WRITING TASK 1
Process diagram
You should spend about 20 minutes on this task.
The diagram below shows how nitrogen circulates through the air, soil and living things.
Summarise the information by selecting and reporting the main features, and make comparisons where relevant.
Write at least 150 words.
- 1Nitrogen fixationBacteria turn atmospheric nitrogen into ammonia
- 2NitrificationOther bacteria convert ammonia to nitrates
- 3Plant uptakeRoots absorb nitrates from the soil
- 4Animals eat plantsNitrogen passes to herbivores and predators
- 5Waste and deathExcretion and decay return nitrogen to the soil
- 6AmmonificationDecomposers release ammonia
- 7DenitrificationBacteria convert nitrates back into nitrogen gas
1Nitrogen fixationBacteria turn atmospheric nitrogen into ammonia
2NitrificationOther bacteria convert ammonia to nitrates
3Plant uptakeRoots absorb nitrates from the soil
4Animals eat plantsNitrogen passes to herbivores and predators
5Waste and deathExcretion and decay return nitrogen to the soil
6AmmonificationDecomposers release ammonia
7DenitrificationBacteria convert nitrates back into nitrogen gas
The cycle then repeats from stage 1.