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Defending against disease

5 lessons in Infection and response.

30 exam questions · 60 marks

3.8 Non-specific defences How the body stops pathogens getting in: the skin, hairs and mucus in the nose, mucus and cilia in the trachea and bronchi, hydrochloric acid in the stomach, lysozymes in tears and blood clotting. AQA Edexcel OCR 3.9 White blood cells and the immune response How white blood cells defend the body: phagocytosis, antibodies that fit the antigens on a pathogen, antitoxins, memory lymphocytes, and why the secondary immune response is faster and larger than the primary response. AQA Edexcel OCR 3.10 Vaccination How a vaccine of dead or inactive pathogen makes lymphocytes produce antibodies and memory cells, why this gives immunity, how herd immunity protects people who are not vaccinated, and the advantages and disadvantages of vaccination. AQA Edexcel OCR 3.11 Antibiotics and painkillers How antibiotics such as penicillin kill bacteria but not viruses, why painkillers only treat symptoms, how antibiotic resistance develops and how to slow it, and how antivirals and antiseptics are used. AQA Edexcel OCR 3.12 Discovering and developing drugs Where drugs come from (digitalis from foxgloves, aspirin from willow, penicillin from mould), and how new drugs are tested for toxicity, efficacy and dose in preclinical and clinical trials, including double blind trials and placebos. AQA Edexcel OCR