Anatomy and Physiology II Practice Test

Which of the following cell types is involved in blood clotting?

1. Erythrocyte

2. Basophil

3. Thrombocyte

4. Eosinophil

The correct answer is: Thrombocyte

Thrombocytes, commonly known as platelets, play a pivotal role in blood clotting, also referred to as hemostasis. These small, disc-shaped cell fragments are produced in the bone marrow and are essential for vascular repair. When a blood vessel is injured, platelets adhere to the site of damage and become activated. This activation leads to a series of reactions that enhance their ability to clump together, forming a temporary "platelet plug" to halt bleeding. Additionally, platelets release various chemical signals that recruit even more platelets to the site of injury, further stabilizing the clot. They also help facilitate the conversion of fibrinogen to fibrin, which strands together to provide a solid matrix for the clot. Thus, thrombocytes are integral to the clotting cascade, ensuring that bleeding is effectively controlled and healing can commence. In contrast, erythrocytes (red blood cells) primarily function in oxygen transport, basophils are involved in inflammatory responses and release histamine, and eosinophils are key in combating parasitic infections and mediating allergic reactions. None of these cell types play a direct role in the clotting process like thrombocytes do.