In taxonomy Alpha taxonomy is the science of finding, describing and categorising organisms, thus leading to the recognition of proposed taxonomic groups, or taxa (singular: taxon), which may then be named, Prasinophytes are a class of the Division Chlorophyta Chlorophyta, a division of green algae, includes about 7000 species of mostly aquatic photosynthetic eukaryotic organisms. Like the land plants , green algae contain chlorophylls a and b, and store food as starch in their plastids. They are related to the Charophyta and Embryophyta (land plants), together making up the Viridiplantae. These are primitive eukaryotic A eukaryote is an organism whose cells contain complex structures enclosed within membranes. Most living organisms, including all animals, plants, fungi, and protists, are eukaryotes. The defining membrane-bound structure that differentiates eukaryotic cells from prokaryotic cells is the nucleus. The presence of a nucleus gives these organisms, marine green algae The green algae are the large group of algae from which the embryophytes (higher plants) emerged. As such, they form a paraphyletic group, although the group including both green algae and embryophytes is monophyletic (and often just known as kingdom Plantae). The green algae include unicellular and colonial flagellates, usually but not always.[2] Its best known genus is Ostreococcus (seen at right), which is considered to be the smallest (ca. 0.95 μm A micrometre or micron is one millionth of a metre, or equivalently one thousandth of a millimetre. It can be written in scientific notation as 1×10−6 m, meaning 1⁄1000000 m) free-living eukaryote A eukaryote is an organism whose cells contain complex structures enclosed within membranes. Most living organisms, including all animals, plants, fungi, and protists, are eukaryotes. The defining membrane-bound structure that differentiates eukaryotic cells from prokaryotic cells is the nucleus. The presence of a nucleus gives these organisms[3] and which has been detected in marine samples around the world. Prasinophytes are thought to have low cellular complexity, that is, they are naked cells that possess single, multiple or no flagellae and contain only a single chloroplast Chloroplasts are organelles found in plant cells and other eukaryotic organisms that conduct photosynthesis. Chloroplasts capture light energy to conserve free energy in the form of ATP and reduce NADP to NADPH through a complex set of processes called photosynthesis and a single mitochondrion In cell biology, a mitochondrion is a membrane-enclosed organelle found in most eukaryotic cells. These organelles range from 0.5–10 micrometers (μm) in diameter. Mitochondria are sometimes described as "cellular power plants" because they generate most of the cell's supply of adenosine triphosphate (ATP), used as a source of chemical. They also have very small genomes for a eukaryote (about 12Mbp).

It has been suggested that a prasinophyte-like flagellate was the ancestor to Chlorophyta Chlorophyta, a division of green algae, includes about 7000 species of mostly aquatic photosynthetic eukaryotic organisms. Like the land plants , green algae contain chlorophylls a and b, and store food as starch in their plastids. They are related to the Charophyta and Embryophyta (land plants), together making up the Viridiplantae and Streptophyta.[4]

Contents

Ecology

Micromonas pusilla

A study of photosynthetic gene-sequence diversity (rbcL) in the Gulf of Mexico The Gulf of Mexico is the ninth largest body of water in the world. Considered a smaller part of the Atlantic Ocean, it is an ocean basin largely surrounded by the North American continent and the island of Cuba. It is bounded on the northeast, north and northwest by the Gulf Coast of the United States, on the southwest and south by Mexico, and on indicated that Prasinophytes are particularly prevalent at the Subsurface Chlorophyll Maximum (SCM)[5] and several different ecotypes of Ostreococcus have been detected in the environment.[6] These ecotypes are distinguished by their adaptation to light intensities. O. lucimarinus is found in high-light environments and represents surface-isolated strains. RCC141 is considered low-light, because these strains were isolated from the lower euphotic zone. O. tauri was isolated from a coastal lagoon and is considered light-polyvalent. Genetic data indicates that distinct molecular differences exist between the different ecotypes that have been detected.[7]

