testacean genera. Anatomy An ''Arcella'' is typically enclosed in a chitinous, umbrella-shaped test (or shell) that has a single central aperture through which the pseudopods – which are used for locomotion – extend out. In some species the aperture is surrounded by a ring of pores. The test is composed of organic material with a diameter of up to 300 µm and is transparent or light-yellow-colored in young ''Arcella'', but browns while aging due to the progressive deposition of iron and manganese compounds.Ralf Meisterfeld and Edward Mitchell (2008)"''Arcella'' Ehrenberg 1832" Contrary to other genera, no gravel chips or other foreign bodies are inserted to strengthen the housing. Different spec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arcella Costata
''Arcella'' is a genus of testate amoebae in the order Arcellinida, usually found in freshwaters and mosses, and rarely in soils. A key characteristic of ''Arcella'' is the circular test with a hole on its center from where finger-like pseudopods emerge. It is one of the largest testacean genera. Anatomy An ''Arcella'' is typically enclosed in a chitinous, umbrella-shaped test (or shell) that has a single central aperture through which the pseudopods – which are used for locomotion – extend out. In some species the aperture is surrounded by a ring of pores. The test is composed of organic material with a diameter of up to 300 µm and is transparent or light-yellow-colored in young ''Arcella'', but browns while aging due to the progressive deposition of iron and manganese compounds.Ralf Meisterfeld and Edward Mitchell (2008)"''Arcella'' Ehrenberg 1832" Contrary to other genera, no gravel chips or other foreign bodies are inserted to strengthen the housing. Different spec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arcella Conica
''Arcella'' is a genus of testate amoebae in the order Arcellinida, usually found in freshwaters and mosses, and rarely in soils. A key characteristic of ''Arcella'' is the circular test with a hole on its center from where finger-like pseudopods emerge. It is one of the largest testacean genera. Anatomy An ''Arcella'' is typically enclosed in a chitinous, umbrella-shaped test (or shell) that has a single central aperture through which the pseudopods – which are used for locomotion – extend out. In some species the aperture is surrounded by a ring of pores. The test is composed of organic material with a diameter of up to 300 µm and is transparent or light-yellow-colored in young ''Arcella'', but browns while aging due to the progressive deposition of iron and manganese compounds.Ralf Meisterfeld and Edward Mitchell (2008)"''Arcella'' Ehrenberg 1832" Contrary to other genera, no gravel chips or other foreign bodies are inserted to strengthen the housing. Different spec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arcella Catinus
''Arcella'' is a genus of testate amoebae in the order Arcellinida, usually found in freshwaters and mosses, and rarely in soils. A key characteristic of ''Arcella'' is the circular test with a hole on its center from where finger-like pseudopods emerge. It is one of the largest testacean genera. Anatomy An ''Arcella'' is typically enclosed in a chitinous, umbrella-shaped test (or shell) that has a single central aperture through which the pseudopods – which are used for locomotion – extend out. In some species the aperture is surrounded by a ring of pores. The test is composed of organic material with a diameter of up to 300 µm and is transparent or light-yellow-colored in young ''Arcella'', but browns while aging due to the progressive deposition of iron and manganese compounds.Ralf Meisterfeld and Edward Mitchell (2008)"''Arcella'' Ehrenberg 1832" Contrary to other genera, no gravel chips or other foreign bodies are inserted to strengthen the housing. Different spec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arcella Brasiliensis
''Arcella'' is a genus of testate amoebae in the order Arcellinida, usually found in freshwaters and mosses, and rarely in soils. A key characteristic of ''Arcella'' is the circular test with a hole on its center from where finger-like pseudopods emerge. It is one of the largest testacean genera. Anatomy An ''Arcella'' is typically enclosed in a chitinous, umbrella-shaped test (or shell) that has a single central aperture through which the pseudopods – which are used for locomotion – extend out. In some species the aperture is surrounded by a ring of pores. The test is composed of organic material with a diameter of up to 300 µm and is transparent or light-yellow-colored in young ''Arcella'', but browns while aging due to the progressive deposition of iron and manganese compounds.Ralf Meisterfeld and Edward Mitchell (2008)"''Arcella'' Ehrenberg 1832" Contrary to other genera, no gravel chips or other foreign bodies are inserted to strengthen the housing. Different spec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arcella Artocrea
''Arcella'' is a genus of testate amoebae in the order Arcellinida, usually found in freshwaters and mosses, and rarely in soils. A key characteristic of ''Arcella'' is the circular test with a hole on its center from where finger-like pseudopods emerge. It is one of the largest testacean genera. Anatomy An ''Arcella'' is typically enclosed in a chitinous, umbrella-shaped test (or shell) that has a single central aperture through which the pseudopods – which are used for locomotion – extend out. In some species the aperture is surrounded by a ring of pores. The test is composed of organic material with a diameter of up to 300 µm and is transparent or light-yellow-colored in young ''Arcella'', but browns while aging due to the progressive deposition of iron and manganese compounds.Ralf Meisterfeld and Edward Mitchell (2008)"''Arcella'' Ehrenberg 1832" Contrary to other genera, no gravel chips or other foreign bodies are inserted to strengthen the housing. Different spec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arcella Arenaria
