Biological organisation

Plant water status is affected by environmental pollution and consequently influences plant function at every level of biological organisation. It can be characterized by measurements of the relative water content (RWC), the water deficit, the water potential ( P ) and the osmotic potential ( Fq), along with transpiration rate and stomatal resistance. Since for the latter four parameters, tissue samples are removed from the plant, they are usually determined in the end of an experiment. If several sampling times are needed, then additional plants/replicates must be included. 

One of us (A. R.) wishes to thank the European Molecular Biology Organisation for a grant which enabled him to take part in this work. This work was supported by the Medical Research Council, England. 

Morowitz, H.J. Energy flow in biology. In Biological Organisation as a Problem in Thermal Physics, OxBow Press Woodbridge, CT, 1979. 

Wicke, E., and Onken, H. U., in "From Chemical to Biological Organisation (M. Markus, S. C., Muller, andG. Nicolis, eds.), p.68. Springer-Verlag, Heidelberg, 1988. 

Table 2.1 Types of responses measurable at different levels of biological organisation.

Level of biological organisation Types of measurable responses... 

Variability in toxicity measurements is recognised at every level of biological organisation, from the subcellular (Ratner and Fairbrother, 1991) to the community level (Taub el al., 1989). Differences in the response of individuals to pollutants may be due to environmental or genetic factors or a combination of the two (Hoffmann and Parsons, 1991). The total variability in the response of an organism to a chemical (Vp) can be represented by the equation ... 

Couillard, Y., Campbell, P.G.C., Pellerin-Massicotte, J. and Auclair, J.C. (1995) Field transplantation of a freshwater bivalve, Pyganodon grandis, across a metal contamination gradient. II. Metallothionein response to Cd and Zn exposure, and links to effects at higher levels of biological organisation. Can. J. Fish. Aquat. Sci., 52, 703-715. 

Brooks, D., Explanation of homoplasy at different levels of biological organisation, in Homoplasy. The Recurrence of Similarity in Evolution, Sanderson, M.J. and Hufford, L., Eds., Academic Press, San Diego, CA, 1996, pp. 3-36. 

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