The body’s defence mechanisms

• The body is equipped to deal with and defend itself against diseases and infections
• These defends, while inadequate, are effective and essential

Some of the body’s defenses. Image credit schoolbag.info

• Skin-is a physical barrier against all bacteria and other pathogens
• Wax and hairs-found in the ears prevent invasion by microorganisms
• Mucus and hairs-found in the nose trap invading bacteria and spores
• Stomach acids-they kill bacteria in the food
• White blood cells-some of them engulf and digest bacteria while others produce antibodies to destroy bacteria/neutralise toxins/poisons produced by bacteria
• Tears-have a mild antiseptic to kill bacteria in the eyes
• Blood clotting-is caused by platelets in the blood at damaged parts of the skin. This involves blood proteins in the plasma forming a network of fibres and eventually clotting. Clotting also helps prevent loss of blood.
• Saliva-it has a cleansing action

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