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Element Per. Gr. Role(s) in nature (non-living and living) Role(s) in technology (old and new) 1: H: Hydrogen 1 1: Astronomy: source of power by nuclear fusion (proton–proton chain reaction and CNO cycle) Biology: One of the most common elements in living organisms: Petrochemical industry: hydrodealkylation, hydrodesulfurization
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.
Over 1.5 million living animal species have been described—of which around 1 million are insects—but it has been estimated there are over 7 million in total. Animals range in size from 8.5 millionths of a metre to 33.6 metres (110 ft) long and have complex interactions with each other and their environments, forming intricate food webs .
The elements of earth, water, air, and fire, were classed as the fundamental building blocks of nature. This system prevailed in the Classical world and was highly influential in medieval natural philosophy. Although Paracelsus uses these foundations and the popular preexisting names of elemental creatures, he is doing so to present new ideas ...
The six aforementioned elements are used by organisms in a variety of ways. Hydrogen and oxygen are found in water and organic molecules, both of which are essential to life. Carbon is found in all organic molecules, whereas nitrogen is an important component of nucleic acids and proteins.
This is a list of minerals which have Wikipedia articles. Minerals are distinguished by various chemical and physical properties. Differences in chemical composition and crystal structure distinguish the various species .
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This is a list of chemical elements and their atomic properties, ordered by atomic number (Z). Since valence electrons are not clearly defined for the d-block and f-block elements, there not being a clear point at which further ionisation becomes unprofitable, a purely formal definition as number of electrons in the outermost shell has been used.