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Polysiphonia Nigra
''Polysiphonia nigra'' is a species of marine alga in the division Rhodophyta. Description ''Polysiphonia nigra'' is a relatively small red algae which grows to a height of 20 or 30 cm. It consists of tufts of branched axes. The branches are cylindrical and erect, consisting of large axial cells forming about one third of the diameter of the branch, surrounded by periaxial cells in a collar around the axis, each cell of the same length, generally 9 - 13 in number. Cortication absent. Attached by rhizoids.Maggs, C.A. 1993. ''Seaweeds of the British Isles Volume 1 Rhodophyta Part 3A Ceramiales'' The Natural History Museum, LondonBunker, F.StPD., Maggs, C.A.Brodie, J.A., Bunker, A.R. 2017. ''Seaweeds of Britain and Ireland.'' Second Edition. Wild Nature Press. Plymouth, UK. Reproduction The plants are dioecious with spermatrangial branchlets borne near the apices of the branches. Cystocarps are globular with a small ostiole. Tetrasporangia are arranged in short lateral branch ...
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Alga
Algae ( , ; : alga ) are any of a large and diverse group of photosynthetic, eukaryotic organisms. The name is an informal term for a polyphyletic grouping that includes species from multiple distinct clades. Included organisms range from unicellular microalgae, such as '' Chlorella'', '' Prototheca'' and the diatoms, to multicellular forms, such as the giant kelp, a large brown alga which may grow up to in length. Most are aquatic and lack many of the distinct cell and tissue types, such as stomata, xylem and phloem that are found in land plants. The largest and most complex marine algae are called seaweeds, while the most complex freshwater forms are the '' Charophyta'', a division of green algae which includes, for example, '' Spirogyra'' and stoneworts. Algae that are carried by water are plankton, specifically phytoplankton. Algae constitute a polyphyletic group since they do not include a common ancestor, and although their plastids seem to have a single or ...
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Rhodophyta
Red algae, or Rhodophyta (, ; ), are one of the oldest groups of eukaryotic algae. The Rhodophyta also comprises one of the largest phyla of algae, containing over 7,000 currently recognized species with taxonomic revisions ongoing. The majority of species (6,793) are found in the Florideophyceae ( class), and mostly consist of multicellular, marine algae, including many notable seaweeds. Red algae are abundant in marine habitats but relatively rare in freshwaters. Approximately 5% of red algae species occur in freshwater environments, with greater concentrations found in warmer areas. Except for two coastal cave dwelling species in the asexual class Cyanidiophyceae, there are no terrestrial species, which may be due to an evolutionary bottleneck in which the last common ancestor lost about 25% of its core genes and much of its evolutionary plasticity. The red algae form a distinct group characterized by having eukaryotic cells without flagella and centrioles, chloroplasts th ...
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Cystocarp
A cystocarp is the fruiting structure produced in the red algae after fertilization, especially such a structure having a special protective envelope (as in '' Polysiphonia)''. The structure from which carpospores are released.Maggs, C.A. and Hommersand, M.H. 1993. ''Seaweeds of the British Isles Volume 1 Rhodophyta Part 3A Ceramiales.'' The Natural History Museum, London References {{reflist Algal anatomy ...
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British Isles
The British Isles are a group of islands in the North Atlantic Ocean off the north-western coast of continental Europe, consisting of the islands of Great Britain, Ireland, the Isle of Man, the Inner and Outer Hebrides, the Northern Isles (Orkney and Shetland), and over six thousand smaller islands. They have a total area of and a combined population of almost 72 million, and include two sovereign states, the Republic of Ireland (which covers roughly five-sixths of Ireland), and the United Kingdom of Great Britain and Northern Ireland. The Channel Islands, off the north coast of France, are normally taken to be part of the British Isles, even though geographically they do not form part of the archipelago. Under the UK Interpretation Act 1978, the Channel Islands are clarified as forming part of the British Islands, not to be confused with the British Isles. The oldest rocks are 2.7 billion years old and are found in Ireland, Wales and the north-west of Scotland. Du ...
