Progressive Care Nursing Certification (PCCN) Practice Exam

What effect does thromboxane A2 have on platelets?

1. It activates them for clot formation

2. It inhibits their aggregation

3. It decreases their production

4. It causes them to undergo apoptosis

The correct answer is: It activates them for clot formation

Thromboxane A2 (TXA2) is a potent signaling molecule primarily produced by platelets. Its main role is to facilitate platelet activation and aggregation, which are essential processes in the formation of blood clots. When platelets are activated, they release thromboxane A2, which subsequently acts on other platelets to enhance their activation and promote aggregation. This creates a positive feedback loop that is crucial for quickly forming a platelet plug at the site of vascular injury, thereby playing a vital role in hemostasis. The other choices refer to processes that either do not align with the function of thromboxane A2 or describe effects that are not applicable in the context of its role in platelet physiology. In summary, thromboxane A2 primarily activates platelets for clot formation, making the correct answer consistent with its established biological function.