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Selenium, which is an essential element for animals and prokaryotes and is a beneficial element for many plants, is the least-common of all the elements essential to life. [ 3 ] [ 63 ] Selenium acts as the catalytic center of several antioxidant enzymes, such as glutathione peroxidase , [ 11 ] and plays a wide variety of other biological roles .
The various forms of life are caused by an appropriate mixture of elements. [41] Democritus (460 BC) was an atomist ; he thought that the essential characteristic of life was having a soul ( psyche ), and that the soul, like everything else, was composed of fiery atoms.
[4] [5] Plate tectonics are needed for life over a long time span, and carbon-based life is important in the plate tectonics process. [6] Iron- and sulfur-based Anoxygenic photosynthesis life forms that lived from 3.80 to 3.85 billion years ago on Earth produced an abundance of black shale deposits. These shale deposits increase heat flow and ...
Astronomers have detected more evidence that Saturn’s moon Enceladus may be one of the most promising places to search for life beyond Earth.
Graphic representation of carbon, hydrogen, nitrogen, oxygen, phosphorus, and sulfur. CHNOPS and CHON are mnemonic acronyms for the most common elements in living organisms. . "CHON" stands for carbon, hydrogen, oxygen, and nitrogen, which together make up more than 95 percent of the mass of biological system
Finally, although mineral and elements are in many ways synonymous, minerals are only bioavailable to the extent that they can be absorbed. To be absorbed, minerals either must be soluble or readily extractable by the consuming organism. For example, molybdenum is an essential mineral, but metallic molybdenum has no nutritional benefit.
The first English use of the expression "meaning of life" appears in Thomas Carlyle's Sartor Resartus (1833–1834), book II chapter IX, "The Everlasting Yea". [1]Our Life is compassed round with Necessity; yet is the meaning of Life itself no other than Freedom, than Voluntary Force: thus have we a warfare; in the beginning, especially, a hard-fought battle.
Vitamins and minerals are essential to the proper functioning and maintenance of the human body. [114] There are 20 trace elements and minerals that are essential in small quantities to body function and overall human health. [114] Iron deficiency is the most common inadequate nutrient worldwide, affecting approximately 2 billion people. [115]