翻訳と辞書 Words near each other ・ Die Entlassung ・ Die Entscheidung des Tilman Riemenschneider ・ Didymopleella ・ Didymoplexiella ・ Didymoplexiopsis ・ Didymoplexis ・ Didymopogon ・ Didymops ・ Didymos ・ Didymosalpinx ・ Didymosphaerella ・ Didymosphaeria ・ Didymosphaeria arachidicola ・ Didymosphaeria taiwanensis ・ Didymosphaeriaceae ・ Didymosphenia geminata ・ Didymosporangium ・ Didymostoma ・ Didymostoma aurotinctalis ・ Didymostoma euphranoralis ・ Didymoteicho ・ Didymothallus ・ Didymuria violescens ・ Didymus ・ Didymus Chalcenterus ・ Didymus Mutasa ・ Didymus the Blind ・ Didymus the Musician ・ Didynamipus sjostedti ・ Didyoyeri Dictionary Lists mini英和辞書 mini和英辞書 Webster 1913 Latin-English FOLDOC Wikipedia English ウィキペディア

翻訳と辞書　辞書検索 [ 開発暫定版 ] スポンサード リンク Didymosphenia geminata ： ウィキペディア英語版 Didymosphenia geminata ''Didymosphenia geminata'', commonly known as didymo or rock snot, is a species of diatom that produces nuisance growths in freshwater rivers and streams with consistently cold water temperatures and low nutrient levels. It is native to the northern hemisphere, and considered an invasive species in Australia, Argentina, New Zealand, and Chile.〔(【引用サイトリンク】title=Alto al Didymo )〕 Even within its native range, it has taken on invasive characteristics since the 1980s.〔 It is not considered a significant human health risk,〔(【引用サイトリンク】title=FAQs related to Didymo )〕 but it can affect stream habitats and sources of food for fish and make recreational activities unpleasant. This microscopic alga can be spread in a single drop of water.〔 ==Description== ''Didymosphenia geminata'' is a diatom, which is a type of single-celled organism unique for their silica (SiO2) cell walls. The life history of diatoms includes both vegetative and sexual reproduction, though the sexual stage is not yet documented in this species. Although it is symmetric only along the apical axis, typical of gomphonemoid diatoms, it is a cymbelloid, which are typically symmetric along both primary axes. Cells contain a raphe, which allows them to move on surfaces, and an apical porefield, through which a mucopolysaccharide stalk is secreted. The stalk can attach to rocks, plants, or other submerged surfaces. When the diatom cell divides, through vegetative reproduction, the stalk divides too, eventually forming a mass of branching stalks. The nuisance build-up is not the cell itself, but their massive production of extracellular stalks. Extracellular polymeric substances (EPS) that form the stalks are made primarily of polysaccharides and protein, forming complex, multi-layered structures that are resistant to degradation.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Didymosphenia geminata」の詳細全文を読む スポンサード リンク 翻訳と辞書 : 翻訳のためのインターネットリソース Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.