Seaweed-covered rocks in the UK

Biologists, specifically marine biologists, consider seaweed to be any of a large number of marine benthic algae that are multicellular, macrothallic, and thus differentiated from most algae that tend to be microscopic in size ^[1]. Many phycologists prefer the term "marine macroalgae" over "seaweeds". Seaweeds are classified into brown (Phaeophyta), red (Rhodophyta) and green algae (Chlorophyta) based on their pigment composition. There are a few species of cyanobacteria however, that may also be categorized as seaweeds. Seaweeds are not to be confused either with plants like seagrasses (which are vascular plants), or actual weeds in the sense of nuisance blooms or accumulations of unwanted species — certainly, seaweeds are natural components of pristine marine ecosystems. (The best definition of "weed" is "A plant in the wrong place"). Seeweed covered rocks. ... Seeweed covered rocks. ... A biologist is a scientist devoted to and producing results in biology through the study of organisms. ... Marine biology is the study of animal and plant life within saltwater ecosystems. ... The worlds oceans as seen from the South Pacific Ocean Oceans (from Okeanos in Greek, the ancient Greeks noticing the strong current that flowed off Gibraltar and assuming it was a great river) cover almost three quarters (71%) of the surface of the Earth, and nearly half of the... In oceanography, marine geology and biology, benthos are the organisms and habitats of the sea floor; in freshwater biology they are the organisms and habitats of the bottoms of lakes, rivers, and creeks. ... A seaweed (Laurencia) up close: the branches are multicellular and only about 1 mm thick. ... Multicellular organisms are those organisms containing more than one cell, and having differentiated cells that perform specialized functions. ... A microscope (Greek: micron = small and scopos = aim) is an instrument for viewing objects that are too small to be seen by the naked or unaided eye. ... Marine is an umbrella term for things relating to the ocean, as with Marine biology, Marine geology, and as a term for a navy, etc. ... Orders Ascoseirales Chordariales Cutleriales Desmarestiales Dictyosiphonales Dictyotales Ectocarpales Fucales Laminariales(kelps) Scytosiphonales Scytothamnales Sphacelariales Sporochnales Syringodermatales Tilopteridales The brown algae or phaeophytes are a large group of multicellular algae, including many notable seaweeds. ... Orders Dictyotales Desmerestiales Fucales Laminariales (kelps) etc. ... Possible classes Florideophyceae Bangiophyceae Cyanidiophyceae Red algae (Rhodophyta, pronounced /ˈrəʊdÉ™(ÊŠ)ËŒfʌɪtÉ™/) are a large group of mostly multicellular, marine algae, including many notable seaweeds. ... Red algae Classes Florideophyceae Bangiophyceae Cyanidiophyceae The red algae are a large group of mostly multicellular, marine algae, including many notable seaweeds. ... Divisions Chlorophyta Charophyta Streptophytina (Subdivision) The green algae are the large group of algae from which the embryophytes (higher plants) emerged. ... A seaweed (Laurencia) up close: the branches are multicellular and only about 1 mm thick. ... Classes Chlorophyceae Ulvophyceae Trebouxiophyceae Prasinophyceae The Chlorophyta sensu stricto or chlorophytes, comprises most of what are commonly called green algae and includes most members of the grade of putatively ancestral scaly flagellates in Prasinophyceae plus members of Ulvophyceae, Trebouxiophyceae, Chlorophyceae, Pedinophyceae, Picocystophyceae, and unclassified Chlorophyta. ... Orders The taxonomy of the Cyanobacteria is currently under revision. ... Johnsons seagrass in Florida coast Seagrass (or sea-grass in British English) is a term that refers to flowering plants from two plant families (Potamogetonaceae and Hydrocharitacea) that grow in the marine environment. ... Divisions Non-seed-bearing plants Equisetophyta Lycopodiophyta Psilotophyta Pteridophyta Superdivision Spermatophyta Pinophyta Cycadophyta Ginkgophyta Gnetophyta Magnoliophyta The vascular plants are plants in the Kingdom Plantae (also called Viridiplantae) that have specialized tissues for conducting water. ...

