Blood Clotting (Cambridge International IGCSE Biology)

Spec point — 9.4.4 · State the roles of blood clotting as preventing blood loss and the entry of pathogens

Blood clotting

• Platelets are fragments of cells which are involved in blood clotting and forming scabs where the skin has been cut or punctured
• Blood clotting prevents continued / significant blood loss from wounds
• Scab formation seals the wound with an insoluble patch that prevents entry of microorganisms that could cause infection
• It remains in place until new skin has grown underneath it, sealing the skin again