During an industrial accident at a dairy processing facility, a significant volume of raw milk is discharged into a local stream.
Name one major organic compound present in milk that acts as a nutrient source for saprobiontic microorganisms.
Explain the biological processes that lead to a decline in the stream's aquatic animal population following this discharge.
44 exam-style questions on Edexcel IGCSE Biology Human influences on the environment. Each one has a worked solution and a mark scheme showing where the marks go.