Protists diatoms

Microplankton 20 to 200 jjum Protists Phytoplankton Radiolarians, foraminiferans Diatoms, raphidophytes, Phaeocystis ... 

Protists Eukaryotic microorganisms that are neither animal, fungi, plant, or archaean. Unicellular forms include the amoeboid protozoans and algae, such as the foraminferans and radiolarians, and dinoflagellates and diatoms, respectively. Some algae are either multicellular or colonial, such as the red algae and freshwater Volvox, respectively. 

Even species that are not known to produce bioactive metabolites may have a large environmental impact, such as Emiliania huxeleyi. This haptomonad protist blooms periodically in the Bering Sea at the detriment of diatoms, disruptii the food chain with massive death of migratory birds and fish losses. Mnemiopsis leidyi is another major such problem this comb jelly has invaded the Black Sea, subtracting zooplankton to fish. 

Alkaline pH pH 13, Plectonema pH 10.5, Natrobacterium pH 9-11, Methanosarcinales at Lost City hydrothermal vent environment pH 10, many species of protists and rotifers (e.g., Lake Nakuru, Africa) diatoms (e.g., Mono Lake) Soda lakes peridotite-hosted hydrothermal systems (e.g., Lost City)... 

The colonization of two Phaeocystis species (Prymnesiophyceae) by pennate diatoms and other protists a significant contribution to colony biomass... 

The coexistence of Phaeocystis species with pennate diatoms and other protists, although not universally observed, is a well-known and common phenomenon (Hasle 1964 Rousseau et al. 1994 Hasle and Syvertsen 1997 Peperzak etal. 1998 Wassmann et al. 1999 Throndsen et al. 2003 Hamm and Rousseau 2003). In general, the colonization of... 

Menden-Deuer S, Lessard EJ (2000) Carbon to volume relationships for dinoflagellates, diatoms and other protist plankton. Limnol Oceanogr 45 569-579... 

The second most important mineral phase of the biological pump is biogenic opal, Si02. Opal shells are produced by diatoms, a marine alga, and by radiolarians, a heterotrophic protist. On a large scale, production of Si02 is limited by the availability of dissolved sihca, in the form of silicic acid, H4Si04. 

The diatoms, radiolaria, and sponges that control the silica concentration of seawater at a very low level (<1 ppm at the surface to 10-15 ppm in some bottom water) are relatively recent evolutionary newcomers. Sihceous sponges and protists with what were probably siliceous scales appeared in the Neoproterozoic (Gehling and Rigby, 1996 Brasier et al., 1997 ... 

Smetacek V. (1999) Diatoms and the ocean carbon cycle. Protist 150, 25-32. 

Protists are larger, more complex single-celled organisms than bacteria. Many of the autotrophic protists are key producers in the intertidal environments while some of the heterotrophic forms are important consumers. Diatoms and ciliates are two common types of coastal protists. 

As in many protists, reproduction in diatoms is by binary fission, an asexual method in which the parent cell divides into two identical cells. Asexual reproduction involves only one parent, and the two offspring are clones, or exact duplicates of the parent. During fission, a diatom cell experiences challenges that cells of other species of protists do not face it also has to divide its frustule. 

Barron, J. A. 1993. Diatoms. In LiPPS, J. E. (ed.) Fossil Prokaryotes and Protists. Blackwell Scientific Ehibli-cations, Oxford, 155—167. 

Kiihn, S.F. (1997). Victoriniella multiformis, gen. et spec. nov. (incerta sedis), a polymorphic parasitoid protist infecting the marine diatom... 

Amato, A., Kooistra, W.H., Ghiron, J.H. et al. (2007). Reproductive isolation among sympatric cryptic species in marine diatoms. Protist 158,193-207. 

Wilhelm C, Buchel C, Fisahn J, et al The regulation of carbon and nutrient assimilation in diatoms is significandy different from green algae, Protist 157 91—124, 2006. 

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