What is the function of platelets?

What is the function of platelets?

• A. Prevent blood loss and help with clotting.
• B. Protect the body against pathogens.
• C. Transport oxygen and carbon dioxide.
• D. Regulate digestion by maintaining normal pH.

Answer: (A)

Platelets are the cells that initiate stopping bleeding. When a vessel is damaged, they adhere to the exposed tissue, aggregate to form a temporary plug, and release signaling molecules that kick off the coagulation cascade, creating a fibrin mesh that strengthens and stabilizes the clot. This combined action prevents blood loss after injury. The other options describe roles of different blood components: immunity involves white blood cells, oxygen transport comes from red blood cells, and digestion-related pH regulation involves other systems, not platelets.

Platelets are the cells that initiate stopping bleeding. When a vessel is damaged, they adhere to the exposed tissue, aggregate to form a temporary plug, and release signaling molecules that kick off the coagulation cascade, creating a fibrin mesh that strengthens and stabilizes the clot. This combined action prevents blood loss after injury. The other options describe roles of different blood components: immunity involves white blood cells, oxygen transport comes from red blood cells, and digestion-related pH regulation involves other systems, not platelets.