FACTOID # 21: 15% of Army recruits from South Dakota are Native American, which is roughly the same percentage for female Army recruits in the state.
 
 Home   Encyclopedia   Statistics   States A-Z   Flags   Maps   FAQ   About 
   
 
WHAT'S NEW
 

SEARCH ALL

FACTS & STATISTICS    Advanced view

Search encyclopedia, statistics and forums:

 

 

(* = Graphable)

 

 


Encyclopedia > Green algae
Green algae

Scientific classification
Kingdom: Protista or Plantae
Divisions

Chlorophyta
Charophyta
Image File history File linksMetadata Green_algae. ... For other uses, see Scientific classification (disambiguation). ... Typical phyla Chromalveolata Chromista Heterokontophyta Haptophyta Cryptophyta (cryptomonads) Alveolata Dinoflagellata Apicomplexa Ciliophora (ciliates) Cabozoa Excavata Euglenozoa Percolozoa Metamonada Rhizaria Radiolaria Foraminifera Cercozoa Archaeplastida (in part) Rhodophyta (red algae) Glaucophyta (basal archaeplastids) Amoebozoa Choanozoa Many others; classification varies Protists (IPA: (RP); (GenAm)), Greek protiston -a meaning the (most) first of all... For other uses, see Plant (disambiguation). ... Classes[1] Bryopsidophyceae Chlorophyceae Pedinophyceae Pleurastrophyceae Prasinophyceae Trebouxiophyceae Ulvophyceae Chlorophyta, a division of green algae, includes about 8000 species[2][1] of mostly aquatic photosynthetic eukaryotic organisms. ... Classes Mesostigmatophyceae Chlorokybophyceae Klebsormidiophyceae Zygnemophyceae    Zygnematales    Desmidiales Charophyceae    Coleochaetales    Charales The Charophyta are a division of green algae, including the closest relatives of the embryophyte plants. ...

Green algae are microscopic protists; found in all aquatic environments, including marine, freshwater and brackish water.


The green algae (singular: green alga) are the large group of algae from which the embryophytes (higher plants) emerged. As such, they form a paraphyletic group, variously included among the Plantae or with the Protista. The green algae include unicellular and colonial flagellates, usually but not always with two flagella per cell, as well as various colonial, coccoid, and filamentous forms. In the Charales, the closest relatives of higher plants, full differentiation of tissues occurs. There are about 6000 species of green algae. [1] Many species live most of their lives as single-cells, other species form colonies or long filaments. A seaweed (Laurencia) up close: the branches are multicellular and only about 1 mm thick. ... Divisions Non-vascular land plants (bryophytes) Marchantiophyta - liverworts Anthocerotophyta - hornworts Bryophyta - mosses †Horneophytopsida Vascular plants (tracheophytes) †Rhyniophyta—rhyniophytes †Zosterophyllophyta—zosterophylls Lycopodiophyta—clubmosses †Trimerophytophyta—trimerophytes Pteridophyta - ferns and horsetails Ophioglossophyta - adders-tongues Seed plants (spermatophytes) †Pteridospermatophyta - seed ferns Pinophyta - conifers Cycadophyta - cycads Ginkgophyta - ginkgo Gnetophyta - gnetae Magnoliophyta - flowering plants The embryophytes... Paraphyletic - Wikipedia /**/ @import /skins-1. ... Divisions Green algae land plants (embryophytes) non-vascular embryophytes Hepatophyta - liverworts Anthocerophyta - hornworts Bryophyta - mosses vascular plants (tracheophytes) seedless vascular plants Lycopodiophyta - clubmosses Equisetophyta - horsetails Pteridophyta - true ferns Psilotophyta - whisk ferns Ophioglossophyta - adderstongue ferns seed plants (spermatophytes) †Pteridospermatophyta - seed ferns Pinophyta - conifers Cycadophyta - cycads Ginkgophyta - ginkgo Gnetophyta - gnetae Magnoliophyta... Typical phyla Chromalveolata Chromista Heterokontophyta Haptophyta Cryptophyta (cryptomonads) Alveolata Dinoflagellata Apicomplexa Ciliophora (ciliates) Cabozoa Excavata Euglenozoa Percolozoa Metamonada Rhizaria Radiolaria Foraminifera Cercozoa Archaeplastida (in part) Rhodophyta (red algae) Glaucophyta (basal archaeplastids) Amoebozoa Choanozoa Many others; classification varies Protists (IPA: (RP); (GenAm)), Greek protiston -a meaning the (most) first of all... Flagellata from Ernst Haeckels Artforms of Nature, 1904 Parasitic excavate (Giardia lamblia) Green alga (Chlamydomonas) Flagellates are cells with one or more whip-like organelles called flagella. ... For the insect anatomical structure, see Antenna (biology). ... Genera Chara Lamprothamnium Nitella Tolypella The Charales are an order of green algae, and are believed to be the closest relatives of the embryophyte plants. ...


