Cycles

Question 1 of 10

In the nitrogen cycle, the conversion of ammonium compounds to nitrates is

Question 2 of 10

The source of energy for the water cycle is the

Question 3 of 10

Nitrogen-fixing bacteria are found in the root nodules of

Question 4 of 10

Lightning contributes to the nitrogen cycle by

Question 5 of 10

Carbon dioxide is removed from the atmosphere mainly by

Question 6 of 10

The life cycle of a mosquito includes egg, larva, pupa and

Question 7 of 10

The process by which nitrogen gas in the air is changed into nitrates in the soil by bacteria is

Question 8 of 10

In the nitrogen cycle, nitrifying bacteria convert

Question 9 of 10

The stage of a housefly's life cycle that feeds on rotting material is the

Question 10 of 10

In the water cycle, water vapour cools to form clouds by