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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] Although over 500 amino acids exist in nature, by far the most important are the 22 α-amino acids incorporated into proteins.[2] Only these 22 appear in the genetic code of life.[3 ...
A protein is a polyamide. Secondary structure: regularly repeating local structures stabilized by hydrogen bonds. The most common examples are the α-helix, β-sheet and turns. Because secondary structures are local, many regions of different secondary structure can be present in the same protein molecule.
Umami (/ uː ˈ m ɑː m i / from Japanese: 旨味 Japanese pronunciation:), or savoriness, is one of the five basic tastes. It has been described as savory and is characteristic of broths and cooked meats.: 35–36 People taste umami through taste receptors that typically respond to glutamates and nucleotides, which are widely present in meat broths and fermented products.
In a DNA double helix, each type of nucleobase on one strand bonds with just one type of nucleobase on the other strand. This is called complementary base pairing.Purines form hydrogen bonds to pyrimidines, with adenine bonding only to thymine in two hydrogen bonds, and cytosine bonding only to guanine in three hydrogen bonds. . This arrangement of two nucleotides binding together across the ...
Anning, depicted with her dog. Mary Anning (21 May 1799 – 9 March 1847) was an English fossil collector and palaeontologist. She made discoveries of Jurassic marine fossil beds in the cliffs along the English Channel at Lyme Regis, which changed the scientific thinking about prehistoric life and the history of the Earth.
List of chemical elements. 118 chemical elements have been identified and named officially by IUPAC. A chemical element, often simply called an element, is a type of atom which has a specific number of protons in its atomic nucleus (i.e., a specific atomic number, or Z ). [1]
American retail corporation Walmart has been the world's largest company by revenue since 2014. [1] The list is limited to the largest 50 companies, all of which have annual revenues exceeding US$130 billion. This list is incomplete, as not all companies disclose their information to the media and/or general public. [3]
