brown algae

brown algae
pl.n.
any of a class (Phaeophyceae, division Chromophycota) of large, photosynthetic, marine thallophytic algae, including kelp and fucus, having a brown pigment that obscures the green color of chlorophyll

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▪ alga class
      members of the class Phaeophyceae (division Chromophyta), comprising about 1,500 species, common in cold waters along continental coasts. Freshwater species are rare. Species colour varies from dark brown to olive green, depending upon the proportion of brown pigment (fucoxanthin) to green pigment (chlorophyll). Some brown seaweeds have gas-filled bladders (pneumatocysts), which keep photosynthetic parts of the algal thallus floating on or near the surface of the water. Brown algae vary in form and size from small filamentous epiphytes (Ectocarpus) to complex giant kelps (kelp) that range in size from 1 metre to more than 100 metres (3.3 to 330 feet; Laminaria, Macrocystis, Nerocystis). Rockweed, another type of brown algae, is found attached to rocky coasts in temperate zones (Fucus, Ascophyllum) or floating freely (Sargassum). Brown algae multiply by asexual and sexual reproduction; both the motile zoospores and gametes have two unequal flagella. Once a major source of iodine and potash, brown algae are still an important source of algin, a colloidal gel used as a stabilizer in the baking and ice-cream industries. Certain species are also used as fertilizer, and several are eaten as a vegetable (e.g., Laminaria, called kombu in Japan) in East Asia. Brown algae of the order Laminariales are popularly called kelps.

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Universalium. 2010.

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Look at other dictionaries:

  • Brown algae — Temporal range: 150–0 Ma[1][2] …   Wikipedia

  • brown algae — pl.n. any of a class (Phaeophyceae, division Chromophycota) of large, photosynthetic, marine thallophytic algae, including kelp and fucus, having a brown pigment that obscures the green color of chlorophyll …   English World dictionary

  • brown algae — rudadumbliai statusas T sritis ekologija ir aplinkotyra apibrėžtis Daugialąsčiai dumbliai (Phaeophyta), augantys prisitvirtinę prie dugno, povandeninių uolų, kriauklių, kitų dumblių (skiriama brown algae1500 rūšių). Paplitę šaltosiose šiaurės… …   Ekologijos terminų aiškinamasis žodynas

  • brown algae — brown′ al′gae n. pl. mcr any marine algae of the class Phaeophyceae, having brown pigments in addition to chlorophyll • Etymology: 1900–05 …   From formal English to slang

  • brown algae — noun algae having the chlorophyll masked by brown and yellow pigments • Hypernyms: ↑alga, ↑algae • Hyponyms: ↑kelp, ↑fucoid, ↑fucoid algae, ↑rockweed, ↑serrated wrack, ↑ …   Useful english dictionary

  • brown algae — /braʊn ˈældʒi/ (say brown aljee) noun algae belonging to the division Phaeophyta, usually brown as a result of brown pigments added to their chlorophyll …  

  • brown algae — plural noun a large group of algae that are typically olive brown or greenish in colour, including many seaweeds. [Class Phaeophyceae.] …   English new terms dictionary

  • brown algae — Phaeophyta …   Medical dictionary

  • golden-brown algae — gold′en brown al′gae n. pl. mcr a group of mostly marine, gold to yellow brown algae of the phylum Chlorophyta, containing the pigments chlorophyll, carotene, and xanthophyll • Etymology: 1955–60 …   From formal English to slang

  • brown seaweeds — brown algae or brown seaweeds plural noun The Phaeophyceae, one of the main divisions of the algae • • • Main Entry: ↑brown brown seaweeds see ↑brown algae above. • • • Main Entry: ↑brown …   Useful english dictionary

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