A large amount of sewage enters a river and many of the fish die. Sewage contains bacteria and organic material. Explain why the fish died.
Bacteria in the water decay organic matter in sewage -> respire aerobically -> uses the O2 in the water and reduces O2 concentration -> fish have less O2 to aerobically respirate -> fish die
CH
Related Biology GCSE answers
All answers ▸Compare the similarities and differences between animal and plant cells? (6 marks)
describe the function and structure of the cardiovascular system
Explain active transport and give an example to demonstrate this in both plants and animals
Describe the process which is used by plants to make food?