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The nitrogen cycle
Nitrogen use in the soil
Nitrogen release to air
The nitrogen cycle - Quiz

The nitrogen cycle - Quiz

Answer each question below, then choose Check answers to see your score. You can reveal the correct responses after marking.

1 What is the nitrogen cycle?

A rocket-powered bicycle The exchange of nitrogen between air, sea and land The increase of greenhouse gases

2 What proportion of the atmosphere is Nitrogen?

10 % 24 % 78 % 90 %

3 What name describes nitrogen passing from air to soil?

Hydrogenation Nitroglycerine Nitrogen fixing Nitrogen loosening

4 What is a legume, also called a 'leguminous' plant?

A plant with broad green leaves A plant with root nodules with nitrogen fixing bacteria A plant with roots passing up into the air A long and leggy plant

5 Which of these natural events can convert nitrogen in air to nitrogen useable by plants?

Tropical monsoon Bright sunlight Hail Lightning

6 Where is most nitrogen stored in soils?

In the sand particles In the silt particles In the clay particles In organic matter In the air gaps between particles In soil water

7 What is 'denitrification'?

The release of nitrogen from the soil into the air The reduction of atmospheric nitrogen levels The burning of fossil fuels, like petrol The growth of green plants

8 How can farmers increase levels of nitrogen in their soil?

By adding nitrogen-based fertilisers By adding pesticides By ploughing the soil By irrigating the soil

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