Trophic levels and food security

4 lessons in Ecology.

20 exam questions · 40 marks

7.16 Trophic levels and pyramids of biomass Trophic levels from producers to apex predators, the role of decomposers, and how to draw and interpret pyramids of biomass, including why they are almost always pyramid shaped. Separate only AQA Edexcel OCR 5 questions 7.17 Biomass transfer and efficiency Why only about 1% of light energy is used by producers and only about 10% of biomass passes to the next trophic level, the losses by egestion, excretion and respiration, efficiency calculations, and why food chains are short. Separate only AQA Edexcel OCR 5 questions 7.18 Food security and farming What food security is and what threatens it, how intensive farming increases the efficiency of food production and the ethical concerns, sustainable fisheries with quotas and net sizes, and the use of fertilisers, biological control and hydroponics. Separate only AQA Edexcel OCR 5 questions 7.19 Biotechnology and food How modern biotechnology produces food: mycoprotein from the fungus Fusarium grown in fermenters, and genetically modified crops such as golden rice that provide more nutrients, with their benefits and concerns. Separate only AQA OCR 5 questions