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Work through the notes, try the practice questions, then take the quiz. The report tells you exactly what to revise next. (2026)
Question
Describe three factors that can threaten food security. (6 marks)
Solution
Pick three distinct AQA-listed factors.
For each, explain how it reduces food availability.
Answer
(1) Rising population — more mouths to feed but limited land for farming. (2) Changing diets — richer countries eat more meat, which uses more land per calorie due to the 10% biomass rule. (3) New pests and pathogens — e.g. bird flu has killed millions of UK poultry, reducing food supply. (2 marks each.)
Question
Explain why increasing meat consumption in developed countries threatens global food security. (4 marks)
Solution
Meat is produced by feeding plants to animals — this is an extra trophic level.
Only ~10% of biomass transfers between levels — so 90% is 'lost' compared to eating plants directly.
This means more land, water and crops are needed per calorie of meat than per calorie of plant food.
Land/grain used to feed cattle isn't available to feed humans, reducing global food availability.
Answer
Meat production involves an extra trophic level — only ~10% of plant biomass becomes animal biomass (1). So producing the same calories from meat needs ~10× more land than producing them from plants (1). UK and other rich nations use cereals as animal feed (e.g. ~40% of UK cereals) (1). Less land for direct human food = global supply reduced and prices rise (1).
Question
Explain how restricting animal movement and controlling temperature increase the efficiency of food production. (4 marks)
Solution
Movement uses energy from respiration. Less movement = less respiration = less biomass lost.
Body heat (in endotherms) uses energy from respiration. Warm housing reduces this.
Both mean more of the feed biomass is converted to body mass (meat) rather than 'wasted'.
Answer
Restricting movement reduces the energy animals use in muscle activity / respiration (1), so less biomass is lost as heat (1). Controlling temperature (heated barns) reduces the energy needed to keep warm (1), so more of the feed's biomass becomes meat or eggs rather than being respired (1).
Question
Evaluate the use of intensive farming techniques in the UK to produce chicken. (6 marks)
Solution
Give advantages: efficiency, lower price, less land per kg.
Give disadvantages: animal welfare (no movement, stress), disease (avian flu), antibiotic resistance, environmental pollution.
Reach a reasoned conclusion — e.g. trade-off between affordability and welfare.
Answer
Advantages: chickens grow faster (35-42 days to slaughter), less feed needed per kg of meat, lower prices for consumers, less land used than free-range. Disadvantages: chickens have no space to move (welfare issue); disease spreads fast (e.g. 2022-23 avian flu killed millions); antibiotics used routinely → antibiotic resistance; slurry pollutes UK rivers. Conclusion: intensive farming feeds more people cheaply but at significant welfare and environmental cost — higher-welfare standards (free-range, RSPCA Assured) offer a middle ground.
Question
Describe three methods used to keep fishing sustainable. (6 marks)
Solution
Name three methods.
For each, explain HOW it keeps fish stocks healthy.
Answer
(1) Net mesh size control — large enough holes that small/young fish escape and grow up to breed (2). (2) Quotas — government sets legal limits on how much can be caught, so enough breeding fish are left in the sea (2). (3) No-fishing zones / Marine Protected Areas — areas closed to fishing, where fish breed and grow safely, then spill over to surrounding waters (2).
Question
Explain how using a larger mesh size in fishing nets helps maintain fish stocks. (3 marks)
Solution
Larger mesh has bigger holes.
Smaller / younger fish (juveniles) can pass through and escape.
These fish then grow up and breed, replenishing the population for the future.
Answer
Larger mesh has bigger holes (1), so small/juvenile fish can swim through and escape (1). These fish then grow up and breed, maintaining the population so the fishery is sustainable (1).
Question
Describe the conditions needed inside a fermenter for the production of mycoprotein from Fusarium fungus. (4 marks)
Solution
Sterile glucose syrup as food source for fungus.
Air (oxygen) pumped in for aerobic respiration.
Stirrer/agitator to keep contents mixed.
Cooling water jacket to remove heat from respiration; pH controlled around 6.
Answer
Sterile glucose syrup (and ammonia/minerals) added as food (1). Oxygen pumped in for aerobic respiration (1). Stirrer mixes contents so all fungi receive food and oxygen (1). Cooling jacket removes heat from respiration so temperature stays at ~28-30°C; pH controlled around 6 (1).
Question
Evaluate the use of genetically modified crops in addressing global food security. (6 marks)
Solution
Give benefits — yield, pest resistance, nutrition (golden rice).
Give concerns — cross-pollination, pest resistance, corporate control, ethical.
Reach a reasoned conclusion.
