Explain the role of platelets in blood. [3 MARKS]

Each point: 1 Mark

1. If blood vessel develops a leak like an injury, the loss of blood from the system has to be minimized.
2. In addition, leakage would lead to a loss of pressure which would reduce the efficiency of the pumping system.
3. To avoid this, the blood has platelets which circulate around the body in blood vessels and plug these leaks by helping to form a blood clot at these points of injury.