A plant viroid

• Resources Structure
• Key Stage 4
• Biology
• II. The diversity of living organisms
• 18. Viruses

• Exam Specifications
• Key Stage 4
• AQA GCSE Science A (4461) Biology
• I. Biology 1a – Human Biology
• 4. What causes infectious diseases and how can our bodies defend themselves against them?
• Microorganisms that cause infectious disease are called pathogens.
• AQA GCSE Additional Science (4463) Biology
• III. Additional materials
• 1. Additional materials
• Additional materials
• AQA GCSE Biology (4411)
• II. Biology 1
• 4. What causes infectious diseases and how can our bodies defend themselves against them?
• to evaluate the consequences of mutations of bacteria and viruses in relation to epidemics and pandemics eg bird influenza.

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