References

  1. ^ Guiry, M.D. & Guiry, G.M. (2007). "Class: Prasinophyceae taxonomy browser". AlgaeBase version 4.2 World-wide electronic publication, National University of Ireland, Galway. http://www.algaebase.org/browse/taxonomy/?id=4345. Retrieved on 2007-09-23.
  2. ^ Sym SD, Pienaar RN (1993). "The class Prasinophyceae". Prog Phycol Res 9: 281–376.
  3. ^ Courties C, Vaquer A, Troussellier M, Lautier J, Chrétiennot-Dinet MJ, Neveux J, Machado C, Claustre H (1994). "Smallest eukaryotic organism". Nature 370: 255. doi The Digital Object Identifier System is a managed system for persistent identification of content-related entities on digital networks. These entities may be content items (digital files, physical objects, abstract works), or any related entities in a content transaction (e.g. licenses, parties, etc.). "DOI" is sometimes used to mean the:10.1038/370255a0.
  4. ^ Kapraun DF (April 2007). "Nuclear DNA content estimates in green algal lineages: chlorophyta and streptophyta". Ann. Bot. 99 (4): 677–701. doi The Digital Object Identifier System is a managed system for persistent identification of content-related entities on digital networks. These entities may be content items (digital files, physical objects, abstract works), or any related entities in a content transaction (e.g. licenses, parties, etc.). "DOI" is sometimes used to mean the:10.1093/aob/mcl294. PMID 17272304. http://aob.oxfordjournals.org/cgi/pmidlookup?view=long&pmid=17272304.
  5. ^ Wawrik B, Paul JH, Campbell L, Griffin D, Houchin L, Fuentes-Ortega A, Müller-Karger F (2003). "Vertical Structure of the Phytoplankton Community Associated with a Coastal Plume in the Gulf of Mexico". Marine Ecology Progress Series 251: 87–101. doi The Digital Object Identifier System is a managed system for persistent identification of content-related entities on digital networks. These entities may be content items (digital files, physical objects, abstract works), or any related entities in a content transaction (e.g. licenses, parties, etc.). "DOI" is sometimes used to mean the:10.3354/meps251087.
  6. ^ Guillou L, Eikrem W, Chrétiennot-Dinnet MJ, Le Gall F, Massana R, Romari K, Pedros-Alio C, Vaulot D (2004). "Diversity of picoplanktonic Prasinophyceae assessed by direct SSU rDNA sequencing of environmental samples and novel isolates retrieved from oceanic and coastal marine ecosystems". Protist 155: 193–214. doi The Digital Object Identifier System is a managed system for persistent identification of content-related entities on digital networks. These entities may be content items (digital files, physical objects, abstract works), or any related entities in a content transaction (e.g. licenses, parties, etc.). "DOI" is sometimes used to mean the:10.1078/143446104774199592.
  7. ^ Rodríguez F, Derelle E, Guillou L, Le Gall F, Vaulot D, Moreau H (2005). "Ecotype diversity in the marine picoeukaryote Ostreococcus (Chlorophyta, Prasinophyceae)". Environmental Microbiology 7: 853–859. doi The Digital Object Identifier System is a managed system for persistent identification of content-related entities on digital networks. These entities may be content items (digital files, physical objects, abstract works), or any related entities in a content transaction (e.g. licenses, parties, etc.). "DOI" is sometimes used to mean the:10.1111/j.1462-2920.2005.00758.x.

