Worksheets on AQA GCSE Biology 7.4 Trophic levels in an ecosystem, covering 7.4.1 Trophic levels, 7.4.2 Pyramids of biomass, and 7.4.3 Transfer of biomass, 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.