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The important sulfur cycle is a biogeochemical cycle in which the sulfur moves between rocks, waterways and living systems. It is important in geology as it affects many minerals and in life because sulfur is an essential element (), being a constituent of many proteins and cofactors, and sulfur compounds can be used as oxidants or reductants in microbial respiration. [1]
Iron–sulfur world hypothesis. The iron–sulfur world hypothesis is a set of proposals for the origin of life and the early evolution of life advanced in a series of articles between 1988 and 1992 by Günter Wächtershäuser, a Munich patent lawyer with a degree in chemistry, who had been encouraged and supported by philosopher Karl R. Popper ...
The history of Earth is divided into four great eons, starting 4,540 mya with the formation of the planet. Each eon saw the most significant changes in Earth's composition, climate and life. Each eon is subsequently divided into eras, which in turn are divided into periods, which are further divided into epochs. Eon.
Sulfur is an essential component of all living cells. It is the eighth most abundant element in the human body by weight, [100] about equal in abundance to potassium, and slightly greater than sodium and chlorine. [101] A 70 kg (150 lb) human body contains about 140 grams (4.9 oz) of sulfur. [102]
A biogeochemical cycle, or more generally a cycle of matter, [ 1 ] is the movement and transformation of chemical elements and compounds between living organisms, the atmosphere, and the Earth's crust. Major biogeochemical cycles include the carbon cycle, the nitrogen cycle and the water cycle. In each cycle, the chemical element or molecule is ...
Geological cycles. Age of the Earth – Aluminum cycle – Arsenic cycle – Boron cycle – Bromine cycle – Cadmium cycle – Calcium cycle – Carbonate–silicate cycle – Chlorine cycle – Chromium cycle – Climate change – Copper cycle – Cycle of erosion – Dynamic topography – Dynamic topography – Earthquake cycle ...
The δ 34 S value, recorded by sulfate in marine evaporites, can be used to chart the sulfur cycle throughout earth's history. [ 7 ] [ 4 ] The Great Oxygenation Event around 2,400 million years ago altered the sulfur cycle radically, as increased atmospheric oxygen permitted an increase in the mechanisms that could fractionate sulfur isotopes ...
Sulfur metabolism. Sulfur is metabolized by all organisms, from bacteria and archaea to plants and animals. Sulfur can have an oxidation state from -2 to +6 and is reduced or oxidized by a diverse range of organisms. [1] The element is present in proteins, sulfate esters of polysaccharides, steroids, phenols, and sulfur-containing coenzymes.