Treating, curing and preventing disease Edexcel GCSE Biology – by BBC bitesize Treating, curing and preventing disease The immune system defends humans from pathogens. Physical and chemical barriers prevent infection. White blood cells attack pathogens. Immunizations usually involve injecting inactive pathogens. Topic Content 0% Complete 0/12 Steps Defence against infection The immune system defends against disease Immunisations Herd immunity Advantages and disadvantages of immunisation Maths skills – Extracting and interpreting information Antibiotics Antibiotic resistance Bacterial growth in cultures Maths – Bacterial calculations Core practical Maths skills Previous Topic Back to Subject Next Topic