Abnormal red blood cell counts have what consequences on health?

A. arteriole: arterioles are small, muscular arteries with thicker walls and no valves; lymphatics are thin-walled and valved.
B. artery: arteries have thick, muscular, elastic walls to withstand high pressure; lymphatic vessels are thin-walled and low-pressure.
C. capillary: capillaries are tiny single-cell-thick vessels for exchange; lymphatics are larger and have valves.
D. vein: lymphatic vessels have thin walls and valves and operate under low pressure, making them most similar in structure/function to veins.

A. Converts fibrinogen to fibrin: that reaction is carried out by thrombin, not plasmin.
B. Breaks down fibrin, dissolving the clot: plasmin is the primary enzyme of fibrinolysis, cleaving fibrin to dissolve formed clots.
C. Triggers the extrinsic clotting mechanism, leading to clot formation: the extrinsic pathway is initiated by tissue factor (factor III) interacting with factor VII, not plasmin.
D. Inactivates thrombin, slowing clot formation: plasmin’s main role is fibrin breakdown; thrombin is primarily regulated by antithrombin, thrombomodulin–protein C systems. (Plasmin can degrade some clotting proteins but it is not described as the main inactivator of thrombin.)