the nitrogen cycle Flashcards
what is stage 1 of nitrogen cycle
nitrogen fixation
what is nitrogen fixation
converts nitrogen gas into nitrites then nitrates
what causes nitrogen fixation
lightning and nitrogen fixing bacteria found in soil and root nodules
what is stage 2 of nitrogen cycle
feeding
what happens in feeding
animals feed on plants that absorbed nitrates in the soil
what is stage 3 of nitrogen cycle
decomposition
what happens during decomposition
decomposers break down animal excretion and forms ammonia. this creates ammonium ions in soil
what is stage 4 of nitrogen cycle
nitrification
what happens during nitrification
nitrifying bacteria convert ammonium into nitrates
what is stage 5 of nitrogen cycle
denitrification
what happens during denitrification
denitrifying bacteria converts nitrates into nitrogen gas and releases back into atmosphere
what is the purpose of the nitrogen cycle
to allow plants and animals to absorb nitrogen as they cannot absorb it from atmospheric nitrogen
why is ammonia converted to ammonium after decomposition
to allow plants to absorb it as they can’t absorb ammonia
why is denitrification bad for plants
causes there to be less nitrates available in soil for absorption
what is the nitrogen cycle
how nitrogen is converted between different chemical forms by different processes
