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A representation of the 3D structure of the protein myoglobin showing turquoise α-helices. This protein was the first to have its structure solved by X-ray crystallography. Toward the right-center among the coils, a prosthetic group called a heme group (shown in gray) with a bound oxygen molecule (red). Proteins are large biomolecules and ...
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 ...
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.
Google Translate is a web-based free-to-user translation service developed by Google in April 2006. [11] It translates multiple forms of texts and media such as words, phrases and webpages. Originally, Google Translate was released as a statistical machine translation service. [11] The input text had to be translated into English first before ...
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]
Worldwide distribution of country calling codes. Regions are coloured by first digit. Country calling codes, country dial-in codes, international subscriber dialing (ISD) codes, or most commonly, telephone country codes are telephone number prefixes for reaching telephone subscribers in foreign countries or areas via international telecommunication networks.
NATO in 2024 NATO (North Atlantic Treaty Organization) is an international military alliance consisting of 32 member states from Europe and North America.It was established at the signing of the North Atlantic Treaty on 4 April 1949.Article 5 of the treaty states that if an armed attack occurs against one of the member states, it shall be considered an attack against all members, and other ...