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Europe
Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a subcontinent of Eurasia and it is located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. Comprising the westernmost peninsulas of Eurasia, it shares the continental landmass of Afro-Eurasia with both Africa and Asia. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south and Asia to the east. Europe is commonly considered to be separated from Asia by the watershed of the Ural Mountains, the Ural River, the Caspian Sea, the Greater Caucasus, the Black Sea and the waterways of the Turkish Straits. "Europe" (pp. 68–69); "Asia" (pp. 90–91): "A commonly accepted division between Asia and Europe ... is formed by the Ural Mountains, Ural River, Caspian Sea, Caucasus Mountains, and the Blac ...
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Norway
Norway, officially the Kingdom of Norway, is a Nordic country in Northern Europe, the mainland territory of which comprises the western and northernmost portion of the Scandinavian Peninsula. The remote Arctic island of Jan Mayen and the archipelago of Svalbard also form part of Norway. Bouvet Island, located in the Subantarctic, is a dependency of Norway; it also lays claims to the Antarctic territories of Peter I Island and Queen Maud Land. The capital and largest city in Norway is Oslo. Norway has a total area of and had a population of 5,425,270 in January 2022. The country shares a long eastern border with Sweden at a length of . It is bordered by Finland and Russia to the northeast and the Skagerrak strait to the south, on the other side of which are Denmark and the United Kingdom. Norway has an extensive coastline, facing the North Atlantic Ocean and the Barents Sea. The maritime influence dominates Norway's climate, with mild lowland temperatures on the ...
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Portugal
Portugal, officially the Portuguese Republic, In recognized minority languages of Portugal: :* mwl, República Pertuesa is a country located on the Iberian Peninsula, in Southwestern Europe, and whose territory also includes the Macaronesian archipelagos of the Azores and Madeira. It features the westernmost point in continental Europe, its mainland west and south border with the North Atlantic Ocean and in the north and east, the Portugal-Spain border, constitutes the longest uninterrupted border-line in the European Union. Its archipelagos form two autonomous regions with their own regional governments. On the mainland, Alentejo region occupies the biggest area but is one of the least densely populated regions of Europe. Lisbon is the capital and largest city by population, being also the main spot for tourists alongside Porto, the Algarve and Madeira. One of the oldest countries in Europe, its territory has been continuously settled and fought over since prehistoric tim ...
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Newfoundland
Newfoundland and Labrador (; french: Terre-Neuve-et-Labrador; frequently abbreviated as NL) is the easternmost province of Canada, in the country's Atlantic region. The province comprises the island of Newfoundland and the continental region of Labrador, having a total size of 405,212 square kilometres (156,500 sq mi). In 2021, the population of Newfoundland and Labrador was estimated to be 521,758. The island of Newfoundland (and its smaller neighbouring islands) is home to around 94 per cent of the province's population, with more than half residing in the Avalon Peninsula. Labrador borders the province of Quebec, and the French overseas collectivity of Saint Pierre and Miquelon lies about 20 km west of the Burin Peninsula. According to the 2016 census, 97.0 per cent of residents reported English as their native language, making Newfoundland and Labrador Canada's most linguistically homogeneous province. A majority of the population is descended from English and Irish ...
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New Jersey
New Jersey is a U.S. state, state in the Mid-Atlantic States, Mid-Atlantic and Northeastern United States, Northeastern regions of the United States. It is bordered on the north and east by the state of New York (state), New York; on the east, southeast, and south by the Atlantic Ocean; on the west by the Delaware River and Pennsylvania; and on the southwest by Delaware Bay and the state of Delaware. At , New Jersey is the List of U.S. states and territories by area, fifth-smallest state in land area; but with close to 9.3 million residents, it ranks List of U.S. states and territories by population, 11th in population and List of U.S. states and territories by population density, first in population density. The state capital is Trenton, New Jersey, Trenton, and the most populous city is Newark, New Jersey, Newark. With the exception of Warren County, New Jersey, Warren County, all of the state's 21 counties lie within the combined statistical areas of New York City or Delaw ...
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