Nitrogen Cycle

Question 1

Nitrogen cycle

Answer 1

The nitrogen cycle transforms and circulates nitrogen in various forms through Earth’s spheres

Question 2

Atmospheric nitrogen fixation

Answer 2

Lightning strikes generate energy to separate nitrogen gas (N2) into nitric oxide (NO) and nitrogen dioxide (NO2) which is transported through rain

Question 3

Assimilation

Answer 3

Plants and some microorganisms take up ammonium (NH4+) and nitrate ions from the soil to use in cell processes

Question 4

Consumption

Answer 4

Animals acquire organic nitrogen by consuming plants or other animals

Question 5

Ammonification

Answer 5

Decomposers (bacteria and fungi) break down nitrogen compounds and Converts them to ammonia or ammonium ions which is then released into the soil

Question 6

Volcanic eruptions

Answer 6

Heat and pressure created by eruptions leads to transformation of atmospheric nitrogen into nitrogen oxides

Question 7

Denitrification by bacteria

Answer 7

Denitrifying bacteria convert nitrate (NO3-) and nitrate (NO2-) ions into nitrogen gas

Question 8

Nitrogen fixation by bacteria

Answer 8

Atmospheric N2 is converted into ammonia or ammonium ions by nitrogen-fixing bacteria found in the soil

Question 9

Nitrification

Answer 9

Ammonia (form nitrogen fixation) is converted to nitrate ions by nitrifying bacteria. Nitrite ions are then oxidized into nitrate ions by other nitrifying bacteria (Nitrobacter)