WorksheetsIGCSE Nitrogen Cycle & Eutrophication
Total questions: 20
Worksheet time: 20mins
Which of the following is true about nitrogen?
It is the most common gas in air
It is unreactive as a gas
It is needed to make all proteins
It is taken up as a gas through the roots of plants
What is true of nitrogen fixation?
It converts nitrogen gas to nitrates
It is carried out by bacteria but can also happen by lightning
It converts ammonia to nitrates
It converts nitrogen gas to ammonia
Which is true of nitrification?
It converts ammonia to nitrates
It converts nitrates to nitrogen gas
It is carried out by bacteria
It requires nitrogen gas
Which is true of denitrification?
It converts ammonia to nitrates
It can occur due to lightning
It converts nitrates to nitrogen gas
It benefits the plant
How can nitrogen become part of animal proteins?
Animals inhale nitrogen gas
Animals feed on plants
Animals eat carbohydrates
Animals inhale nitrous oxide gas
In the nitrogen cycle, in what form do decomposers release nitrogen from dead plants and animals?
nitrogen gas
ammonia
nitrate ions
nitrous oxide gas
Which of the following stages in the nitrogen cycle require bacteria?
nitrogen fixation
nitrification
decomposition
denitrification
What can be a source of nitrates for eutrophication in rivers?
fertilisers
plastic bottles
paper
sewage
What is the very next thing that happens after fertilisers enter a river in eutrophication?
Fish die due to a lack of oxygen
Plants below the surface die due to a lack of sunlight
The number of aerobic bacteria increases
Fast growth of plants
What is the very next thing that happens after fast growth of plants in eutrophication?
Fish die due to a lack of oxygen
Plants below the surface die due to a lack of sunlight
The number of aerobic bacteria increases
Plants on the surface die due to too much sunlight
What is the very next thing that happens after plants die in eutrophication?
Fish die due to a lack of oxygen
The number of plants increases again as they have more access to sunlight
The number of aerobic bacteria increases
The number of nitrates in the river increases again
In eutrophication, what directly causes the death of fish?
The plants use up oxygen in respiration
The fish are poisoned by high CO2 levels
Bacteria use up oxygen in respiration
The fish use up oxygen in respiration
In eutrophication, what does 'algal bloom' refer to?
The rapid increase in the number of bacteria
The rapid increase in the number of plants
The rapid decrease in the number of fish
The rapid increase in the amount of nitrates in the river
Which of the following processes is/are part of the water cycle?
precipitation
evaporation
nitrification
transpiration
In the water cycle, how does water vapour in the air form water droplets in the clouds?
evaporation
precipitation
condensation
transpiration
What are the main gases that cause acid rain?
nitrogen oxides
carbon dioxide
sulphur dioxide
ozone
What is the main role of catalytic converters in cars?
Breaking down sulphur dioxide before it is released
Mixing sulphur dioxide with water
Breaking down nitrogen oxides before they are released
Mixing nitrogen oxides with water
Which of the following gases are responsible for turning rain acidic?
carbonic acid
hydrochloric acid
sulphuric acid
nitric acid
Which of the following are effects of acid rain?
Fish produce thick mucus that blocks their gills
Kills aquatic plants
Kills aquatic animals
pH of rivers increases
What do power stations have in their chimneys to neutralise acidic gases before they can escape?
limestone
chlorine
water
nitrogen
