True or False: Heparin inhibits coagulation at the end of the cascade after most proteins have become active.

Heparin is an anticoagulant that primarily inhibits coagulation factors in the early stages of the coagulation cascade. It works mainly by activating antithrombin III, which inactivates thrombin (factor IIa) and factor Xa, among others. By targeting these key factors at the beginning of the cascade, heparin effectively prevents the conversion of fibrinogen to fibrin and stops the formation of clots before they can develop further.

Since heparin acts on factors that are crucial for initiating the coagulation process, it is incorrect to state that it inhibits coagulation at the end of the cascade, where most proteins have already become activated. The correct understanding is that heparin plays a protective role early on within the coagulation pathway. Thus, the statement claiming that heparin inhibits coagulation at the end of the cascade would be considered false.