WATERFALL SEQUENCE FOR INTRINSIC BLOOD CLOTTING.

A simple waterfall sequence is proposed to explain the function of the various protein clotting factors during the formation of the fibrin clot. When clotting is initiated, each cloting factor except fibrinogen is converted to a form that has enzymatic activity. This activation occurs in a sepwise sequence with each newly formed enzyme reacting with its specific substrate, converting it to an active enzyme.