4 Answer all the questions. SECTION A – Module B2 1
Look at the pyramid of numbers. parasites platypus fish water fleas aquatic plants
(a) (i)
Sketch the pyramid of biomass for the same food chain.
[1] (ii)
Explain why this pyramid of biomass is a different shape. ........................................................................................................................................... ...................................................................................................................................... [1]
(b) When the platypus dies, nitrogen from the decomposing platypus is recycled. The first stage involves decomposers converting proteins into ammonia. The ammonia is then converted so that it can be used by plants. Explain how ammonia is converted in the nitrogen cycle. ................................................................................................................................................... ................................................................................................................................................... .............................................................................................................................................. [2]
Š OCR 2013