Answer
Benefits: GM crops can give higher yields (Bt maize resists insect pests, so fewer crops lost); reduce pesticide spraying; add nutrition (golden rice has beta-carotene to prevent vitamin A deficiency). Concerns: GM genes could cross-pollinate into wild plants; insect populations could develop resistance to Bt toxin; large corporations control patented seeds making farmers dependent; some have ethical/cultural objections. Conclusion: GM offers real benefits but each crop needs careful regulation and ecological assessment — blanket bans waste opportunities; blanket approval risks unintended harm.
Having access to enough safe, affordable and nutritious food to meet dietary needs for an active and healthy life.
The number of births per 1000 people per year. High birth rates contribute to population growth and increased food demand.
Producing food in ways that meet current needs without damaging the environment or ability to produce food in the future.
Farming techniques that maximise food production per unit of land or per animal, usually by restricting movement, controlling environment and feeding high-energy feeds.
Farming where animals have access to outdoor space and can express more natural behaviour — generally considered higher welfare but less efficient than intensive.
The kg of feed required to produce 1 kg of meat — a lower FCR means more efficient farming.
Fishing at a rate that allows fish populations to replace themselves, so the resource is preserved for future generations.
A legal limit on the amount of fish that can be caught — set per species, per area, per fishing fleet.
An area of sea legally protected from some or all fishing, allowing fish populations and ecosystems to recover.
Catching fish faster than the population can replace itself, leading to declining stocks.
The use of living organisms (or their parts/products) to make useful products such as food, medicine or biofuels.
A protein-rich food made from the fungus Fusarium grown in fermenters on glucose syrup — sold in the UK as Quorn.
A large sterile vessel used to grow microorganisms in controlled conditions for industrial production of food, drugs etc.
Changing an organism's DNA by adding, removing or altering genes — used to give crops useful traits like pest resistance.
Mistake
Just listing factors without explaining how they affect food security.
Why it happens
Rushing.
How to avoid it
For each factor, give ONE clear effect — e.g. 'pests destroy crops, reducing yield'.
Mistake
Thinking UK food security is independent of global events.
Why it happens
UK feels self-contained.
How to avoid it
UK imports ~40% of food — global shocks (Ukraine war, droughts abroad) directly hit UK shelves and prices.
Mistake
Thinking food insecurity only affects developing countries.
Why it happens
Most TV images come from Africa/Asia.
How to avoid it
~7% of UK households are food-insecure. Food bank use is rising even in wealthy nations.
Mistake
Saying 'restricting movement saves energy' without explaining where the energy comes from.
Why it happens
Forgetting the biology connection.
How to avoid it
Energy comes from respiration — moving muscles respire glucose; restricting movement reduces glucose used in respiration.
Mistake
Only listing advantages of intensive farming.
Why it happens
Focusing on the 'efficiency' angle.
How to avoid it
Always include welfare, disease, antibiotics, environment concerns — AQA evaluation needs balance.
Mistake
Saying temperature control means keeping animals cold.
Why it happens
Confusion with refrigeration.
How to avoid it
Heated barns keep animals WARM so they don't need to use energy to generate body heat. Especially important for chicks and young pigs.
Mistake
Saying 'quotas limit fishing' without saying what's limited.
Why it happens
Vague answer.
How to avoid it
Quotas limit the TOTAL CATCH (mass or number of fish) per year, per species, per fleet.
Mistake
Saying 'smaller mesh size lets juveniles escape'.
Why it happens
Confusing 'smaller' with 'better'.
How to avoid it
LARGER mesh has BIGGER HOLES — that's what lets small fish escape. Smaller mesh catches everything.
Mistake
Thinking MPAs ban fishing everywhere.
Why it happens
Names sound absolute.
How to avoid it
MPAs only protect SPECIFIC AREAS. Fishing continues outside those zones — the idea is to give fish safe places to breed.
Mistake
Saying mycoprotein is made from yeast.
Why it happens
Yeast is the more familiar fungus.
How to avoid it
Mycoprotein is from Fusarium. Yeast (Saccharomyces) makes bread and beer — a different fungus.
Mistake
Saying fermenters work anaerobically.
Why it happens
Word 'ferment' suggests anaerobic.
How to avoid it
Mycoprotein production is AEROBIC — oxygen is pumped in. Beer/wine fermentation is anaerobic but mycoprotein production is not.
Mistake
Confusing GM with selective breeding.
Why it happens
Both 'create new varieties'.
How to avoid it
Selective breeding = choosing parent organisms to breed (slow, natural). GM = directly inserting DNA in a lab (fast, can use genes from other species).