AQA GCSE Combined Science Trilogy · 8464
Specification 4.7.3.2, 5.10.1.3 · Paper 2, Paper 4
Revise: Waste Management and PollutionUntreated sewage contains organic matter that microorganisms can break down. As these microorganisms feed and multiply, they use dissolved oxygen in aerobic respiration. Oxygen levels in the water fall, so fish and other aquatic animals may no longer have enough oxygen for respiration and can die.
- Revise: Waste Water Treatment
Waste water containing human waste and other domestic waste carried through sewers.