HEMA 2: SECONDARY HEMOSTASIS (nelly's reviewer)

• What is a plasma factor?

  Coagulation factor found in plasma
• What is a platelet factor?

  Coagulation factor found in platelets
• What is a zymogen?

  Inactive form of an enzyme
• What is a serine protease?

  Active enzyme hydrolyzing specific peptide bonds
• What does a small "a" indicate in coagulation factors?

  Indicates an activated coagulation factor
• What is a cascade in the context of coagulation?

  Series of activation events in coagulation
• What is a fibrin clot?

  End stage of coagulation process
• Why is a fibrin clot considered unstable?

  It can dissolve before stabilization occurs
• What is the goal of secondary hemostasis?

  To form a stable fibrin clot
• What are the two pathways involved in secondary hemostasis?

  • Extrinsic pathway
  • Intrinsic pathway
• What are enzyme precursors in coagulation factors?

  Zymogens like II, VII, IX, X, XI, XII
• What are non-enzymatic cofactors in coagulation?

  Factors V, VIII, HMWK, Tissue Factors
• What is the role of calcium in coagulation?

  Acts as a bridge for clotting factors
• How does phospholipid trigger coagulation?

  By being exposed during vessel injury
• What happens on vessel injury in coagulation?

  Plasma proteins, tissue factors, and calcium interact
• What is the International Committee on Nomenclature of Blood Coagulation Factors responsible for?

  Assigning Roman numerals to plasma factors
• Why is Factor III never deficient?

  It is produced by tissue
• What is the significance of Factor VII's half-life?

  It is the shortest and reduces early in liver dysfunction
• What does prothrombin time assess?

  It assesses liver function in acute settings
• What is the relationship between Factor VIII and vWF?

  Factor VIII requires vWF for stability
• What is the common characteristic of coagulation factors?

  Deficiency leads to bleeding, except some factors
• What are the comments on coagulation factors I to IV?

  • Factor I: Fibrinogen, most concentrated
  • Factor II: Prothrombin, low concentration
  • Factor III: Tissue Factor, never deficient
  • Factor IV: Calcium Ions, essential for coagulation
• What is the significance of Factor V Leiden?

  It leads to excessive clot formation
• What is the role of Factor VIII in hemophilia A?

  Deficiency of Factor VIII causes hemophilia A
• What is the function of Factor XIII?

  Stabilizes the clot
• How is Factor XIII deficiency detected?

  Using the 5M Urea Clot Solubility Test
• What is the role of serine proteases in coagulation?

  They hydrolyze peptide bonds in substrates
• What is the purpose of the thrombin feedback mechanism?

  Controls and balances coagulation process
• What is the role of thrombin in coagulation?

  It acts as an autocatalytic activator
• What are the roles of thrombin in the coagulation process?

  1. Activator in positive feedback loop
  2. Autocatalytic, enhances prothrombinase effect
  3. Triggers series of reactions to produce itself
• What does the enzyme do to peptide bonds?

  It hydrolyzes peptide bonds.
• What are the roles of Tissue Factor and other contact factors in coagulation?

  • Tissue Factor: cofactor for Factor VII
  • Factor V: cofactor for Factor X
  • Factor VIII: cofactor for Factor IX
  • HMWK: cofactor for PK
• How do cofactors affect serine proteases?

  Cofactors increase stability and reactivity.
• What is the purpose of the coagulation process?

  • Controls coagulation
  • Balances clotting and bleeding
• What are the two roles of thrombin in the feedback mechanism?

  1. Activator (Positive Feedback Loop)
  2. Inhibitor (Negative Feedback Loop)
• What is the role of thrombin as an activator?

  It forms clots through autocatalysis.
• What does thrombin enhance in the coagulation process?

  It enhances the prothrombinase complex.
• What does thrombin activate in the coagulation cascade?

  It activates Factors V and VIII.
• What happens when thrombin concentration increases?

  It destroys Factors V and VII.
• What is the role of Protein C in coagulation?

  It acts as a potent anticoagulant.