It is necessary for the synthesis of prothrombin and several other coagulation factors.  
Given to newborns to prevent hemorraghic disease, one form is synthesized by bacteria in the human colon.  Another form consists of several napthoquinone compounds found in the leaves of plants, including alfalfa, where it was isolated in 1939.  It is necessary for the synthesis of prothrombin and several other coagulation factors.  FTP, name this fat-soluble vitamin whose deficiency impairs blood clotting.
Given to newborns to prevent hemorraghic disease, one form is synthesized by bacteria in the human colon.  
Vitamin K