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Sphaeropleales Genera
Sphaeropleales is an order of green algae that used to be called Chlorococcales. The order includes some of the most common freshwater planktonic algae such as ''Scenedesmus'' and ''Pediastrum''. The Spaeropleales includes vegetatively non-motile unicellular or colonial taxa that have biflagellate zoospores with flagella that are directly opposed in direction (the DO arrangement): '' Sphaeroplea'', '' Atractomorpha'', '' Neochloris'', ''Hydrodictyon'', and ''Pediastrum''. All of these taxa have basal body core connections. With an increase in the number of taxa for which sequence data are available, there is evidence of an expanded DO clade that includes additional zoosporic ('' Bracteacoccus'', '' Schroederia'') and some strictly autosporic genera such as ''Ankistrodesmus'', ''Scenedesmus ''Scenedesmus'' is a genus of green algae, in the class Chlorophyceae. They are colonial and non-motile. Taxonomy Currently, there are 74 taxonomically accepted species of ''Scenedesmus' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pediastrum Duplex
''Pediastrum duplex'' is a species of fresh water green algae in the genus ''Pediastrum ''Pediastrum'' is a genus of green algae, in the family Hydrodictyaceae. It is a photoautotrophic, nonmotile coenobial (fixed number of cells) green algae that inhabits freshwater environments. Morphology ''Pediastrum'' is a genus usually lo ...''. They form nonmotile coenobia (colonies) with a fixed number of cells. These coenobia are flat and have a circular shape. The cell bodies are polygonal, are granulated and have horn-like projections. They reproduce these autocolonies asexually. The colonies usually contain 8 to 32 cells, with examples of 4, 64 or 128 occurring rarely. Infraspecies ''Pediastrum duplex brachylobum'' ''Pediastrum duplex clathratum'' ''Pediastrum duplex cohaerens'' ''Pediastrum duplex duplex'' ''Pediastrum duplex'' f. ''denticulatum'' Isabella & R.J. Patel ''Pediastrum duplex gracillimum'' ''Pediastrum duplex regulosum'' ''Pediastrum duplex reticulatum'' ''Pe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zoospore
A zoospore is a motile asexual spore that uses a flagellum for locomotion. Also called a swarm spore, these spores are created by some protists, bacteria, and fungi to propagate themselves. Diversity Flagella types Zoospores may possess one or more distinct types of flagella - tinsel or "decorated", and whiplash, in various combinations. *Tinsellated (straminipilous) flagella have lateral filaments known as mastigonemes perpendicular to their main axis, which allow for more surface area, and disturbance of the medium, giving them the property of a rudder, that is, used for steering. *Whiplash flagella are straight, to power the zoospore through its medium. Also, the "default" zoospore only has the propelling, whiplash flagella. Both tinsel and whiplash flagella beat in a sinusoidal wave pattern, but when both are present, the tinsel beats in the opposite direction of the whiplash, to give two axes of control of motility. Morphological types In eukaryotes, the four main types ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unicellular
A unicellular organism, also known as a single-celled organism, is an organism that consists of a single cell, unlike a multicellular organism that consists of multiple cells. Organisms fall into two general categories: prokaryotic organisms and eukaryotic organisms. All prokaryotes are unicellular and are classified into bacteria and archaea. Many eukaryotes are multicellular, but some are unicellular such as protozoa, unicellular algae, and unicellular fungi. Unicellular organisms are thought to be the oldest form of life, with early protocells possibly emerging 3.8–4.0 billion years ago. Although some prokaryotes live in colonies, they are not specialised cells with differing functions. These organisms live together, and each cell must carry out all life processes to survive. In contrast, even the simplest multicellular organisms have cells that depend on each other to survive. Most multicellular organisms have a unicellular life-cycle stage. Gametes, for example, are r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pediastrum
''Pediastrum'' is a genus of green algae, in the family Hydrodictyaceae. It is a photoautotrophic, nonmotile coenobial (fixed number of cells) green algae that inhabits freshwater environments. Morphology ''Pediastrum'' is a genus usually look like a green star in the pond or lake. They are coenobial green algae composed of 22 to 27 cells, which are orderly arranged in a circular, flat disk. The diameter of a single coenobium can range from 20 to 80 μm, so they belong to the group of microalgae. Cells in ''Pediastrum'' can be divided into interior cells and peripheral cells by position in the coenobium or their shapes. Some of the species have intracellular cell spaces between interior cells, while some would closely aggregate together. The peripheral cells surround outside the interior cells, and they usually possess bristles, V-liked cutting edges, or wavy projections. Phylogeny The genus of ''Pediastrum'' belongs to the Hydrodictyaceae family, along with '' Psuedopediast ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scenedesmus
