NURS 6501: Final Exam: Please contact Assignment Samurai for help with NURS 6501: Final Exam or any other assignment. Email: assignmentsamurai@gmail.com   In the platelet response to vascular injury, which encompasses adhesion, aggregation, and release, which is the first process in the platelet adhesion reaction? Group of answer choices

• GPIIbIIIa crosslinks with fibrinogen.
• Fibrinogen is converted into fibrin by thrombin.
• Cross-linking of GPib on the platelet surface to exposed collagen via von Willebrand factor
• The platelets are activated and release their granules into the microenvironment.

  The correct answer is: Cross-linking of GPib on the platelet surface to exposed collagen via von Willebrand factor   Explanation: In the platelet adhesion process after vascular injury, the first step is the interaction of platelets with the exposed subendothelial collagen at the site of injury. This process is mediated by the von Willebrand factor (vWF), which acts as a bridge between the platelet receptor GP Ib and the collagen. This interaction is crucial for the initial adhesion of platelets to the damaged vessel wall.   Here’s why the other options are incorrect: GPIIbIIIa crosslinks with fibrinogen: This occurs later in the process, during platelet aggregation, when platelets bind to fibrinogen to form a platelet plug.   Fibrinogen is converted into fibrin by thrombin: This is part of the coagulation cascade and occurs after platelet aggregation, contributing to the stabilization of the clot.   The platelets are activated and release their granules into the microenvironment: This occurs after the initial adhesion, during platelet activation, where platelet granules are released, but it is not the first step.   Thus, the first step in platelet adhesion is the cross-linking of GP Ib on the platelet surface to exposed collagen via von Willebrand factor.