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Pectodictyon Cubicum
''Pectodictyon'' is a genus of green algae in the family Sphaerodictyaceae. It is found free-floating in freshwater habitats as plankton. ''Pectodictyon'' consists of colonies of cells which are tetrahedral or cubic in shape. Each colony has four or eight cells in the corners, covered with mucilage and connected to each other by mucilaginous threads. These colonies may themselves be connected to other colonies to form compound colonies. The cells themselves are spherical or tetrahedral, with parietal chloroplasts with pyrenoids. Asexual reproduction occurs by the formation of autospores, which arrange themselves into the shape of the colony. Sexual reproduction or flagellated life stages have not been observed in this genus. Two species are known: * '' Pectodictyon cubicum'' * ''Pectodictyon pyramidale ''Pectodictyon'' is a genus of green algae in the family Sphaerodictyaceae. It is found free-floating in freshwater habitats as plankton. ''Pectodictyon'' consists of coloni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nomenclature, the genus name forms the first part of the binomial species name for each species within the genus. :E.g. '' Panthera leo'' (lion) and '' Panthera onca'' (jaguar) are two species within the genus ''Panthera''. ''Panthera'' is a genus within the family Felidae. The composition of a genus is determined by taxonomists. The standards for genus classification are not strictly codified, so different authorities often produce different classifications for genera. There are some general practices used, however, including the idea that a newly defined genus should fulfill these three criteria to be descriptively useful: # monophyly – all descendants of an ancestral taxon are grouped together (i.e. phylogenetic analysis should c ... [...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 oth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sphaerodictyaceae
Sphaerodictyaceae is a family of green algae, in the order Chlamydomonadales. The algae are colonial, freshwater phytoplankton Phytoplankton () are the autotrophic (self-feeding) components of the plankton community and a key part of ocean and freshwater ecosystems. The name comes from the Greek words (), meaning 'plant', and (), meaning 'wanderer' or 'drifter'. P .... Cells are spherical, fusiform, or pyramidal, regularly dispersed in a gelatinous matrix with a shape characteristic of the genus. Reproduction occurs by the formation of autospores. References External links AlgaeBaseAlgaTerra databaseIndex Nominum Genericorum Chlorophyceae families Chlamydomonadales Freshwater algae {{Chlorophyceae-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Freshwater Habitat
Freshwater ecosystems are a subset of Earth's aquatic ecosystems. They include lakes, ponds, rivers, streams, springs, bogs, and wetlands. They can be contrasted with marine ecosystems, which have a larger salt content. Freshwater habitats can be classified by different factors, including temperature, light penetration, nutrients, and vegetation. There are three basic types of freshwater ecosystems: Lentic (slow moving water, including pools, ponds, and lakes), lotic (faster moving water, for example streams and rivers) and wetlands (areas where the soil is saturated or inundated for at least part of the time). Freshwater ecosystems contain 41% of the world's known fish species. Freshwater ecosystems have undergone substantial transformations over time, which has impacted various characteristics of the ecosystems. Original attempts to understand and monitor freshwater ecosystems were spurred on by threats to human health (for example cholera outbreaks due to sewage contaminatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plankton
Plankton are the diverse collection of organisms found in water (or air) that are unable to propel themselves against a 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 by sea spray. Though m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mucilage
Mucilage is a thick, gluey substance produced by nearly all plants and some microorganisms. These microorganisms include protists which use it for their locomotion. The direction of their movement is always opposite to that of the secretion of mucilage. It is a polar glycoprotein and an exopolysaccharide. Mucilage in plants plays a role in the storage of water and food, seed germination, and thickening membranes. Cacti (and other succulents) and flax seeds are especially rich sources of mucilage. Occurrence Exopolysaccharides are the most stabilising factor for microaggregates and are widely distributed in soils. Therefore, exopolysaccharide-producing "soil algae" play a vital role in the ecology of the world's soils. The substance covers the outside of, for example, unicellular or filamentous green algae and cyanobacteria. Amongst the green algae especially, the group Volvocales are known to produce exopolysaccharides at a certain point in their life cycle. It occurs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chloroplast
