Lists of metalloids Lists of metalloids This is a list of sources that each list metalloids: elements classified as metalloids. The sources are listed in chronological order. Lists of metalloids differ since there is no rigorous definition of metalloid (or its occasional alias, 'semi-metal'). Individual lists share common ground, with variations occurring at the margins. The elements most often regarded as metalloids are boron, silicon, germanium, arsenic, antimony and tellurium. Wikipedia generally categorises these six as metalloids, with the addition of astatine. Other sources may subtract from this list or add a varying number of other elements. This table show which elements are
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