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Ecology: the Biology of Interactions. 2.15. (Supplement) Venus, Earth, Mars
We can only rejoice that, situated between “frozen” Mars and “feverish” Venus, our native Earth provides quite suitable conditions for life.
Ecology: biology of interaction. 2.14. (supplement) Some stages of the history of life on Earth
The oxygen revolution was the most significant turning point in Earth's history. Not only the composition of the atmosphere changed, but also the composition of rocks forming on Earth's surface. …
Ecology: The Biology of Interactions. 2.13. (Supplement) The Geochronological Scale
To describe the history of life on Earth, one needs a scale that allows the relevant spans of time to be described. How is this history studied? By the sequence …
Ecology: The Biology of Interactions. 2.12. (Supplement) The Origin of Life. Preliving Systems
For the origin of life, three conditions are necessary and sufficient. These are: the possibility of a full spectrum of transitional states between nonliving and living systems; the possibility of …
Ecology: The Biology of Interactions. 2.11. (Supplement) What Is Life?
Life is the maintenance and reproduction of characteristic highly ordered structures, a process that is improved in the course of evolution and carried out in accordance with an internal program …
Ecology: The Biology of Interactions. 2.10. (Supplement) The Evolution of the Universe, the Solar System, and the Earth
The age of the Earth, and of the Solar System, is 4.6 billion years. The Sun and planets formed from a gas-dust cloud produced by the destruction of preceding stars. …
Ecology: The Biology of Interactions. 2.09. The Biogeochemical Cycle of Phosphorus
The BGC cycle of phosphorus is regulated much less effectively than the carbon and nitrogen cycles considered above, because phosphorus lacks an exchange pool in the atmosphere. Phosphorus is the …
Ecology: the Biology of Interactions. 2.08. The Biogeochemical Cycle of Sulfur
Sulfur is a fairly abundant element in the Earth’s crust (fifteenth in chemical abundance), occurring in various oxidation states. It is an essential component of proteins. Sulfur is consumed (by …
Ecology: the Biology of Interactions. 2.07. The Biogeochemical Cycle of Nitrogen
The BGC cycle of nitrogen is more complex than that of carbon. It is also extremely important for living organisms. Although the atmosphere contains more nitrogen than other elements, incorporating …
Ecology: the Biology of Interactions. 2.06. The Biogeochemical Cycle of Carbon
Naturally, discussion of the characteristics of the biogeochemical cycles of several key elements should begin with carbon. Carbon is the basis of organic compounds, and therefore the carbon cycle is …
Ecology: the Biology of Interactions. 2.05. Energy Sources for BGC Cycles
The movement of elements in the biosphere is sustained by three main energy sources (“drive belts” for BGC cycles): solar energy transformed by the hydrosphere and atmosphere in the hydrological …
Ecology: biology of interaction. 2.04. Biogeochemical cycles
Terrestrial life is built on a highly complex chemical foundation. Its existence requires many chemical elements. Although the main compound in organisms is water, organic substances composed of diverse atoms …