2.1 General Mechanism

• How many important substances affect blood coagulation?

  More than 50
• What are pro-coagulants?

  Substances that promote coagulation
• What are anticoagulants?

  Substances that inhibit coagulation
• What determines whether blood will coagulate?

  The balance between pro-coagulants and anticoagulants
• What predominates in the bloodstream to prevent coagulation?

  Anticoagulants
• What happens when a blood vessel is ruptured?

  Pro-coagulants become activated and override anticoagulants
• How many essential steps are there in the clotting process?

  Three essential steps
• What are the three essential steps of clotting?

  1. Formation of prothrombin activator
  2. Conversion of prothrombin into thrombin
  3. Conversion of fibrinogen into fibrin fibers
• What initiates the clotting process?

  Rupture of the vessel or damage to blood
• What is prothrombin activator?

  A complex of activated substances
• What does prothrombin activator catalyze?

  Conversion of prothrombin into thrombin
• What role does thrombin play in clot formation?

  It converts fibrinogen into fibrin fibers
• What do fibrin fibers do in the clot?

  They enmesh platelets, blood cells, and plasma
• What will be discussed after the mechanism of clot formation?

  The initiating stages of prothrombin activator formation