Show model answer and explanation
no
Antibiotic targets are generally bacterial structures or processes.
A Level · 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.
Show model answer and explanation
vector
A vector transmits a pathogen between hosts.
Show model answer and explanation
mutualism
Both partners obtain a benefit in this defined interaction.
Write in your own words. A guardian or teacher should review this response.
Show model answer and explanation
It can change contact between hosts, vectors and pathogens.
Explain a route; do not assume every habitat change has the same effect.
Write in your own words. A guardian or teacher should review this response.
Show model answer and explanation
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.
Show model answer and explanation
B
B lymphocytes can form plasma cells.
Write in your own words. A guardian or teacher should review this response.
Show model answer and explanation
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.
Review with a guardian or teacher
- Label the route.
- Explain each interruption.
- Avoid personal diagnosis or treatment instructions.
Keep your work on paper or in a local file. This page does not upload it or automatically grade the project.
Teacher-led lessons, schedules and prices for this outline are upcoming. You can use any starter practice above now without booking.
Your next step
Solo practice works without an account. Sign in to save a practice record to your learner profile.
Keep practising
Exact lesson links and related activities are labelled separately. Return-to-course links retain your selected learning path.