Post-transition metal traditionally used for tools.' In modern use, the term 'semimetal' sometimes refers, loosely or explicitly, to metals with incomplete metallic character in crystalline structure, electrical conductivity or electronic structure. Examples include gallium, ytterbium, bismuth, mercury and neptunium. Metalloids, which are in-between elements that are neither metals nor nonmetals, are also sometimes instead called semimetals. The elements commonly recognised as metalloids are boron, silicon, germanium, arsenic, antimony and tellurium. In old chemistry, before the publication in 1789 of Lavoisier's 'revolutionary' "Elementary Treatise on Chemistry", a semimetal was a metallic element with 'very imperfect ductility and malleability' such as zinc, mercury or
Period 5 element diverse functions of the remainder of the enzymes, molybdenum is a required element for life in higher organisms (eukaryotes), though not in all bacteria. Technetium, ruthenium, rhodium, palladium, silver, tin, and antimony have no biological role. Although cadmium has no known biological role in higher organisms, a cadmium-dependent carbonic anhydrase has been found in marine diatoms. Indium has no biological role and can be toxic as well as Antimony. Tellurium has no biological role, although fungi can incorporate it in place of sulfur and selenium into amino acids such as tellurocysteine and telluromethionine. In humans, tellurium is partly metabolized into