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This Alga Algae are a large and diverse group of simple, typically autotrophic organisms, ranging from unicellular to multicellular forms. The largest and most complex marine forms are called seaweeds. They are photosynthetic, like plants, and "simple" because they lack the many distinct organs found in land plants. For that reason they are-related article is a stub. You can help Wikipedia by expanding it.
Classification of Archaeplastida The Archaeplastida are a major line of eukaryotes, comprising the land plants, green and red algae, and a small group called the glaucophytes. All of these organisms have plastids surrounded by two membranes, suggesting they developed directly from endosymbiotic cyanobacteria. In all other groups, plastids are surrounded by three or four membranes, / Plantae sensu lato Plants are living organisms belonging to the kingdom Plantae. They include familiar organisms such as trees, herbs, bushes, grasses, vines, ferns, mosses, and green algae. About 350,000 species of plants, defined as seed plants, bryophytes, ferns and fern allies, are estimated to exist currently. As of 2004, some 287,655 species had been
Rhodophyta The red algae (or Rhodophyta, pronounced /roʊˈdɒfɨtə, ˌroʊdəˈfaɪtə/, from Greek: ῥόδον = rose + φυτόν (phyton) = plant, thus red plant) are one of the oldest groups of eukaryotic algae, and also one of the largest, with about 5,000–6,000 species of mostly multicellular, marine algae, including many notable seaweeds. Other Rhodophyceae · Bangiophyceae Bangiophyceae was a class of red algae; it has since been merged with the Floridophyceae to form the Rhodophyceae. The Bangiophyceae, as defined traditionally, are paraphyletic.. Their taxonomic identification has been difficult because of a lack of distinct morphological features, and the presumed morphological plasticity of the species · Florideophyceae Florideophyceae was a class of red algae. It is now merged with the Bangiaceae into the Rhodophyceae. They were once thought to be the only algae to bear pit connections, but these have since been found in the filamentous stage of the Bangiacae · Goniotrichales · Stylonematophyceae
Glaucocystophyceae The glaucophytes, also known as glaucocystophytes or glaucocystids, are a small group of freshwater microscopic algae. Together with the red algae and Viridiplantae they form the Archaeplastida. However, the relationships between the red algae, green algae and glaucophytes are unclear, in large part due to limited study of the glaucophytes Glaucocystis · Cyanophora · Gloeochaete
Viridiplantae In some classification systems they have been treated as a kingdom, under various names, e.g. Viridiplantae, Chlorobionta, or simply Plantae/ Plantae sensu stricto
Chlorophyta Chlorophyta, a division of green algae, includes about 7000 species of mostly aquatic photosynthetic eukaryotic organisms. Like the land plants , green algae contain chlorophylls a and b, and store food as starch in their plastids. They are related to the Charophyta and Embryophyta (land plants), together making up the Viridiplantae/GA The green algae are the large group of algae from which the embryophytes (higher plants) emerged. As such, they form a paraphyletic group, although the group including both green algae and embryophytes is monophyletic (and often just known as kingdom Plantae). The green algae include unicellular and colonial flagellates, usually but not always Bryopsidophyceae In taxonomy, the Bryopsidophyceae are a class of green algae, in the division Chlorophyta · Chlorophyceae The Chlorophyceae are one of the classes of green algae, distinguished mainly on the basis of ultrastructural morphology. For example the chlorophycean CW clade, and chlorophycean DO clade, are defined by the arrangement of their flagella. Members of the CW clade have flagella that are displaced in a "clockwise" direction eg · Pedinophyceae In taxonomy, the Pedinomonadaceae are a family of algae. They are small single-celled algae. Each cell has a single flagellum. It has been proposed to be either in the Mamiellales or the Ulvophyceae, but it has not been studied enough to confidently place it · Pleurastrophyceae In taxonomy, the Pleurastrophyceae are a class of green algae, in the division Chlorophyta. It was created by Mattox and Stewart in 1984, containing four genera. More recent classifications tend to split the group. On the one hand, Tetraselmis seems to be a sister to the so-called UTC clade , thus making it part of the (paraphyletic) · Prasinophyceae · Trebouxiophyceae In taxonomy, the Trebouxiophyceae are a class of green algae, in the division Chlorophyta · Ulvophyceae The Ulvophyceae or Ulvophytes are class of green algae, distinguished mainly on the basis of ultrastructural morphology. The sea lettuce, Ulva, belongs here. Other well-known members include Ulothrix and Acetabularia. The Ulvophytes are diverse in their morphology and their habitat. Most are seaweeds such as those listed above. Others, such as
Streptophyta Streptophytina is formally a subdivision or subphylum which contains two classes: Charophyceae, containing the Charales order (Charophytes sensu stricto); and Embryophyceae, which contains the embryophytes (land plants, bryophytes, and vascular plants)
Charophyta The Charophyta are a division of green algae, including the closest relatives of the embryophyte plants. In some groups, such as conjugating green algae, flagellate cells do not occur. The latter group does engage in sexual reproduction, and motility does not involve flagella, since they are totally lacking. Flagellate cells in the form of sperm/GA The green algae are the large group of algae from which the embryophytes (higher plants) emerged. As such, they form a paraphyletic group, although the group including both green algae and embryophytes is monophyletic (and often just known as kingdom Plantae). The green algae include unicellular and colonial flagellates, usually but not always
