FXIIa plays a very important role in {HEAD ~ the initiation stage} in the intrinsic blood clotting system, {TAIL ~ fibrinolysis system} and plasma kallikrein kinin system 
FXIIa plays a very important role in { HEAD ~ the initiation stage } in the intrinsic blood clotting system , { TAIL ~ fibrinolysis system } and plasma kallikrein kinin system
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH