Pearson Edexcel International GCSE Biology · specification 4BI1 · Paper 2 | Whole paper: All content including bold B statements · Free · no account needed
4(d) Human influences on the environment (4BI1 specification)
Pollution, greenhouse gases, eutrophication and deforestation — each with a specific mechanism to learn.
Learn it on Incandio
The 4 Incandio pages that teach this — each explained in full, then proved in marked questions, taught back to an AI pupil and defended in a debate. Completely free.
- The Carbon and Nitrogen Cycles — The same atoms, used again and again — and the four bacteria that do the work nothing else can.
- Air Pollution and the Greenhouse Gases — Two entirely different problems that both begin with burning — one that poisons what it touches, and one that changes the energy balance of the planet.
- Global Warming and Deforestation — What a warmer planet does to living things — and why removing a forest changes the soil, the rainfall and the atmosphere all at once.
- Water Pollution and Eutrophication — Two things that should be harmless — treated sewage and plant fertiliser — and the same chain of events by which both empty a river of fish.
The teaching route this belongs to: Topic 4 · Ecology and the environment (Biology) — the lessons in order, with every gate.
Specification coverage
Topic 4 Ecology and the environment (d) Human influences on the environment — statements 4.11–4.17B (includes bold B statements assessed on Paper 2 only)
Assessment objectives: AO1, AO2. Suggested learning time: 70 minutes.
Required knowledge
- The greenhouse effect, the gases responsible and the biological consequences of climate change
- The causes and consequences of acid rain
- Eutrophication: its causes and the sequence of events that leads to the death of aquatic organisms
- The effects of deforestation, including on species diversity, soil erosion and the carbon cycle
- Bold B statements: the biological consequences of pollution in greater depth
Required skills
- Set out eutrophication as an ordered sequence
- Evaluate data on pollutant concentration and its effects
How it is examined
- Multiple-choice and short-answer recall
- Application of the content to an unfamiliar context
- Extended open-response, marked on the quality of a connected explanation
Common mistakes
- Saying eutrophication happens 'because of fertiliser' and stopping. The sequence — nutrients, algal bloom, light blocked, plants die, decomposers multiply, oxygen depleted, fish die — is what carries the marks.
- Confusing the greenhouse effect with the depletion of the ozone layer. They are different problems with different causes.
This page maps the specification. The pages above teach it, and the Biology lessons hold the whole course — completely free.