''Arcella'' is a genus of testate amoebae in the order Arcellinida, usually found in freshwaters and mosses, and rarely in soils. A key characteristic of ''Arcella'' is the circular test with a hole on its center from where finger-like pseudopods emerge. It is one of the largest testacean genera. Anatomy An ''Arcella'' is typically enclosed in a chitinous, umbrella-shaped test (or shell) that has a single central aperture through which the pseudopods – which are used for locomotion – extend out. In some species the aperture is surrounded by a ring of pores. The test is composed of organic material with a diameter of up to 300 µm and is transparent or light-yellow-colored in young ''Arcella'', but browns while aging due to the progressive deposition of iron and manganese compounds.Ralf Meisterfeld and Edward Mitchell (2008)"''Arcella'' Ehrenberg 1832" Contrary to other genera, no gravel chips or other foreign bodies are inserted to strengthen the housing. Different spec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ciliate
The ciliates are a group of alveolates characterized by the presence of hair-like organelles called cilia, which are identical in structure to eukaryotic flagella, but are in general shorter and present in much larger numbers, with a different undulating pattern than flagella. Cilia occur in all members of the group (although the peculiar Suctoria only have them for part of their life cycle) and are variously used in swimming, crawling, attachment, feeding, and sensation. Ciliates are an important group of protists, common almost anywhere there is water—in lakes, ponds, oceans, rivers, and soils. About 4,500 unique free-living species have been described, and the potential number of extant species is estimated at 27,000–40,000. Included in this number are many ectosymbiotic and endosymbiotic species, as well as some obligate and opportunistic parasites. Ciliate species range in size from as little as 10 µm in some colpodeans to as much as 4 mm in length in some ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flagellate
A flagellate is a cell or organism with one or more whip-like appendages called flagella. The word ''flagellate'' also describes a particular construction (or level of organization) characteristic of many prokaryotes and eukaryotes and their means of motion. The term presently does not imply any specific relationship or classification of the organisms that possess flagella. However, the term "flagellate" is included in other terms (such as " dinoflagellate" and " choanoflagellata") which are more formally characterized. Form and behavior Flagella in eukaryotes are supported by microtubules in a characteristic arrangement, with nine fused pairs surrounding two central singlets. These arise from a basal body. In some flagellates, flagella direct food into a cytostome or mouth, where food is ingested. Flagella often support hairs, called mastigonemes, or contain rods. Their ultrastructure plays an important role in classifying eukaryotes. Among protoctists and micros ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Green Algae
The green algae (singular: green alga) are a group consisting of the Prasinodermophyta and its unnamed sister which contains the Chlorophyta and Charophyta/ Streptophyta. The land plants (Embryophytes) have emerged deep in the Charophyte alga as sister of the Zygnematophyceae. Since the realization that the Embryophytes emerged within the green algae, some authors are starting to properly include them. The completed clade that includes both green algae and embryophytes is monophyletic and is referred to as the clade Viridiplantae and as the kingdom Plantae. The green algae include unicellular and colonial flagellates, most with two flagella per cell, as well as various colonial, coccoid and filamentous forms, and macroscopic, multicellular seaweeds. There are about 22,000 species of green algae. Many species live most of their lives as single cells, while other species form coenobia (colonies), long filaments, or highly differentiated macroscopic seaweeds. A few other org ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diatom
A diatom ( Neo-Latin ''diatoma''), "a cutting through, a severance", from el, διάτομος, diátomos, "cut in half, divided equally" from el, διατέμνω, diatémno, "to cut in twain". is any member of a large group comprising several genera of algae, specifically microalgae, found in the oceans, waterways and soils of the world. Living diatoms make up a significant portion of the Earth's biomass: they generate about 20 to 50 percent of the oxygen produced on the planet each year, take in over 6.7 billion metric tons of silicon each year from the waters in which they live, and constitute nearly half of the organic material found in the oceans. The shells of dead diatoms can reach as much as a half-mile (800 m) deep on the ocean floor, and the entire Amazon basin is fertilized annually by 27 million tons of diatom shell dust transported by transatlantic winds from the African Sahara, much of it from the Bodélé Depression, which was once made up of a system of fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
