<Tr> <Th> MeSH </Th> <Td> D014812 </Td> </Tr> <Tr> <Td_colspan="2"> In Wikidata </Td> </Tr> <P> Vitamin K is a group of structurally similar, fat - soluble vitamins that the human body requires for complete synthesis of certain proteins that are prerequisites for blood coagulation (K from Koagulation, Danish for "coagulation") and which the body also needs for controlling binding of calcium in bones and other tissues . The vitamin K - related modification of the proteins allows them to bind calcium ions, which they cannot do otherwise . Without vitamin K, blood coagulation is seriously impaired, and uncontrolled bleeding occurs . Preliminary clinical research indicates that deficiency of vitamin K may weaken bones, potentially leading to osteoporosis, and may promote calcification of arteries and other soft tissues . </P> <P> Chemically, the vitamin K family comprises 2 - methyl - 1, 4 - naphthoquinone (3 -) derivatives . Vitamin K includes two natural vitamers: vitamin K and vitamin K. Vitamin K, in turn, consists of a number of related chemical subtypes, with differing lengths of carbon side chains made of isoprenoid groups of atoms . </P>

What is the function of vitamin k in coagulation