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Exam-style practice

Pollution answer explanations

Review worked answers and explanations for Pollution. Aligned to Cambridge IGCSE Biology.

Answer explanations

Question 1 of 8

Review the answer support, then move sideways through the set.

Paper 3 structured question: Pollution

Paper 3Theory (Core)2 marks

Description

Pollution Effects

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

  1. a

    Describe how untreated sewage affects oxygen levels in aquatic ecosystems.

    [2]