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no
Antibiotic targets are generally bacterial structures or processes.
Class 9 · English Medium · Pearson Edexcel · Biology
Ecology, health and disease
Explain ecological relationships, transmission and prevention as biological mechanisms.
Shared cross-level core and stretch unit. Start with the core questions, then use the stretch example for deeper work. The same unit is available in related class and board pathways; it is not a full grade-specific or examination-specification course. A teacher should select the appropriate depth and further topics.
Learn the idea
A pathogen can cause disease; transmission depends on the organism and route. Immunity involves recognition and responses to specific targets. Antibiotics act on susceptible bacteria, not viruses as a class. Population-level prevention claims need context, and this lesson does not diagnose or prescribe treatment.
Worked example
A fictional waterborne pathogen can spread through contaminated water. Treating water and preventing contamination interrupt the route. An ecosystem disturbance can also change contact patterns between hosts and vectors.
- Identify the organism and transmission route.
- Explain how a measure interrupts that route.
- Separate a general mechanism from an individual medical decision.
Stretch example
Vaccination can establish immune memory without the disease episode it aims to prevent. Effectiveness varies by pathogen, outcome, time and population; a blanket guarantee would be misleading.
Your written practice
Show your working on paper and enter your answer here. If it does not match, compare the model and try again.
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vector
A vector transmits a pathogen between hosts.
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mutualism
Both partners obtain a benefit in this defined interaction.
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It can change contact between hosts, vectors and pathogens.
Explain a route; do not assume every habitat change has the same effect.
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Infection is establishment of a pathogen; disease involves harmful disturbance or symptoms and need not occur in every infection.
Avoid equating any exposure with illness.
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B
B lymphocytes can form plasma cells.
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They are different outcomes and a measure can affect them by different amounts.
Name the outcome being measured.
Mechanism diagram
Draw a fictional transmission chain and two points where it could be interrupted.
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- Label the route.
- Explain each interruption.
- Avoid personal diagnosis or treatment instructions.
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