A chloroplast () is a type of membrane-bound organelle known as a plastid that conducts photosynthesis mostly in plant and algal cells. The photosynthetic pigment chlorophyll captures the energy from sunlight, converts it, and stores it in the energy-storage molecules ATP and NADPH while freeing oxygen from water in the cells. The ATP and NADPH is then used to make organic molecules from carbon dioxide in a process known as the Calvin cycle. Chloroplasts carry out a number of other functions, including fatty acid synthesis, amino acid synthesis, and the immune response in plants. The number of chloroplasts per cell varies from one, in unicellular algae, up to 100 in plants like '' Arabidopsis'' and wheat. A chloroplast is characterized by its two membranes and a high concentration of chlorophyll. Other plastid types, such as the leucoplast and the chromoplast, contain little chlorophyll and do not carry out photosynthesis. Chloroplasts are highly dynamic—they ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyrenoid
Pyrenoids are sub-cellular micro-compartments found in chloroplasts of many algae,Giordano, M., Beardall, J., & Raven, J. A. (2005). CO2 concentrating mechanisms in algae: mechanisms, environmental modulation, and evolution. Annu. Rev. Plant Biol., 56, 99-131. and in a single group of land plants, the hornworts.Villarreal, J. C., & Renner, S. S. (2012) Hornwort pyrenoids, carbon-concentrating structures, evolved and were lost at least five times during the last 100 million years. ''Proceedings of the National Academy of Sciences'',109(46), 1873-1887. Pyrenoids are associated with the operation of a carbon-concentrating mechanism (CCM). Their main function is to act as centres of carbon dioxide (CO2) fixation, by generating and maintaining a CO2 rich environment around the photosynthetic enzyme ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO). Pyrenoids therefore seem to have a role analogous to that of carboxysomes in cyanobacteria. Algae are restricted to aqueous ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Autospore
An autospore is a non-motile (non-flagellated) aplanospore that is produced within a parent cell, and has the same shape as the parent cell, before release. Autospores, in addition to zoospore and aplanospore, are one of the three types of spores that algae use to reproduce and spread asexually. Autospores occur in several groups of algae, including Eustigmatophyceae, Dinoflagellates and green algae. For example, the colonial alga '' Dichotomococcus'' produces two autospores per reproducing cell; the autospores escape through a slit in the cell wall A cell wall is a structural layer surrounding some types of cells, just outside the cell membrane. It can be tough, flexible, and sometimes rigid. It provides the cell with both structural support and protection, and also acts as a filtering mech ... and remain attached to the mother cell. Autospore Formation An autospore is defined one of the daughter cells formed by the internal division of a single cell. Autospores are formed a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pectodictyon Cubicum
''Pectodictyon'' is a genus of green algae in the family Sphaerodictyaceae. It is found free-floating in freshwater habitats as plankton. ''Pectodictyon'' consists of colonies of cells which are tetrahedral or cubic in shape. Each colony has four or eight cells in the corners, covered with mucilage and connected to each other by mucilaginous threads. These colonies may themselves be connected to other colonies to form compound colonies. The cells themselves are spherical or tetrahedral, with parietal chloroplasts with pyrenoids. Asexual reproduction occurs by the formation of autospores, which arrange themselves into the shape of the colony. Sexual reproduction or flagellated life stages have not been observed in this genus. Two species are known: * '' Pectodictyon cubicum'' * ''Pectodictyon pyramidale ''Pectodictyon'' is a genus of green algae in the family Sphaerodictyaceae. It is found free-floating in freshwater habitats as plankton. ''Pectodictyon'' consists of coloni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chlamydomonadales Genera
Chlamydomonadales, also known as Volvocales, are an order of flagellated or pseudociliated green algae, specifically of the Chlorophyceae.See the NCBIbr>webpage on Chlamydomonadales Data extracted from the Chlamydomonadales can form planar or spherical colonies. These vary from '' Gonium'' (four to 32 cells) up to '' Volvox'' (500 cells or more). Each cell has two flagella, and is similar in appearance to ''Chlamydomonas'', with the flagella throughout the colony moving in coordination. Both asexual and sexual reproduction occur. In the former, cells divide until they form new colonies, which are then released. In the smaller forms, typically all cells are involved, but larger forms have anterior vegetative and posterior reproductive cells. Sexual reproduction varies from isogamy (both genders produce flagellated gametes of equal size) to oogamy (one gender produces a much larger, nonmotile gamete). The classification of the Chlamydomonadales varies. Very often they are take ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
