Blood clotting and haemostasis

Key point

Key events (interacting simultaneously)

Platelet plug phases

Platelet secretion

Clotting cascade

Key points

Sequential activation of inactive pro-enzymes to active enzymes that catalyse further reactions
Amplifies signal
End product is fibrin generated from fibrinogen
Clotting pro-enzymes synthesised in liver (except VWF)
Initiating event is tissue factor from endothelial injury activating extrinsic pathway

Components and activation

Intrinsic pathway
Extrinsic pathway
Common pathway

Clot control and lysis