Which of these species is indicative of clean water?None of the answer alternatives.Sludge wormBloodwormStonefly nymph

Which of these species indicates very polluted water?Mayfly larvaFreshwater shrimpTubifex wormMayfly nymph

Look at the chart below. We know that the water in Dwyer Lake is polluted because of the presence of sludgeworms. In this case, sludgeworms are a... what?

Which of the following living microorganism is used as an indicator of water pollution

Which of the following is not an abiotic factor that influences the distribution of organisms?Availability of foodWaterAtmospheric gasesTemperature2Which of the following is an ‘indicator species’ of oxygenated water?Mayfly larvaeLichenRed-tailed maggotSludgeworms3Why does the bright red colour of sludgeworms mean they can thrive in water containing low levels of oxygen?It attracts matesIt warns off predatorsIt indicates a high concentration of haemoglobinIt provides camouflage4Lichens are plant-like organisms that grow in exposed places such as rocks or tree bark. If few or no lichens are growing in a specific area, what might this indicate? The air is pollutedA new pathogen has been introducedA new predator has been introducedThe air is clean

Polychaetes are annelid worms that live in the ______ habitat.Multiple choice question.terrestrialmarinefreshwater