Ecology | AQA GCSE Biology, Higher tier (8461)
Ecology
- 228 questions
- 18 subtopics
- Paper 2
- Paper 2
Ecology is examined in Biology Paper 2.
It covers levels of organisation in an ecosystem, and what organisms need, competition, interdependence and stable communities, abiotic factors, biotic factors, adaptations, producers, food chains and sampling with quadrats and transects, predators, prey and measuring population size, how materials are cycled, decomposition, waste management and biodiversity, land use, deforestation and global warming, maintaining biodiversity, trophic levels and pyramids of biomass, transfer of biomass, factors affecting food security, farming techniques and sustainable fisheries, role of biotechnology and impact of environmental change.
Sample questions from Ecology
Answer each one closed book first, then open the answer.
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Levels of organisation in an ecosystem, and what organisms need
What is an ecosystem?
Show the answer
The interaction of a community of living organisms with the non-living parts of their environment. -
Abiotic factors
Why is the direction of the wind, as well as its strength, an abiotic factor?
Show the answer
A steady wind from one direction dries and damages one side of a plant, so growth is lopsided and exposed sides support fewer plants. -
Adaptations
What is a functional adaptation?
Show the answer
A feature of the way an organism's body works, such as producing very concentrated urine or slowing its metabolism. -
Predators, prey and measuring population size
What is prey?
Show the answer
An animal that is killed and eaten by a predator. -
Decomposition
Name three conditions a gardener provides in a compost heap to speed up decay.
Show the answer
Warmth, moisture and a good supply of oxygen from turning the heap. -
Land use, deforestation and global warming
Describe how the destruction of peat adds carbon dioxide to the atmosphere.
Show the answer
Once removed the peat decays or is burned, and both of these release carbon dioxide. -
Trophic levels and pyramids of biomass
What is a secondary consumer, and which trophic level does it occupy?
Show the answer
A carnivore that eats herbivores, at trophic level 3. -
Factors affecting food security
How can a new pathogen threaten food security?
Show the answer
It causes disease in crops or farm animals, so less food is produced.
The 18 subtopics
One subtopic is one session. Work down the list.
| Subtopic | What it covers | Questions |
|---|---|---|
| Levels of organisation in an ecosystem, and what organisms need | Population, community, habitat and ecosystem, biotic and abiotic parts, what plants and animals must obtain to survive, and competition and adaptation in rock pools, deserts and streams. | 12 |
| Competition, interdependence and stable communities | What plants and animals compete for, with seedlings under trees and fighting deer, interdependence and what species depend on each other for, stable communities, the effects of losing bees or a single species, and reading producers and competition from tables. | 12 |
| Abiotic factors | The seven abiotic factors, dissolved oxygen in water, soil pH and minerals, wind direction, and how moisture, warming, acid rain, shelter and light change a community. | 12 |
| Biotic factors | Food availability, new predators, new pathogens and competition as biotic factors, with red and grey squirrels, poor acorn crops, island prey, lost plant species and diseased ash trees, and interpreting population data on introduced species and disease. | 12 |
| Adaptations | Structural, behavioural and functional adaptations, extremophiles such as deep sea vent bacteria and their enzymes, and examples including whale blubber, camel urine, Arctic fox ears and cactus spines and stems. | 12 |
| Producers, food chains and sampling with quadrats and transects | Producers and biomass, why a producer starts every food chain and what the arrows mean, quadrats and transects, distribution against abundance, and the mean, median and mode of counts. | 13 |
| Predators, prey and measuring population size | Primary, secondary and tertiary consumers, predators and prey and their cycling numbers, estimating a field's dandelions with random quadrats, and using a transect along a footpath. | 13 |
| How materials are cycled | Why materials must be recycled, the carbon cycle through photosynthesis, respiration, combustion and decomposers, the water cycle through evaporation, condensation and precipitation, and the role of microorganisms in returning carbon dioxide and mineral ions. | 13 |
| Decomposition | How temperature, water and oxygen set the rate of decay, compost heaps and biogas generators, and the milk decay investigation with its pH and rate calculations. | 13 |
| Waste management and biodiversity | Why a growing population and rising living standards produce more waste, sources of water, air and land pollution, how fertiliser, acid rain and toxic chemicals damage ecosystems, and what biodiversity is, why it makes ecosystems stable and how human activity has reduced it. | 16 |
| Land use, deforestation and global warming | Land lost to building, quarrying, farming and waste, peat bog destruction and the carbon dioxide it releases, tropical deforestation for cattle, rice and biofuels, carbon dioxide and methane in global warming, and its effects on species distribution and sea levels. | 13 |
| Maintaining biodiversity | Breeding programmes, habitat protection, field margins and hedgerows, recycling and cutting deforestation and carbon dioxide emissions, negative and positive human interactions with ecosystems, and the conflicts that conservation programmes can cause. | 12 |
| Trophic levels and pyramids of biomass | Trophic levels from producers through primary, secondary and tertiary consumers to apex predators, animals feeding at more than one level, how decomposers digest dead matter, and drawing pyramids of biomass. | 14 |
| Transfer of biomass | The shape of a pyramid of biomass, the 1% of light used in photosynthesis, the 10% passed between trophic levels, where biomass is lost, and efficiency calculations. | 14 |
| Factors affecting food security | What food security is, how birth rate, changing diets, pests, pathogens, drought, farming costs and conflict threaten it, sustainable food production, and why eating crops directly feeds more people than feeding them to animals. | 13 |
| Farming techniques and sustainable fisheries | Improving the efficiency of meat production by limiting movement and heat loss, housed and free-range animals, fish cages and high protein food, declining fish stocks, and conserving them with net mesh sizes and fishing quotas. | 13 |
| Role of biotechnology | Culturing microorganisms for food, making mycoprotein from Fusarium grown on glucose syrup, producing human insulin from genetically modified bacteria, genetically modified crops including golden rice, and the arguments against them. | 13 |
| Impact of environmental change | Temperature, water and atmospheric gases as changes that shift where a species lives, their seasonal, geographic and human causes, and evaluating a warmed river and city lichens. | 8 |
How the guide is worked
Answering a question from memory stores it far better than reading the answer again. The guide runs that as a fixed procedure on one subtopic at a time, about twenty minutes a session.
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Step 1 · Closed book
Cover the answers. Work through one subtopic and write down what you can. Leave blanks where you have nothing.
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Step 2 · Open book
Go back to the top. Read each printed answer and write it out in full, including the ones you had right.
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Step 3 · Closed book again
Same questions, same order, from memory. The gap between pass one and pass three is the session result.
Read the full method, the return schedule and the research behind it.
Nearby topics
AQA GCSE Biology, Higher tier Active Recall Guide
Every topic, not just this one. 1,475 questions with their answers.