A few other organisms rely on green algae to conduct photosynthesis for them. The chloroplasts in euglenids and chlorarachniophytes were presumably acquired from ingested green algae, and in the latter retain a vestigial nucleus (nucleomorph). Some species of green algae, particularly of genera Trebouxia or Pseudotrebouxia (Trebouxiophyceae), can be found in symbiotic associations with fungi to form lichens. In general the fungal species that partner in lichens cannot live on their own, while the algal species is often found living in nature without the fungus. Major groups Phototrophs    Euglenales    Eutreptiales Osmotrophs    Rhabdomonadales Phagotrophs    ?Heteronematales    ?Sphenomonadales The euglenids (also spelled euglenoids) are one of the best-known groups of flagellates, commonly found in freshwater especially when it is rich in organic materials, with a few marine and endosymbiotic members. ... Genera Chlorarachnion Gymnochlora Lotharella Cryptochlora Chlorarachniophytes are a small group of algae occasionally found in tropical oceans. ... Species uncultured Trebouxia photobiont uncultured Trebouxia (Asterochloris) photobiont In taxonomy, Trebouxia is a genus of algae, specifically of the Microthamniales. ... Divisions Chytridiomycota Zygomycota Ascomycota Basidiomycota The Fungi (singular: fungus) are a large group of organisms ranked as a kingdom within the Domain Eukaryota. ... For other uses, see Lichen (disambiguation). ...

Contents

Cellular structure

Almost all forms have chloroplasts. These contain chlorophylls a and b, giving them a bright green colour (as well as the accessory pigments beta carotene and xanthophylls),[2] and have stacked thylakoids.[3] Chlorophyll is a green pigment found in most plants, algae, and cyanobacteria. ... Beta-carotene is a form of carotene with β-rings at both ends. ... This article or section does not cite its references or sources. ... Thylakoids (green) inside a chloroplast Thylakoids (green) inside a cyanobacterium (Synechocystis) A Thylakoid is a membrane-bound compartment inside chloroplasts and cyanobacteria. ...


All green algae have mitochondria with flat cristae. When present, flagella are typically anchored by a cross-shaped system of microtubules, but these are absent among the higher plants and charophytes. Flagella are used to move the organism. Green algae usually have cell walls containing cellulose, and undergo open mitosis without centrioles. Electron micrograph of a mitochondrion showing its mitochondrial matrix and membranes In cell biology, a mitochondrion (plural mitochondria) is a membrane-enclosed organelle that is found in most eukaryotic cells. ... For the insect anatomical structure, see Antenna (biology). ... Microtubules are one of the components of the cytoskeleton. ... Cellulose as polymer of β-D-glucose Cellulose in 3D Cellulose (C6H10O5)n is a polysaccharide of beta-glucose. ... Mitosis divides genetic information during cell division. ... A centriole in biology is a hollow cylindrical organelle found in most animal cells, and cells of fungi and algae though not frequently in plants. ...


