This exam focus covers Exam Focus within Pathogens and Disease Transmission for GCSE Biology. Types of pathogens, how diseases spread, transmission methods, and prevention strategies It is section 16 of 18 in this topic. Treat this as a marking guide for what examiners are looking for, not just a fact list.
Topic position
Section 16 of 18
Practice
18 questions
Recall
20 flashcards
Exam Focus
Very Frequently ExaminedPathogens and disease transmission is examined in almost every AQA Paper 2 series. Questions typically combine knowledge of pathogen types with transmission routes and prevention strategies.
- Pathogen identification (2-3 marks): Given a disease name, state the type of pathogen and explain one feature that distinguishes it from other pathogen types. Know at least two examples per type.
- Transmission description (3-4 marks): The most common question format. Give the transmission route, the mechanism (how the pathogen actually moves), and the prevention method. Do not just name the route — explain how it works.
- Why antibiotics fail on viruses (2 marks): Antibiotics target bacterial cell structures (cell walls, ribosomes). Viruses have neither. This exact point is worth memorising word-for-word.
- Required practical (3-4 marks): Disc diffusion method — know the independent variable (type of substance), dependent variable (zone of inhibition diameter), control variables, and why 25°C is used instead of 37°C.
- Data interpretation: Graphs showing disease incidence over time or bar charts comparing zone sizes are common. Always read axis labels carefully and quote data in your answer.
Common mark losses: Saying antibiotics "destroy virus cells" (viruses are not cells). Confusing vector (the mosquito) with pathogen (Plasmodium). Not explaining the mechanism — just naming the transmission route without saying how the pathogen moves.