Why does bacteria and sewage cause the death of fish?

This question can be broken down. Sewage contains organic matter which can be broken down, and bacteria need nutrients which they can get from digesting organic matter. Any form of digestion with aerobic bacteria will use up oxygen, as oxygen is used in respiration to provide energy for this digestion. From this, oxygen levels in the river will fall and so there is not enough oxygen for the fish, meaning they cannot respire and so die.

HM
Answered by Hishaam M. Biology tutor

3517 Views

See similar Biology GCSE tutors

Related Biology GCSE answers

All answers ▸

Explain the process of natural selection.


What are the functions of xylem and phloem?


Explain how vaccination prevents illness in an individual


What do you understand by gene cloning?


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

MyTutor is part of the IXL family of brands:

© 2025 by IXL Learning