Origins

The chloroplasts of green algae are bound by a double membrane, so presumably they were acquired by direct endosymbiosis of cyanobacteria. A number of cyanobacteria show similar pigmentation, but this appears to have arisen more than once, and the chloroplasts of green algae are no longer considered closely related to such forms. Instead, the green algae probably share a common origin with the red algae. It has been suggested that Proto-mitochondrion be merged into this article or section. ... Orders The taxonomy is currently under revision. ... Possible classes Florideophyceae Bangiophyceae Cyanidiophyceae The red algae (Rhodophyta, IPA: , from Greek: (rhodon) = rose + (phyton) = plant, thus red plant) are a large group, about 5,000–6,000 species [1] of mostly multicellular, marine algae, including many notable seaweeds. ...


Classification

Green algae are often classified with their embryophyte descendants in the green plant clade Viridiplantae (or Chlorobionta). Viridiplantae, together with red algae and glaucophyte algae, form the supergroup Primoplantae, also known as Archaeplastida or Plantae sensu lato. A clade is a term belonging to the discipline of cladistics. ... Viridiplantae (literally green plants) are a clade comprising the green algae and embryophyte plants. ... There are very few or no other articles that link to this one. ... The glaucophytes, also referred to as glaucocystophytes or glaucocystids, are a tiny group of freshwater algae. ... subgroups Glaucophyta Rhodophyta (Red algae) Viridiplantae (green plants) (= Chlorobionta) Green algae (grade group) Embryophyta (Land plants) Primoplantae is a group of organisms that includes green plants (green algae and land plants), red algae, and an obscure group of single-celled algae called the glaucophytes. ... The Archaeplastida are a major line of eukaryotes, comprising the land plants, green and red algae, and a small group called the glaucophytes. ...

A growth of the green seaweed, Enteromorpha on rock substratum at the ocean shore. Some green seaweeds, such as Enteromorpha and Ulva, are quick to utilize inorganic nutrients from land runoff, and thus can be indicators of nutrient pollution.
A growth of the green seaweed, Enteromorpha on rock substratum at the ocean shore. Some green seaweeds, such as Enteromorpha and Ulva, are quick to utilize inorganic nutrients from land runoff, and thus can be indicators of nutrient pollution.

The orders outside the Chlorophyta are often grouped as the division Charophyta, which is paraphyletic to higher plants, together comprising the Streptophyta. Sometimes the Charophyta is restricted to the Charales, and a division Gamophyta is introduced for the Zygnematales and Desmidiales. In older systems the Chlorophyta may be taken to include all the green algae, but taken as above they appear to form a monophyletic group. Download high resolution version (980x735, 193 KB)Photo of green algal growth (Enteromorpha sp. ... Download high resolution version (980x735, 193 KB)Photo of green algal growth (Enteromorpha sp. ... Species Ulva lactuca Ulva pertusa Ulva fasciata Ulva rigida Ulva pertusa Ulva linza and more at algaeBASE The sea lettuces comprise the genus Ulva, a group of edible green algae widely distributed along the coasts of the worlds oceans. ... A nutrient is either a chemical element or compound used in an organisms metabolism or physiology. ... Classes[1] Bryopsidophyceae Chlorophyceae Pedinophyceae Pleurastrophyceae Prasinophyceae Trebouxiophyceae Ulvophyceae Chlorophyta, a division of green algae, includes about 8000 species[2][1] of mostly aquatic photosynthetic eukaryotic organisms. ... Orders see text The Chlorophyceae are one of the classes of green algae, distinguished mainly on the basis of ultrastructural morphology. ... Orders Acrosiphoniales Caulerpales Cladophorales Dasycladales Oltmansiellopsidales Trentepohliales Ulotrichales Ulvales The Ulvophyceae or Ulvophytes are class of green algae, distinguished mainly on the basis of ultrastructural morphology. ... Orders Chlorellales Ctenocladales Microthamniales Prasiolales In taxonomy, the Trebouxiophyceae are a class of the Chlorophyta. ... Families Mesotaeniaceae Zygnemataceae The Zygnematales are an order of green algae, comprising several thousand different species in genera such as the well-known Zygnema and Spirogyra. ... Families Closteriaceae Desmidiaceae Gonatozygaceae Peniaceae Desmids are an order (Desmidiales) of green algae, comprising around 40 genera and 5,000 species[1], found mostly but not exclusively in fresh water. ... Genera Chara Lamprothamnium Nitella Tolypella The Charales are an order of green algae, and are believed to be the closest relatives of the embryophyte plants. ... Classes Mesostigmatophyceae Chlorokybophyceae Klebsormidiophyceae Zygnemophyceae    Zygnematales    Desmidiales Charophyceae    Coleochaetales    Charales The Charophyta are a division of green algae, including the closest relatives of the embryophyte plants. ... Paraphyletic - Wikipedia /**/ @import /skins-1. ...

