Coagulation | The Intrinsic Pathway of Coagulation

The video tutorial explains the roles of high molecular weight kininogen and bradykinin in inflammation and vessel injury. It details the activation of the intrinsic pathway, highlighting the role of von Willebrand factor and platelets in clotting. The function of polyphosphate kinase in activating factor 12 is discussed, followed by an explanation of the coagulation cascade and the common pathway leading to thrombin formation. The importance of the extrinsic pathway in effective clotting is emphasized, with a comparison to the intrinsic pathway.

What is the role of high molecular weight kininogen in the intrinsic pathway?

• It acts as a cofactor for factor 12 activation.

• It directly activates factor 11.

• It is responsible for the production of thrombin.

• It binds to collagen to initiate platelet adhesion.

How does von Willebrand factor contribute to platelet adhesion?

• By activating factor 12.

• By converting fibrinogen to fibrin.

• By binding to collagen and then to platelets.

• By binding directly to platelets.

What is the function of polyphosphate kinase in platelets?

• It binds calcium ions.

• It polymerizes phosphates to form polyphosphate.

• It activates factor 11.

• It converts fibrinogen to fibrin.

What is required for the activation of factor 12?

• Direct contact with factor 11.

• Conversion of prothrombin to thrombin.

• Binding to a positively charged surface.

• Presence of high molecular weight kininogen.

Which factor is activated by factor 12A in the cascade?

• Factor 11

• Factor 8

• Factor 10

• Factor 9

What is the role of calcium in the activation of factor 9?

• It acts as a cofactor for factor 8.

• It converts fibrinogen to fibrin.

• It directly activates factor 10.

• It binds to negatively charged phospholipids.

What marks the beginning of the common pathway in coagulation?

• Binding of von Willebrand factor to collagen

• Conversion of fibrinogen to fibrin

• Activation of factor 10

• Activation of factor 8

What is the ultimate goal of both intrinsic and extrinsic pathways?

• Activation of factor 12

• Conversion of prothrombin to thrombin

• Binding of platelets to collagen

• Production of bradykinin

Why is the extrinsic pathway considered more crucial than the intrinsic pathway?

• It is responsible for platelet adhesion.

• It produces von Willebrand factor.

• It activates factor 12 directly.

• It is the first pathway to be activated and is essential for effective clotting.

What is the significance of von Willebrand factor in coagulation?

• It binds platelets to the site of vessel injury.

• It activates factor 11.

• It converts prothrombin to thrombin.

• It is a cofactor for factor 12.