History

There was a time when a book on the study of seaweeds would have been the reverse of popular. In the early 19th century they were treated with disdain by some: There was a time when a student who, having collected some beautiful algae on the shore, showed the contents of his vasculum to the Professor of Botany, expressing a wish to get some information respecting them. The Professor looked at them, and putting on his spectacles, again looked at them, when, pushing them from him, he exclaimed: "Pooh! a parcel of Seaweeds, Sir; a parcel of Seaweeds!" (Landsborough, D. 1857. A Popular History of British Seaweeds)

Structure

The top of a kelp forest in Otago, New Zealand

Seaweeds may have an appearance that resembles non-arboreal terrestrial plants. Download high resolution version (1296x972, 528 KB)Kelp forest, Otago peninsular, Oct 2004 Author: User:Velela. ... Download high resolution version (1296x972, 528 KB)Kelp forest, Otago peninsular, Oct 2004 Author: User:Velela. ... Kelp Forest Kelp forests are a type of marine ecosystem established around colonies of kelp; they contain rich biodiversity. ... Otago (help· info) is one of the regions of New Zealand and lies in the south-east of the South Island. ... This article is about the biological organisms known as trees. ... Divisions Green algae Chlorophyta Charophyta Land plants (embryophytes) Non-vascular plants (bryophytes) Marchantiophyta - liverworts Anthocerotophyta - hornworts Bryophyta - mosses Vascular plants (tracheophytes) Lycopodiophyta - clubmosses Equisetophyta - horsetails Pteridophyta - true ferns Psilotophyta - whisk ferns Ophioglossophyta - adderstongues Seed plants (spermatophytes) †Pteridospermatophyta - seed ferns Pinophyta - conifers Cycadophyta - cycads Ginkgophyta - ginkgo Gnetophyta - gnetae Magnoliophyta - flowering plants...

• thallus: the algal body
  • lamina: a flattened structure that is somewhat leaf-like
    • sorus: spore cluster
    • on Fucus -- Air bladders: float-assist organ (on blade)
    • on kelp -- floats: float-assist organ (in between lamina and stipe)
  • stipe: a stem-like structure, may be absent
  • holdfast: specialized basal structure providing attachment to a surface, often a rock or another alga.

The stipe and blade are collectively known as frond. Thallus is an undifferentiated vegetative tissue (without specialization of function) of some non-mobile organisms, which were previously known as the thallophytes. ... A Lamina in the algae is a generally flattened structure which typically forms the principal bulk of macroscopic plants. ... The underside of a fertile frond of Dicksonia antarctica. ... Spores produced in a sporic life cycle. ... Species F. serratus F. vesiculosus Fucus is a genus of seaweed that lives in the intertidal zones of rocky shores. ... There are several meanings of float: an air-filled vessel that floats on water, such as some types of lifeboats buoyancy float (project management) floating currency floating exchange rate floating point, a datatype in computer science free float of company stock insurance (investable policyholder funds) root beer float: ice cream... Families Alariaceae Chordaceae Laminariaceae Lessoniaceae Phyllariaceae Pseudochordaceae Kelp are large seaweeds, belonging to the brown algae and classified in the order Laminariales. ... There are several meanings of float: an air-filled vessel that floats on water, such as some types of lifeboats buoyancy float (project management) floating currency floating exchange rate floating point, a datatype in computer science free float of company stock insurance (investable policyholder funds) root beer float: ice cream... In botany, a stipe is a stem type of structure. ... A holdfast is a rootlike plant structure that anchors a seaweed. ... In botany, a stipe is a stem type of structure. ... A fern with simple (lobed or pinnatifid) blades, the dissection of each blade not quite reaching to the rachis. ...

Ecology

References

Lewis, J.R. 1964. The Ecology of Rocky Shores. The English Universities Press Ltd.

Uses

Seaweeds are extensively used as food by coastal peoples, particularly in Japan and Korea, but also in China, Vietnam, Indonesia, Peru, Taiwan, the Canadian Maritimes, Scandinavia, Ireland, Wales, Philippines, and Scotland, among other places. For example, Porphyra is a red alga used in Wales to make laverbread, and in Japan dried, formed into sheets called nori which is widely used in soups, and for wrapping sushi, boiled rice stuffed with bits of raw fish, sea urchin roe, or other ingredients. Chondrus crispus (commonly known as Irish moss or Carrageen Moss) is another red alga used in producing various food additives, along with Kappaphycus and various gigartinoid seaweeds. Korea (Korean: (ì¡°ì„  or 한국, see below) is a geographic area, civilization, and former state situated on the Korean Peninsula in East Asia. ... The Maritimes or Maritime provinces are a region of Canada on the Atlantic coast, consisting of New Brunswick, Nova Scotia and Prince Edward Island. ... Scandinavia is a region in Northern Europe named after the Scandinavian Peninsula. ... Motto: (Welsh for Wales for ever) Anthem: Hen Wlad Fy Nhadau Capital Cardiff Largest city Cardiff Official language(s) English, Welsh Government Constitutional monarchy  - Queen Queen Elizabeth II  - Prime Minister Tony Blair MP  - First Minister Rhodri Morgan AM Unification    - by Gruffudd ap Llywelyn 1056  Area    - Total 20,779 km² (3rd... Motto: (Latin for No one provokes me with impunity)1 Anthem: Multiple unofficial anthems Capital Edinburgh Largest city Glasgow Official language(s) English, Gaelic, Scots2 Government Constitutional monarchy  - Queen Queen Elizabeth II  - Prime Minister Tony Blair MP  - First Minister Jack McConnell MSP Unification    - by Kenneth I 843  Area    - Total 78... Porphyra is a genus of red algae. ... Laverbread (Welsh: Bara Lawr) is a traditional Welsh delicacy. ... Nori (æµ·è‹”) is a Japanese term used to refer to edible varieties of seaweed in the various species of the red alga Porphyra, including most notably and . ... In Japanese cuisine, sushi (Japanese: ) is a food made of vinegared rice combined with various toppings or fillings. ... Binomial name Chondrus crispus Stackhouse Irish moss, or carrageen moss (Irish carraigín, moss of the rock) is a species of red algae (Chondrus crispus) which grows abundantly along the rocky parts of the Atlantic coast of Europe and North America. ... Binomial name Chondrus crispus Stackhouse Irish moss, or carrageen moss (Irish carraigín, moss of the rock) is a species of red algae (Chondrus crispus) which grows abundantly along the rocky parts of the Atlantic coast of Europe and North America. ...

