An orchard food chain is:
apple tree leaves → aphids → ladybirds
The ladybirds are at trophic level 3 and have a total biomass of 18 kg.
For each step in the food chain, about 10% of the biomass is passed to the next trophic level.
What biomass would you expect for the apple tree leaves at trophic level 1?
180 kg
18 000 kg
0.18 kg
1800 kg
103 exam-style questions 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. Each one has a worked solution and a mark scheme showing where the marks go.