NationMaster - Encyclopedia: Brown algae

The Heterokontophyta (Phaeophyta or brown algae, singular: brown alga) is a large group of mostly marine multicellular algae, including many seaweeds of colder Northern Hemisphere waters. They play an important role in marine environments both as food, and for the habitats they can form. For instance Macrocystis, a member of the Laminariales or kelps, may reach 60 m in length, and forms prominent underwater forests. Another example is Sargassum, which creates unique habitats in the tropical waters of the Sargasso Sea. This is one of the few areas where a large biomass of brown algae may be found in tropical waters. Many brown algae such as members of the order Fucales are commonly found along rocky seashores. Some members of the division are used as food for humans. Cropped from PhotoCD image, from Kodak ISO 800 film, taken by k. ... Olympic National Park is located in the U.S. state of Washington, in the far northwestern part of the state known as the Olympic Peninsula. ... Scientific classification or biological classification is a method by which biologists group and categorize species of organisms. ... Kingdoms Eukaryotes are organisms with complex cells, in which the genetic material is organized into membrane-bound nuclei. ... The Chromista are a eukaryotic supergroup, which may be treated as a separate kingdom or included among the Protista. ... Typical classes Colored groups Chrysophyceae (golden algae) Synurophyceae Actinochrysophyceae (axodines) Pelagophyceae Phaeothamniophyceae Bacillariophyceae (diatoms) Bolidophyceae Raphidophyceae Eustigmatophyceae Xanthophyceae (yellow-green algae) Phaeophyceae (brown algae) Colorless groups Oomycetes (water moulds) Hypochytridiomycetes Bicosoecea Labyrinthulomycetes (slime nets) Opalinea Proteromonadea The heterokonts or stramenopiles are a major line of eukaryotes containing about 10,500... Frans Reinhold Kjellman was a professor of botany at the University of Uppsala in Sweden who specialized in marine phycology. ... The worlds oceans as seen from the South Pacific Ocean, before the definition of the Southern Ocean in 2000 For other uses, see Ocean (disambiguation). ... A seaweed (Laurencia) up close: the branches are multicellular and only about 1 mm thick. ... Seaweed-covered rocks in the UK Dead Mans Fingers (Codium fragile) off Massachusetts coast For the band, see; Seaweed (band) For the rock musician, see; Seaweed (musician) Seaweeds are any of a large number of marine benthic algae. ... The Northern Hemisphere is the half of a planets surface (or celestial sphere) that is north of the equator (the word hemisphere literally means half ball). On the Earth, the Northern Hemisphere contains most of the land and about 88-90% of the human population. ... Species Macrocystis pyrifera Macrocystis is a genus of kelp. ... Kelp are large seaweeds, belonging to the brown algae and classified in the order Laminariales. ... Families Alariaceae Chordaceae Laminariaceae Lessoniaceae Phyllariaceae Pseudochordaceae Kelp are large seaweeds (algae), belonging to the brown algae and classified in the order Laminariales. ... The metre, or meter (U.S.), is a measure of length. ... Kelp Forest Kelp forests are a type of marine ecosystem established around colonies of kelp; they contain rich biodiversity. ... Species Sargassum bacciferum, aka. ... An image of the distribution and size of eel larvae shows the approximate location of the Sargasso Sea. ... The tropics are the geographic region of the Earth centered on the equator and limited in latitude by the two tropics: the Tropic of Cancer in the northern hemisphere and the Tropic of Capricorn in the southern hemisphere. ... Genera Ascophyllum Bifurvaria Carpophyllum Coccophora Cystophaera Cystosiera Durvillea Fucus Halidrys Himanthalia Hormosira Pelvetia Pelvetiopsis Phyllospora Sargassum Turbinaria Xaphophora Fucales is an order in the Phylum Phaeophyta or Brown algae. ...

Brown algae belong to a very large group called the hererokonts, a eukaryotic group of organisms distinguished most prominently by having chloroplasts surrounded by four membranes, suggesting an origin from a symbiotic relationship between a basal eukaryote and another eukaryotic organism. Most brown algae contain the pigment fucoxanthin, which is responsible for the distinctive greenish-brown color that gives them their name. Brown algae are unique among heterokonts in developing into multicellular forms with differentiated tissues, but they reproduce by means of flagellate spores, which closely resemble other heterokont cells. Genetic studies show their closest relatives to be the yellow-green algae. Typical classes Colored groups Chrysophyceae (golden algae) Synurophyceae Actinochrysophyceae (axodines) Pelagophyceae Phaeothamniophyceae Bacillariophyceae (diatoms) Bolidophyceae Raphidophyceae Eustigmatophyceae Xanthophyceae (yellow-green algae) Phaeophyceae (brown algae) Colorless groups Oomycetes (water moulds) Hypochytridiomycetes Bicosoecea Labyrinthulomycetes (slime nets) Opalinea Proteromonadea The heterokonts or stramenopiles are a major line of eukaryotes containing about 10,500... Fucoxanthin Fucoxanthin is a carotenoid, with formula C40H60O6. ... Embryonic stem cells differentiate into cells in various body organs. ... Biological tissue is a collection of interconnected cells that perform a similar function within an organism. ... A flagellum (plural, flagella) is a whip-like organelle that many unicellular organisms, and some multicellular ones, use to move about. ... This article is about a biological reproductive structure; for the video game, see Spore (video game). ... Yellow-green algae or xanthophytes are an important group of heterokont algae. ...

