An individual with a genetic defect has normal platelet counts but prolonged bleeding times after minor injuries. Which mechanism explains why factor VIII's absence affects clotting?

💡 Explanation

Factor VIII is essential for the intrinsic pathway of the coagulation cascade; because its absence prevents activation of factor X, initiation of the clotting cascade is blocked. Therefore, the bleeding time is prolonged, rather than caused by impaired fibrinogen activation or vitamin K function.

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