Please read the following article: Whitman, W.B., Coleman, D.C.,


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Please read the following article: Whitman, W.B., Coleman, D.C., and Wiebe, W.J. (1998). Prokaryotes: The unseen majority. Proceedings of the National Academy of Sciences 95(2): 6578-6583. Note: You can find the above article in your iBoard course under Homework Assignment Instructions. Write a three to five page paper in which you summarize and reflect on this very important article that was one of the first to point out the magnitude of nutrients stored in microorganisms. The paper must be in proper APA format, have a references section, and site at least 2 peer reviewed articles. Please use AAU’s LIRN Library to search for these articles. You may utilize the Academic Resource Center (ARC) for a concise guide on how to use LIRN and for APA formatting guidelines. ATTACHMENT PREVIEW Download attachment 6 pages prokaryotes read.pdf Proc. Natl. Acad. Sci. USA Vol. 95, pp. 6578–6583, June 1998 Perspective Prokaryotes: The unseen majority William B. Whitman*†, David C. Coleman‡, and William J. Wiebe§ Departments of *Microbiology, ‡Ecology, and §Marine Sciences, University of Georgia, Athens GA 30602 portion of these cells are the autotrophic marine cyanobacteria and Prochlorococcus spp., which have an average cellular density of 4 ϫ 104 cells͞ml (6). The deep (Ͼ200 m) oceanic water contains 5 ϫ 104 cells͞ml on average. From global estimates of volume, the upper 200 m of the ocean contains a total of 3.6 ϫ 1028 cells, of which 2.9 ϫ 1027 cells are autotrophs, whereas ocean water below 200 m contains 6.5 ϫ 1028 cells (Table 1). The upper 10 cm of sediment in the open ocean is included in the oceanic habitat because, as a result of animal mixing and precipitation, it is essentially contiguous with the overlying water column. Most of the marine sediment is found in the continental rise and abyssal plain, so the numbers of prokaryotes were calculated from an arithmetic average of the cellular densities in the studies cited by Deming and Baross (ref. 9; Table 1). The Nova Scotian continental rise was excluded from this calculation because of its unusual hydrology (10). There are fewer estimates of the number of prokaryotes in freshwaters and saline lakes (5). Given an average density of 106 cells͞ml, the total number of cells in freshwaters and saline lakes is 2.3 ϫ 1026. This value is three orders of magnitude below the numbers of prokaryotes in seawater. In the polar regions, a relatively dense community of algae and prokaryotes forms at the water–ice interface in annual sea ice (11). In Antarctic sea ice, the estimated number of prokaryotes (2.2 ϫ 1024 cells) was based on the mean cell numbers of Delille and Rosiers (12) and the mean areal extent of seasonal ice (13). If the population size in the Arctic is similar (14), the global estimate for both polar regions is 4 ϫ 1024 cells, only a fraction of the total number of prokaryotes. Soil. Soil is a major reservoir of organic carbon on earth and an important habitat for prokaryotes. Prokaryotes are an essential component of the soil decomposition subsystem, in which plant and animal residues are degraded into organic matter and nutrients are released into food webs (15). Many studies indicate that the number of prokaryotes in forest soils is much less than the number in other soils. The total number of prokaryotes in forest soil was estimated from detailed direct counts from a coniferous forest ultisol (16), which were considered representative of forest soils in general (Table 2). For other soils, including grasslands and cultivated soils, the numbers of prokaryotes appear about the same, e.g., the number of prokaryotes in Negev desert soil is comparable to the number in cultivated soil (19). Therefore, the numbers of prokaryotes in all other soils were estimated from the unpublished field studies of E. A. Paul for cultivated soils (cited in ref. 18). Subsurface. The subsurface is defined here as terrestrial habitats below 8 m and marine sediments below 10 cm. Few direct enumerations

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