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The main elements that comprise the human body (including water) can be summarized as CHNOPS . About 99% of the mass of the human body is made up of six elements: oxygen, carbon, hydrogen, nitrogen, calcium, and phosphorus. Only about 0.85% is composed of another five elements: potassium, sulfur, sodium, chlorine, and magnesium.
Carbon compounds. Carbon compounds are defined as chemical substances containing carbon. [ 1][ 2] More compounds of carbon exist than any other chemical element except for hydrogen. Organic carbon compounds are far more numerous than inorganic carbon compounds. In general bonds of carbon with other elements are covalent bonds.
Carbon-based compounds form the basis of all known life on Earth, and the carbon-nitrogen-oxygen cycle provides a small portion of the energy produced by the Sun, and most of the energy in larger stars (e.g. Sirius). Although it forms an extraordinary variety of compounds, most forms of carbon are comparatively unreactive under normal conditions.
In a 2018 study, carbon was found to compose approximately 550 billion tons of all life on Earth. [ 16][ 17] It is the second most abundant element in the human body by mass (about 18.5%) after oxygen. [ 18] The most important characteristics of carbon as a basis for the chemistry of cellular life are that each carbon atom is capable of forming ...
A heterotroph ( / ˈhɛtərəˌtroʊf, - ˌtrɒf /; [ 1][ 2] from Ancient Greek ἕτερος (héteros) 'other' and τροφή (trophḗ) 'nutrition') is an organism that cannot produce its own food, instead taking nutrition from other sources of organic carbon, mainly plant or animal matter. In the food chain, heterotrophs are primary ...
This article is about the class of chemicals. For the structures and properties of the standard proteinogenic amino acids, see Proteinogenic amino acid. Structure of a typical L -alpha-amino acid in the "neutral" form. Amino acids are organic compounds that contain both amino and carboxylic acid functional groups. [ 1 ]
Sterols and related compounds play essential roles in the physiology of eukaryotic organisms, and are essential for normal physiology of plants, animals, and fungi. [4] For example, cholesterol forms part of the cellular membrane in animals, where it affects the cell membrane's fluidity and serves as secondary messenger in developmental signaling.
In the context of nutrition, a mineral is a chemical element. Some "minerals" are essential for life, but most are not. [ 1][ 2][ 3] Minerals are one of the four groups of essential nutrients; the others are vitamins, essential fatty acids, and essential amino acids. [ 4] The five major minerals in the human body are calcium, phosphorus ...