Learning objective

Explain how untreated sewage and excess fertilizers impact aquatic ecosystems.

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Exam focus

Cambridge IGCSE BiologyHuman influences on ecosystemsCore content

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Quick explanation

This point belongs to Pollution, especially Pollution outcomes.
You need to be able to explain how untreated sewage and excess fertilizers impact aquatic ecosystems.
The key ideas to know are Describe.
Use the linked flashcards and practice questions to check recall, then practise applying the idea in an exam-style answer.

Key concepts

Describe

Why it matters

This objective helps connect Pollution outcomes to exam-style questions, flashcards, and revision notes for Pollution.

Revision tools

Flashcards10 linked cards

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Practice Questions7 linked questions

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Paper 3Theory (Core)2 marks

Description

Untreated sewage and excess fertilizers enter a lake, causing changes in oxygen levels and aquatic life.

a
Describe how untreated sewage affects oxygen levels in aquatic ecosystems.
Your answer
Aim for approximately 2 distinct marking points.
[2]

Revision notestopic notes

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