A tundra food chain is:
moss → springtails → ground beetles
A large biomass of springtails is needed to support a much smaller biomass of ground beetles.
Which statement explains this?
The ground beetles use respiration to turn most of the springtail biomass into new beetle tissue
The springtails make biomass by photosynthesis, so they have more biomass than the ground beetles
Much of the biomass the ground beetles absorb is used in respiration and lost as carbon dioxide and water
Most of the biomass the ground beetles absorb is lost as urea in their faeces
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.