Year 8 science lesson on how the immune system works. Resources from Education Using Powerpoint, Boardworks & Framework.

3. Microbes: our defence against them Our bodies have many defence mechanisms against invading microbes: If our skin is cut platelets seal the wound by clotting The breathing organs produce mucus to cover the lining of these organs and trap the microbes The skin acts as a barrier Stomach produces stomach acid Tears contain an enzyme that kills bacteria

5. Phagocyte engulfs microbe – animation Animation

6. Lymphocytes and antibodies – animation Animation

7. Producing antibodies Step 1: The white blood cell “sees” the antigen (microbe) Step 2: The cell produces antibodies to “fit” the antigen Step 3: The antibodies fit onto the antigens and cause them to “clump” Step 4: The antigens are “eaten” by the white blood cells You’re going down

9. A Microbe multiplies and creates illness. B Microbe enters body. C Body responds slowly. D Body responds quickly. Microbe is killed before it has a chance to multiply and cause illness. E Microbe enters body. F Body produces enough antibodies and white blood cells to kill invading microbe. As microbe dies the symptoms disappear. E Microbe enters body. C Body responds slowly. A Microbe multiplies and creates illness. F Body produces enough antibodies and white blood cells to kill invading microbe. As microbe dies the symptoms disappear. B Microbe enters body. D Body responds quickly. Microbe is killed before it has a chance to multiply and cause illness. 8C Vaccination Put these events into the right order.

10. Multiple-choice quiz