Nitrogen Cycle

Question 1

How does ammonia get converted into nitrites (NO2-)?

Answer 1

Via nitrification by nitrosomonas.

Question 2

How does Nitrogen in the atmosphere (N2) become ammonia (NH3+)?

Answer 2

Via Nitrogen fixation
> Mutualistic nitrogen-fixing bacteria - in root nodules in legumes e.g. Rhizobium
> Free-living nitrogen-fixing bacteria e.g. Azotobacter

Question 3

How are nitrites (NO2-) converted into nitrates (NO3-)?

Answer 3

Via nitrification by nitrobacter.

Question 4

How do Nitrates get converted into nitrogen gas into the atmosphere?

Answer 4

Via denitrification
e.g. Pseudomanas

Question 5

How does dead/decaying organic matter get converted into ammonia?

Answer 5

Via ammonification by decomposers - bacteria and fungi (saprophytes)

Question 6

How does nitrogen in the atmosphere get converted straight into nitrates?

Answer 6

Via lightning - splits up the N2 which reacts with oxygen in the air

Question 7

How does nitrogen get into plants?

Answer 7

Plants uptake nitrates from the soil via active transport for photosynthesis.

Question 8

How does nitrogen get into animals?

Answer 8

Nitrogen gets transferred from plants to animals through the food chain