What does the ecology and the environment module cover?

This module covers Unit 1 sections 1.7 to 1.8: ecological relationships and the key terms population, community and ecosystem, energy flow through food chains and pyramids, the carbon and nitrogen cycles, sampling with quadrats and transects and the meaning of biodiversity, and human impact through pollution, habitat destruction and conservation.

Which exam assesses this module?

These topics are part of Unit 1 Cells, Living Processes and Biodiversity, a written paper worth 35 percent of the GCSE. Foundation tier lasts 1 hour 15 minutes and Higher tier lasts 1 hour 30 minutes, and a calculator is allowed for the energy-transfer and population calculations.

What calculations come up in this module?

The two main calculations are energy transfer efficiency, where you divide the energy passed on by the energy available and multiply by 100, and estimating a population from quadrat data by finding the mean per quadrat and scaling up by area. You also interpret pyramids of biomass and predator-prey graphs.

What practicals and fieldwork are linked to this module?

Fieldwork includes using quadrats placed randomly to estimate abundance and percentage cover, and using a transect with quadrats at regular intervals to study how distribution changes along an environmental gradient. You may also use indicator species to assess water or air pollution.

How should I revise this module?

Learn the key terms precisely, get the direction of food-chain arrows right, and learn why energy is lost at each trophic level. Memorise the carbon cycle processes and the four types of bacteria in the nitrogen cycle. Practise the energy-transfer and population calculations, learn the eutrophication sequence, and rehearse CCEA past-paper questions.

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CCEA GCSE Biology: Ecology and the environment overview

An overview of the ecology and the environment module of CCEA GCSE Biology (Unit 1 sections 1.7 to 1.8), mapping ecological relationships, energy flow and food chains, the carbon and nitrogen cycles, sampling and biodiversity, and human impact on the environment, and how they are examined.

Generated by Claude Opus 4.87 min readCCEA 6568 Unit 1.7 to 1.8Updated 2026-06-14

Reviewed by: AI editorial process; not yet individually human-reviewed

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What this module covers
How it is examined
How to study it

This module is about organisms and their environment. It covers Unit 1 sections 1.7 to 1.8 and is examined on the Unit 1 written paper. This page maps the topics and links to a focused answer page for each.

What this module covers

Ecological relationships: The terms population, community, habitat and ecosystem, producers, consumers and decomposers, food chains and webs, and interdependence including predator and prey relationships. Start with Ecological relationships.
Energy flow and food chains: How energy from the Sun flows through food chains, why energy is lost at each level, pyramids of numbers and biomass, and energy-transfer calculations. See Energy flow and food chains.
Nutrient cycles: The carbon cycle and the nitrogen cycle, including the roles of decomposers and the nitrogen-fixing, nitrifying and denitrifying bacteria. See Nutrient cycles.
Sampling and biodiversity: Using quadrats and transects, the meaning of biodiversity, and population estimates from data. See Sampling and biodiversity.
Human impact on the environment: Water and air pollution, indicator species, habitat destruction and deforestation, and conservation. See Human impact on the environment.

How it is examined

These topics appear on Unit 1, worth 35% of the GCSE. Expect structured questions on ecological terms, food webs and energy loss, the carbon and nitrogen cycles, quadrat and transect methods, and a longer answer such as eutrophication. Calculations on energy transfer and population estimates are common.

How to study it

Learn the key terms and the direction of food-chain arrows, then the reasons energy is lost at each trophic level. Memorise the carbon cycle and the four nitrogen-cycle bacteria, and practise the energy-transfer and population-estimate calculations until they are automatic. Learn the eutrophication sequence, then work through CCEA past papers and finish with the module quiz.

Sources & how we know this

CCEA GCSE Biology specification — CCEA (2017)