Phaeophyta first appear in the fossil record in the Mesozoic, possibly as early as the Jurassic. Their occurrence as fossils is rare due to their generally soft-bodied habit, and scientists continue to debate the identification of some finds. Other algae groups, such as the red algae and green algae have a number of calcareous members, which are more likely to leave evidence in the fossil record than the soft bodies of the brown algae. Miocene fossils of a soft-bodied brown macro algae, Julescrania, have been found well-preserved in Monterey Formation diatomites, but few other certain fossils, particularly of older specimens are known in the fossil record.^[2] Three small ammonite fossils, each approximately 1. ... The Mesozoic Era is one of three geologic eras of the Phanerozoic eon. ... // The image above is believed to be a replaceable fair use image. ... Possible classes Florideophyceae Bangiophyceae Cyanidiophyceae The red algae (Rhodophyta, pronounced /ËˆrÉ™ÊŠdÉ™(ÊŠ)ËŒfÊŒÉªtÉ™/, ancient greek: rhodos phytos = red plant) are a large group of mostly multicellular, marine algae, including many notable seaweeds. ... Divisions Chlorophyta Charophyta The Green algae (singular: Green Alga) are the large group of algae from which the embryophytes (higher plants) emerged. ... Calcareous formed from or containing a high proportion of Calcium carbonate. ... The Miocene epoch is a period of time that extends from about 23 to 5. ... Diatomaceous earth (also known as diatomite, DE or kieselguhr) is a naturally occurring, light-colored, solid material that is easily crumbled into a fine dust. ...

Taxonomy

This is a list of the orders in the class Phaeophyceae:^[3] Scientific classification or biological classification refers to how biologists group and categorize extinct and living species of organisms. ...

A few species, such as Botrydium stoloniferum, are placed incertae sedis, or of uncertain position, as to order in this classification scheme. Genera Ascoseira Ascoseirales is an order in the Phylum Phaeophyta or Brown algae. ... Genera Aglaozonia Zanardini Cutleria Greville Microzonia J Agardh Padinella JE Areschoug Stifftia Nardo Zanardinia Zanardini Cutleriales is an order in the Phylum Phaeophyta or Brown algae. ... Genera Arthrocladia Desmarestia Desmarestiales is an order in the Phylum Phaeophyta or Brown algae. ... Dictyotales is large order in the Phylum Phaeophyta or Brown algae. ... Frans Reinhold Kjellman was a professor of botany at the University of Uppsala in Sweden who specialized in marine phycology. ... Familia Ectocarpaceae C.Agardh Ralfsiaceae Farlow Scytosiphonaceae Farlow Splachnidiaceae Mitchell & Whitting Ectocarpales is a very large order in the Phylum Phaeophyta or Brown algae. ... Genera Ascophyllum Bifurvaria Carpophyllum Coccophora Cystophaera Cystosiera Durvillea Fucus Halidrys Himanthalia Hormosira Pelvetia Pelvetiopsis Phyllospora Sargassum Turbinaria Xaphophora Fucales is an order in the Phylum Phaeophyta or Brown algae. ... Kelp are large seaweeds, belonging to the brown algae and classified in the order Laminariales. ... Genera Carpomitra Sporochnus Sporochnales is an order in the Phylum Phaeophyta or Brown algae. ... Incertae sedis—of uncertain position (seat)—is a term used to define a taxonomic group where its broader relationships are unknown or undefined. ...

Life cycle

The life cycle shows great variability from one group to another. However the life cycle of Laminaria consists of the diploid generation, that is the large plant well know to most people. It produces sporangia from specialised microscioic structures, these divide meiotically (meiosis) before they are released. As they are haploid there are equal numbers of male and female spores.^[1] Diploid (meaning double in Greek) cells have two copies (homologs) of each chromosome (both sex- and non-sex determining chromosomes), usually one from the mother and one from the father. ... Not to be confused with miosis. ... Haploid (meaning simple in Greek) cells have only one copy of each chromosome. ...

Uses

Druehl, L.D. 1988. %. Cultivated edible kelp. "in" Lembi, C.A. and Waaland, J.R. (Editors) Algae and Human Affairs. Cambridge University Press, Cambridge. ISBN 0 521 32115 8.

References

The National University of Ireland (NUI) is a federal university system of constituent universities, previously called constituent colleges, and recognised colleges set up under the Irish Universities Act, 1908, and significantly amended by the Universities Act, 1997. ... December 7 is the 341st day (342nd in leap years) of the year in the Gregorian calendar. ... For the Manfred Mann album, see 2006 (album). ...

External links

Contents

Taxonomy

Life cycle

Uses

References

External links

Further reading

See also

Contents

Taxonomy GA_googleFillSlot("encyclopedia_square");

Life cycle

Uses

References

External links

Further reading

See also

Taxonomy