Green Algae conjugating
Green Algae conjugating

Image File history File linksMetadata Size of this preview: 643 × 600 pixel Image in higher resolution (954 × 890 pixel, file size: 112 KB, MIME type: image/jpeg) I took this image using a digital camera and a compound light microscope at a total magnification of 100X. This is fresh water... Image File history File linksMetadata Size of this preview: 643 × 600 pixel Image in higher resolution (954 × 890 pixel, file size: 112 KB, MIME type: image/jpeg) I took this image using a digital camera and a compound light microscope at a total magnification of 100X. This is fresh water...

Reproduction

Green algae are eukaryotic organisms that follow a reproduction cycle called alternation of generations. Sporic or diplohaplontic life cycle. ...


Sexual reproduction varies from fusion of identical cells (isogamy) to fertilization of a large non-motile cell by a smaller motile one (oogamy). However, these traits show some variation, most notably among the basal green algae, called prasinophytes. This article is about fertilisation in animals and plants. ...


Haploid algae cells (containing only one copy of their DNA) can fuse with other haploid cells to form diploid zygotes. When filamentous algae do this, they form bridges between cells, and leave empty cell walls behind that can be easily distinguished under the light microscope. This process is called conjugation.


The species of Ulva are reproductively isomorphic, the diploid vegetative phase is the site of meiosis and releases haploid zoospores which germinate and grow producing a haploid phase alternating with the vegetative phase. [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. ... For the figure of speech, see meiosis (figure of speech). ...


References

  1. ^ Thomas, D. 2002. Seaweeds. The Natural History Museum, London. ISBN 0 565 09175 1
  2. ^ Burrows 1991. Seaweeds of the British Isles. Volume 2 Natural History Museum, London. ISBN 0 565 00981 8
  3. ^ Hoek, C. van den, Mann, D.G. and Jahns, H.M. 1995. Algae An introduction to phycology. Cambridge University Press, Cambridge. ISBN 0 521 30419 9
  • Lewis, L. A & R. M. McCourt (2004). Green algae and the origin of land plants 91 (10): 1535–1556. 
  • Green algae and cyanobacteria in lichens

See also


  Results from FactBites:
 
alga: Definition and Much More from Answers.com (5841 words)
Algae were formerly classified into three major groups-the red, brown, and green seaweeds-based on the pigment molecules in their chloroplasts.
The pond scum, a green slime found in stagnant water, is a green alga, as is the green film found on the bark of trees.
Algae, the major food of fish (and thus indirectly of many other animals), are a keystone in the aquatic food chain of life; they are the primary producers of the food that provides the energy to power the whole system.
  More results at FactBites »

 
 

COMMENTARY     


Share your thoughts, questions and commentary here
Your name
Your comments

Want to know more?
Search encyclopedia, statistics and forums:

 


Press Releases |  Feeds | Contact
The Wikipedia article included on this page is licensed under the GFDL.
Images may be subject to relevant owners' copyright.
All other elements are (c) copyright NationMaster.com 2003-5. All Rights Reserved.
Usage implies agreement with terms, 1022, m