Which of the following is a primary function of platelets?

• A. Initiating blood clotting
• B. Transporting oxygen
• C. Regulating blood pH
• D. Producing antibodies

Answer: (A)

Verified step by step guidance

1. Understand the role of platelets in the circulatory system. Platelets, also known as thrombocytes, are small cell fragments in the blood that play a crucial role in hemostasis (the process of stopping bleeding). Their primary function is related to blood clotting.
2. Review the process of blood clotting. When a blood vessel is injured, platelets adhere to the damaged area and release chemicals that activate other platelets. This forms a temporary plug to prevent further blood loss.
3. Compare the listed options with the known functions of platelets. Platelets do not transport oxygen (this is the role of red blood cells), regulate blood pH (this is managed by buffers in the blood), or produce antibodies (this is the role of B cells in the immune system).
4. Focus on the correct function: initiating blood clotting. Platelets are essential for starting the clotting cascade, which involves a series of chemical reactions leading to the formation of a stable blood clot.
5. Conclude that the correct answer is 'Initiating blood clotting,' as this aligns with the primary function of platelets in the circulatory system.