Worksheets on Edexcel GCSE Biology 9.2 Energy transfer and biodiversity, covering 9.2.1 Energy transfer between trophic levels, 9.2.2 Efficiency of energy transfers, 9.2.3 Human interactions and biodiversity, 9.2.4 Benefits of maintaining biodiversity, and 9.2.5 Biological factors affecting food security, with answers. Print them, or work through one on screen. Write your working straight onto the paper and Genie marks it question by question against the mark scheme.