Ch.16

Hemostasis has three major steps. The first is vasoconstriction and the final step is coagulation. What occurs between these two steps? A. Formation of a platelet plug B. Exposure of collagen C. Contraction of vascular smooth muscle D. Formation of a fibrin protein mesh to form a clot

A. Formation of a platelet plug

The extrinsic pathway of coagulation is activated by the A. activation of a proenzyme exposed to collagen. B. sticking of platelets to damaged tissue. C. release of tissue factor by a damaged endothelium. D. conversion of prothrombin to thrombin. E. release of heparin from the liver.

C. release of tissue factor by a damaged endothelium.

Which are the two anticoagulants produced by the body? A. antithrombin III and heparin B. antithrombin III and plasmin C. protacyclin and heparin D. heparin and plasmin E. tissue plasminogen activator and plasmin

A. antithrombin III and heparin

The common pathway of coagulation begins with the A. release of tissue factor by a damaged endothelium. B. activating of a clotting factor that converts prothrombin to thrombin. C. activation of a clotting factor that converts fibrinogen to fibrin. D. activation of a proenzyme exposed to collagen. E. sticking of platelets to damaged tissue.

B. activating of a clotting factor that converts prothrombin to thrombin.

The intrinsic pathway of coagulation is activated by the A. release of heparin from the liver. B. activation due to exposed to collagen. C. conversion of prothrombin to thrombin. D. sticking of platelets to damaged tissue. E. release of tissue factor by a damaged endothelium.

B. activation due to exposed to collagen.

At each step in the coagulation cascade, something causes an inactive precursor to become activated, which in turn causes activation of the next protein. Other than the final fibrin product, which type of molecule is each of these activated proteins? A. Structural protein B. Integrin C. Energy molecule D. Enzyme

D. Enzyme

The process of fibrinolysis A. draws torn edges of damaged tissue closer together. B. forms thrombi. C. forms emboli. D. dissolves clots. E. activates fibrinogen.

D. dissolves clots.

Tissue factor is released after initiation in the A. common pathway. B. fibrinolytic pathway. C. intrinsic pathway. D. retraction pathway. E. extrinsic pathway.

E. extrinsic pathway.