Some of the biological challenges of increasing food yields using fewer resources
This topic examines the complex challenges of balancing the growing global demand for food and economic development with the necessity of environmental conservation. It explores how scientific monitoring and biotechnological advancements, such as genetic modification, can be utilized to improve food security while minimizing the impact on wildlife and natural resources.
Quick Revision Summary (Key Takeaway)
This topic covers the biological challenges of increasing food yields sustainably, focusing on reducing inputs like water, fertilisers, and energy while maintaining or boosting crop and livestock productivity. Key strategies include genetic modification, precision agriculture, and integrated pest management, which address resource efficiency and environmental impact.
Topic Overview
This topic explores the biological challenges of meeting the growing global demand for food while using fewer resources such as water, fertilisers, and energy. It is a key part of WJEC GCSE Biology, linking ecology, genetics, and human impact on the environment. Students learn about the pressures on food production, including climate change, population growth, and soil degradation, and the need for sustainable solutions.
The core of this topic involves evaluating methods like genetic modification, selective breeding, and agricultural technologies. These methods aim to increase yield per unit of input, reduce waste, and minimise environmental damage. Understanding these challenges is crucial for future careers in agriculture, environmental science, and biotechnology, and for making informed decisions as global citizens.
This topic builds on earlier knowledge of photosynthesis, plant nutrition, and ecosystems. It also connects to topics on variation, inheritance, and biotechnology. By the end, students should be able to critically assess the pros and cons of different strategies, using data and case studies to support their arguments.
Key Concepts
Core ideas you must understand for this topic
- →Yield is the amount of food produced per unit area of land, and increasing it sustainably means using fewer inputs like water, fertiliser, and energy.
- →Genetic modification (GM) can create crops with traits such as pest resistance, drought tolerance, or improved nutrient use efficiency, reducing resource inputs.
- →Precision agriculture uses technology like GPS and sensors to apply water, fertiliser, and pesticides only where needed, minimising waste.
- →Integrated pest management (IPM) combines biological, cultural, and chemical methods to control pests while reducing chemical use.
- →Sustainable food production must balance economic viability, environmental impact, and social responsibility.
What You Need to Demonstrate
Key skills and knowledge for this topic
- Balancing human food requirements and economic development with wildlife needs
- Role of scientific information and monitoring in environmental management
- Biological factors affecting food security (population growth, diet changes, pests, pathogens, environmental change, sustainability, agricultural inputs)
- Biotechnological and agricultural solutions to food security
- Use of genetic modification to increase food yields
Marking Points
Key points examiners look for in your answers
- Balancing human food requirements and economic development with wildlife needs
- Role of scientific information and monitoring in environmental management
- Biological factors affecting food security (population growth, diet changes, pests, pathogens, environmental change, sustainability, agricultural inputs)
- Biotechnological and agricultural solutions to food security
- Use of genetic modification to increase food yields
Examiner Tips
Expert advice for maximising your marks
- 💡Be prepared to evaluate the impact of agricultural practices on biodiversity
- 💡Use specific examples of biological factors (e.g., pests, pathogens) when discussing food security
- 💡Ensure you can explain how scientific data informs management decisions by organizations like the Environment Agency
- 💡Use specific examples in your answers, such as Bt corn or drought-tolerant wheat, to show application of knowledge.
- 💡Always link methods to the challenge of using fewer resources – state which resource is saved and how.
- 💡In evaluation questions, give balanced arguments and a justified conclusion.
Common Mistakes
Pitfalls to avoid in your exam answers
- Failing to link food security factors to the specific biological challenges mentioned
- Confusing the role of monitoring agencies with direct environmental intervention
- Overgeneralizing the benefits of genetic modification without acknowledging the balance of risks
- Misconception: 'Organic farming always has higher yields than conventional farming.' Correction: Organic farming often has lower yields, but it uses fewer synthetic inputs, so the challenge is to increase its efficiency.
- Misconception: 'GM crops are always bad for the environment.' Correction: GM crops can reduce pesticide use and increase yields, but they may have risks like gene flow; the impact depends on how they are used.
- Misconception: 'Increasing fertiliser always increases yield.' Correction: Beyond a certain point, extra fertiliser can damage plants and cause pollution, so there is an optimum level.
Revision Plan
How to revise this topic in 1–2 weeks
- 1Week 1: Review photosynthesis and plant nutrition. Then learn about the challenges of food production (population growth, climate change).
- 2Week 2: Study each method in detail: GM, selective breeding, precision agriculture, and IPM. Make notes on pros and cons.
- 3Week 3: Practise data analysis questions (e.g., yield graphs) and 6-mark evaluation questions. Use past papers.
- 4Week 4: Revise key terms and misconceptions. Create flashcards for definitions and examples. Do a timed mock question.
Exam Question Types
How this topic typically appears in the exam
- 📋Data analysis questions: interpret graphs or tables showing yield vs. fertiliser use or water use. Look for trends and explain them.
- 📋Evaluation questions: 'Evaluate the use of GM crops to increase food yield.' Give points for and against, then a conclusion.
- 📋Short-answer questions: Define terms like 'yield', 'sustainable', or 'biological control'.
- 📋Practical-based questions: Describe an experiment to investigate the effect of fertiliser concentration on plant growth.
Command Word Expectations (WJEC)
What examiners look for when using specific command words in this specification
Give a balanced argument considering both advantages and disadvantages, then make a justified judgement or conclusion.
Give reasons or causes, showing how something happens. Use 'because' or 'therefore' to link ideas.
Use mathematical working to find a numerical answer. Show all steps and include units.
How Students Lose Marks (Examiner Pitfalls)
Common mark loss traps and how to write 100% full-mark answers
Step-by-Step Worked Solutions
Detailed solution breakdown for typical exam problems
Question: A farmer uses a new fertiliser that increases wheat yield from 5 tonnes per hectare to 6.5 tonnes per hectare. The cost of the fertiliser is £150 per hectare, and the price of wheat is £200 per tonne. Calculate the net financial gain per hectare from using the fertiliser.
- 1.Step 1: Calculate the increase in yield: 6.5 - 5 = 1.5 tonnes per hectare.
- 2.Step 2: Calculate the additional income from the increased yield: 1.5 tonnes × £200/tonne = £300.
- 3.Step 3: Subtract the cost of fertiliser: £300 - £150 = £150 net gain per hectare.
Question: Explain how genetically modified crops can help increase food yield while using fewer resources. (6 marks)
- 1.Step 1: Define genetically modified (GM) crops – crops with altered DNA to introduce desirable traits.
- 2.Step 2: Give an example, e.g., drought-resistant or pest-resistant crops.
- 3.Step 3: Explain how these traits reduce resource use: e.g., pest-resistant crops require fewer pesticides; drought-resistant crops need less water.
- 4.Step 4: Link to increased yield: with fewer losses to pests or drought, more of the crop survives, increasing yield per unit of resource.
- 5.Step 5: Mention sustainability: reduces environmental impact and costs for farmers.
- 6.Step 6: Conclude with a balanced view: potential concerns like biodiversity, but overall benefit.
Active Recall Memory Test
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Frequently Asked Questions
Common questions students ask about this topic
Before You Start
Prior knowledge that will help with this topic
- •Photosynthesis and factors affecting it (light, CO2, water, nutrients).
- •Plant nutrition and mineral requirements (e.g., nitrates, phosphates).
- •Basic genetics and variation (for understanding GM and selective breeding).
Study Guide Available
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Likely Command Words
How questions on this topic are typically asked
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