Charophyceae Charophyceae is a taxon of green algae whose exact rank is the matter of some current debate. Some botanists recommend expanding the existing plant kingdom to include charophyceans and chlorophytes while others consider Charophyceae to be a class within either the divisions Chlorophyta, Streptophytina, or Streptophyta. Other systematists classify Charales Charales is an order of pondweeds, freshwater algae in the division Charophyta. They are green plants believed to be the closest relatives of the green land plants. Linnaeus established the genus in 1753
Coleochaetophyceae The Coleochaetales are a family of parenchymous charophyte algae. They questionably include the fossil genus Parka Coleochaetales The Coleochaetales are a family of parenchymous charophyte algae. They questionably include the fossil genus Parka
Zygnematophyceae Zygnematophyceae is an order of green algae. It contains two orders: Zygnematales and Desmidiales Desmidiales Desmids are an order of green algae, comprising around 40 genera and 5,000 to 6,000 species, found mostly but not exclusively in fresh water. Most are unicellular, and are divided into two compartments separated by a narrow bridge or isthmus. Desmids assume a variety of highly symmetrical and generally attractive shapes, which provide the basis · Zygnematales The Zygnematales (Greek: ζυγός + νήμα (nēma) (nom.), νήματος (nēmatos) (gen.)), also called the Conjugales, are an order of green algae, comprising several thousand different species in genera such as the well-known Zygnema and Spirogyra. All the members of this group develop into unbranched filaments, one cell thick, which grow
Embryophyta The embryophytes are the most familiar group of plants. They include trees, flowers, ferns, mosses, and various other green land plants. All are complex multicellular eukaryotes with specialized reproductive organs. With very few exceptions, embryophytes obtain their energy through photosynthesis ; and they synthesize their food from carbon/ Plantae sensu strictissimo
Bryophytes Bryophytes are all embryophytes that are non-vascular: they have tissues and enclosed reproductive systems, but they lack vascular tissue that circulates liquids. They neither have flowers nor produce seeds, reproducing via spores. The term bryophyte comes from Greek βρύον - bryon, "tree-moss, oyster-green" + φυτόν - fyton & (non-vascular Non-vascular plants is a general term for those plants without a vascular system . Although non-vascular plants lack these particular tissues, a number of non-vascular plants possess tissues specialized for internal transport of water) Marchantiophyta The Marchantiophyta [mɑːˌkæntiˈɑːfɪtə] (help·info) are a division of bryophyte plants commonly referred to as hepatics or liverworts. Like other bryophytes, they have a gametophyte-dominant life cycle, in which cells of the plant carry only a single set of genetic information · Anthocerotophyta Hornworts are a group of bryophytes, or non-vascular plants, comprising the division Anthocerotophyta. The common name refers to the elongated horn-like structure, which is the sporophyte. The flattened, green plant body of a hornwort is the gametophyte plant · Bryophyta "Moss" Mosses are small, soft plants that are typically 1–10 cm tall, though some species are much larger. They commonly grow close together in clumps or mats in damp or shady locations. They do not have flowers or seeds, and their simple leaves cover the thin wiry stems. At certain times mosses produce spore capsules which may appear as beak-like · Horneophytopsida Horneophytopsida is a class of early vascular plants including the genera Caia, Tortilicaulis, and Horneophyton. Although formerly classified among the Rhyniophyta, the group is distinctive for having branched sporangia, and lacking true xylem
Tracheophyta Vascular plants are those plants that have lignified tissues for conducting water, minerals, and photosynthetic products through the plant. Vascular plants include the ferns, clubmosses, flowering plants, conifers and other gymnosperms. Scientific names for the group include Tracheophyta and Tracheobionta, but neither name is very widely used.[
Lycopodiophyta The Division Lycopodiophyta is a tracheophyte subdivision of the Kingdom Plantae. It is the oldest extant (living) vascular plant division at around 420 million years old,[citation needed] and includes some of the most "primitive" extant species. These species reproduce by shedding spores and have macroscopic alternation of generations, Isoetopsida (Isoetales, Selaginellales) · Lycopodiopsida (Lycopodiales)
Euphyllophyta Moniliformopses (Equisetopsida, Filicopsida, Psilotopsida) Spermatophyta: Gymnosperm (Pinophyta, Cycadophyta, Ginkgophyta, Gnetophyta) · Magnoliophyta
see also list of plant orders

Categories: Green algae | Algae taxonomic classes

 

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'Prasinophyceae' Blogs
Plastid ndh genes in plant evolution - SciTopics
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Plastid ndh genes in plant evolution - SciTopics

Bartolome Sabater

2008-05-15 08:10:05

Within green algae, the Chlorophyta: Chlorophyceae, Trebouxioficea and Ulvophyceae also lack ndh genes, but . Prasinophyceae.​ contain ndh genes in their plastid DNA. Similarly to higher plants, all other Chlorophyta (Charophyceae) (many . ...

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