Seaweeds are also harvested or cultivated for the extraction of Alginate, Agar and Carrageenan, collectively known as hydrocolloids or phycocolloids. Hydrocolloids have attained commercial significance because they are used in various industries, the most common being food production^[2]. Agar is found in foods such as confectionary, meats and poultry products, desserts and beverages and moulded foods. Carrageenan is used in preparation of salad dressings and sauces, dietetic foods, and as a preservative in meat and fish products, dairy items and baked goods. Alginates enjoy many of the same uses as carrageenan, but are also used in production of industrial products such as paper coatings, adhesives, dyes, gels, explosives and in processes such as paper sizing, textile printing, hydro-mulching and drilling. The food industry exploits the gelling, water-retention, emulsifying and other physical properties of these hydrocolloids. In the biomedicine and pharmaceutical industries, alginates are used in wound dressings, and production of dental moulds and have a host of other applications. In microbiology research, agar is extensively used as culture medium. Carrageenans, alginates and agaroses (the latter are prepared from agar by purification), together with other lesser-known macroalgal polysaccharides, also have several important biological activities or applications in biomedicine. For instance, it has been demonstrated in laboratory studies that seaweeds may have curative properties for tuberculosis, arthritis, colds and influenza, and worm infestations. [1] Alginate is a linear copolymer with homopolymeric blocks of (1-4)-linked ß-D-mannuronate (M) and its C-5 epimer α-L-guluronate (G) residues, respectively, covalently linked together in different sequences or blocks. ... This article or section does not cite its references or sources. ... Carrageenan (pronounced ) is a family of linear sulphated polysaccharides extracted from red seaweeds. ... Hydrocolloids are used in some skin care products A hydrocolloid is defined as a colloid system were the colloid particles are disperesed in water. ... An agar plate streaked with microorganisms Microbiology is the study of microorganisms, which are unicellular or cell-cluster microscopic organisms. ... It has been suggested that Antituberculant be merged into this article or section. ... this is a very painful thing my name is lauren!!!!! haha muaha muaha muahaha Arthritis (from Greek arthro-, joint + -itis, inflammation; plural: arthritides) is a group of conditions where there is damage caused to the joints of the body. ... my mum died of influenza. ...

A number of research studies have been conducted to investigate claims of seaweed's effects on human health. [2]

Other seaweeds may be used as seaweed fertiliser. Seaweed fertiliser is valuable addition to the organic garden, and is abundantly available for free for those living near the coast. ...

Knotted wrack, a type of seaweed, on an exposed tidal shore-line

Image File history File linksMetadata Download high-resolution version (1944x2592, 2828 KB) Summary Ascophylum nodosum on inter-tidal zone of Menai Strait. ... Image File history File linksMetadata Download high-resolution version (1944x2592, 2828 KB) Summary Ascophylum nodosum on inter-tidal zone of Menai Strait. ... Binomial name Ascophyllum nodosum (L.) Le Jolis Knotted wrack (Ascophyllum nodosum (Linnaeus) Le Jolis) is a large, common, brown, edible seaweed of the northern Atlantic Ocean. ...

References

1. ^ Smith, G.M. 1944. Marine Algae of the Monterey Peninsula, California. Stanford Univ., 2nd Edition.
2. ^ Round F.E. 1962 The Biology of the Algae. Edward Arnold Ltd.

External links

• The Seaweed Site, information on all aspects of seaweeds and marine algal biology
• AlgaeBase, a searchable taxonomic, image, and utilization database of freshwater, marine and terrestrial algae, including seaweeds. The database is searched 10,000 times a day.
• SeaweedAfrica, information on seaweed utilisation
• NCBI PubMed Search , allows for search on health research studies, including seaweed
• Seaweed Research Links, Many useful seaweed research links