Metal Biology: Aspects of Beneficial Effects
| Autor: | Ulf Lindh |
|---|---|
| Rok vydání: | 2007 |
| Předmět: |
Dose-Response Relationship
Drug Ecology Iron Geography Planning and Development Krypton Trace element chemistry.chemical_element General Medicine Basis (universal algebra) Trace Elements Astrobiology Metal Toxicology Trace (semiology) Selenium Zinc chemistry visual_art visual_art.visual_art_medium Humans Environmental Chemistry Analytical chemist Beneficial effects Iodine |
| Zdroj: | AMBIO: A Journal of the Human Environment. 36:107-110 |
| ISSN: | 0044-7447 |
| DOI: | 10.1579/0044-7447(2007)36[107:mbaobe]2.0.co;2 |
| Popis: | The biology of metals is not a new concept. It may be expressed as trace element biology, which in a sense is a broader concept. Nevertheless, in this presentation we also include nonmetals in metal biology. Trace elements are often described as mineralsfrom a fundamental point a misconception. Depending on the platform from which trace elements are defined we find different approaches. An analytical chemist would probably define them as elements appearing in concentrations below 100 mg kg-'. If a biologist is asked, you would most certainly be presented with an exclusion definition. We start with excluding the major elements of life: hydrogen, carbon, nitrogen, and oxygen. In the next phase the minor elements sodium, magnesium, potassium, and calcium as well as phosphorus, sulfur, and chlorine are excluded. In addition, the noble gases helium, neon, argon, krypton, xenon, and radon are excluded for obvious reasons. At the end of this process, we have excluded 17 of the elements. The number of naturally occurring elements is disputed but here we will assume that they are 90. Seventy-three of these elements are defined as trace elements. The fascinating aspect of these two different approaches in defining trace element is that both sides arrive at about the same elements, at least with occurrence in living systems as a basis. There are further distinctions among trace elements that have to be accounted for. Not all 73 elements are essential for life. Significant unanimity is reached for 14 or 15 elements. |
| Databáze: | OpenAIRE |
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