Two species of freshwater snail feed on the same species of algae. Each snail eats 8.0 g dry mass of algae.
| Snail species | Dry mass of algae eaten in g | Dry mass of faeces produced in g |
|---|---|---|
| A | 8.0 | 2.0 |
| B | 8.0 | 1.2 |
Calculate the percentage of the biomass eaten by snail species A that is lost in its faeces.
Explain why the efficiency of biomass transfer from the algae to snail species B may be greater than the efficiency of transfer to snail species A.
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.