Video Transcript
What is the main function of blood platelets? (A) Transporting blood cells and other substances around the body. (B) Helping the blood to clot to prevent bleeding. (C) Binding to oxygen to transport it to respiring cells. Or (D) targeting pathogens and fighting off infections.
This question asks about the function of platelets. So, to answer it, we need to figure out what platelets are and the role they play in the blood.
First, we need to understand the role of blood in the body. Blood is carried throughout our bodies in vessels, transporting vital nutrients and oxygen to our organs and tissues and removing waste material from them. This process is essential for maintaining life.
Blood consists of four main components, each playing a specific and unique role. The first component we’ll talk about is plasma. Plasma is the liquid medium that the other components travel in, transporting them to deliver oxygen and nutrients to and remove waste products from all of the organs of the body. We can therefore eliminate option (A), transporting blood cells and other substances around the body, because it describes the function of blood plasma. And we are looking for the role of the platelets.
Red blood cells are another component of the blood. They are the component that gives blood its characteristic red color. And the hemoglobin molecules within red blood cells bind to oxygen and allow it to be transported throughout the body. Option (C), binding to oxygen to transport it to respiring cells, describes the function of red blood cells. So it cannot be the correct answer.
Another component of blood is the white blood cells. White blood cells target pathogens and fight off infections. When blood vessels are exposed to the environment, for example, when you get a cut, potentially disease-causing pathogens like bacteria and viruses from the environment can enter into the bloodstream. White blood cells are most often able to identify them and prevent an infection. Option (D), targeting pathogens and fighting off infections, describes the function of white blood cells and can be excluded from our possible answers.
The final major component of blood that we have not yet explored is platelets. The main function of blood platelets is to help the blood form a clot. This can prevent excess bleeding when a blood vessel is damaged. Platelets react to damaged blood vessels by clumping together at the damage site, which initiates the formation of a thickened, solid mass of blood tissue called a blood clot. Clots plug up the break in the vessel and prevent more blood from escaping, thereby preventing further blood loss while the vessel heals.
This means that we have found the main function of platelets and therefore the correct answer to this question. The correct answer is option (B), helping the blood to clot to prevent bleeding.