''Scenedesmus'' is a genus of green algae, in the class Chlorophyceae. They are colonial and non-motile. Taxonomy Currently, there are 74 taxonomically accepted species of ''Scenedesmus''. Additionally, several subgenera have been identified, but vary according to the source. Hegewald denotes ''Acutodesmus'', '' Desmodesmus'', and ''Scenedesmus'' as the three major categories. ''Acutodesmus'' is characterized as having acute cell poles, while ''Desmodesmus'' and ''Scenedesmus'' have obtuse/truncated cell poles (differentiated by the presence or absence of spines respectively). Fossil records date ''Scenedesmus'' from 70 to 100 million years ago with ''Desmodesmus'' suspected to be the youngest of these three groups. Basic biology ''Scenedesmus'' is one of the most common freshwater algae genera; however, the extremely diverse morphologies found within species make identification difficult.Lürling, Miquel. The Smell of Water: Grazer-Induced Colony Formation in Scenedesmus. Thes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plankton
Plankton are the diverse collection of organisms found in Hydrosphere, water (or atmosphere, air) that are unable to propel themselves against a Ocean current, current (or wind). The individual organisms constituting plankton are called plankters. In the ocean, they provide a crucial source of food to many small and large aquatic organisms, such as bivalves, fish and whales. Marine plankton include bacteria, archaea, algae, protozoa and drifting or floating animals that inhabit the saltwater of oceans and the brackish waters of estuaries. Freshwater plankton are similar to marine plankton, but are found in the freshwaters of lakes and rivers. Plankton are usually thought of as inhabiting water, but there are also airborne versions, the aeroplankton, that live part of their lives drifting in the atmosphere. These include plant spores, pollen and wind-scattered seeds, as well as microorganisms swept into the air from terrestrial dust storms and oceanic plankton swept into the air ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chlorococcales
Chlorococcales is a formerly recognized Order (biology), order of green algae in the Class (biology), class Chlorophyceae. , the type family Chlorococcaceae was placed in the order Chlamydomonadales. Conventionally, many groups of coccoid green algae were lumped in the order Chlorococcales sensu lato by Komárek & Fott (1983), based on Pascher's (1918) idea of establishing orders according to life forms. However, coccoid green algae are currently placed in several orders of Chlorophyceae, Trebouxiophyceae, Ulvophyceae (e.g., ''Chlorocystis'') and Prasinophyceae within the division Chlorophyta, or in the division Charophyta (e.g., Chlorokybales, Desmidiales). Families According to Komárek & Fott (1983): * Chlorococcaceae (Chlorococcoideae, Spongiococcoideae) * Palmellaceae (Hormotiloideae, Palmelloideae, Neochloridoideae, Chlorosarcinoideae) * Chlorochytriaceae * Dicranochaetaceae * Characiaceae (Fernandinelloideae, Characioideae, Schroederioideae) * Treubariaceae * Golenki ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Green Alga
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 organ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Order (biology)
Order ( la, wikt:ordo#Latin, ordo) is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between Family_(biology), family and Class_(biology), class. In biological classification, the order is a taxonomic rank used in the classification of organisms and recognized by the nomenclature codes. An immediately higher rank, superorder, is sometimes added directly above order, with suborder directly beneath order. An order can also be defined as a group of related families. What does and does not belong to each order is determined by a taxonomist, as is whether a particular order should be recognized at all. Often there is no exact agreement, with different taxonomists each taking a different position. There are no hard rules that a taxonomist needs to follow in describing or recognizing an order. Some taxa are accepted almost universally, while others are recognized only rarely. The name of an order is usually written with a capital letter. Fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Treubariaceae
Treubariaceae is a family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ... of green algae in the order Sphaeropleales. References External links Chlorophyceae families Sphaeropleales Monogeneric algae families {{Chlorophyceae-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
