What is the function of platelets in the blood?

• A. To transport nutrients to body cells
• B. To produce hormones for metabolic functions
• C. To aid in blood clotting and prevent bleeding
• D. To remove carbon dioxide from the body

Answer: (C)

Platelets, or thrombocytes, play a crucial role in hemostasis, which is the process of blood clotting. When a blood vessel is injured, platelets quickly aggregate at the site of the wound, adhering to the exposed tissue and each other, forming a temporary "platelet plug." This action is essential for stopping bleeding and facilitating the healing process. Additionally, platelets release chemical signals that not only promote further aggregation and recruitment of additional platelets but also activate the coagulation cascade, resulting in the formation of a stable blood clot. This function is vital for preventing blood loss and allowing for recovery from injuries.

The other options pertain to functions that are carried out by different types of blood cells or organs in the body. For instance, red blood cells are primarily responsible for transporting oxygen and, to some extent, carbon dioxide. Hormone production is typically the role of endocrine glands and certain specialized cells, rather than blood components. Lastly, the removal of carbon dioxide is mainly facilitated by red blood cells and the respiratory system, not platelets.