Monday, 15 April 2013

4.10 describe the stages in the nitrogen cycle, including the roles of nitrogen fixing bacteria, decomposers, nitrifying bacteria and denitrifying bacteria

Nitrogen fixing bacteria turn nitrogen from N2 into ammonia.
Decomposers break down dead animals, urea and egested materials which releases nitrogen into the soil as ammonia.
Nitrifying bacteria convert nitrates into nitrogen.
Denitrifying bacteria break down nitrates into nitrogen which is then released into the atmosphere.

Here is a diagram to help explain:
File:Nitrogen Cycle.svg
commons.wikimedia

This animation is very helpful:
https://www.classzone.com/books/ml_science_share/vis_sim/em05_pg20_nitrogen/em05_pg20_nitrogen.swf

9 comments:

  1. This comment has been removed by the author.

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  2. I think that nitrifying bacteria convert nitrogen to nitrates, rather than the other way around. I'm fairly sure that nitrates turning into nitrogen is denitrifying bacteria.

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  3. nitrifying bacteria turn nitrites into nitrates

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  4. I love this youtube channel for science. Here is an animation on the Nitrogen cycle - https://www.youtube.com/watch?v=HOpRT8BRGtk

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  5. Nitrogen fixing turn nitrogen into ammonium ions, not ammonia...

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  6. The Biology Syllabus has changed…

    Here is a New blog for the 2017 Syllabus:

    http://igcse-biology-2017.blogspot.hk

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  7. more at

    http://igcse-biology-notes.blogspot.hk/2017/06/410-describe-stages-in-nitrogen-cycle_24.html

    ReplyDelete