Biology 5090 · O Level · Effects of humans on ecosystems

Effects of humans on ecosystems — practice question

A lake has been contaminated by sewage. How will the water in this lake differ from water that has not been polluted?

  • Abacteria: more; nitrates: more; oxygen: more
  • Bbacteria: more; nitrates: more; oxygen: less
  • Cbacteria: more; nitrates: less; oxygen: more
  • Dbacteria: less; nitrates: more; oxygen: more

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