|MadSci Network: General Biology|
That's a really good question . . . and I'm not sure what your professor is looking for but I do know one thing they have in common: both can split dinitrogen. Dinitrogen, or N2, makes up 79% of our atmosphere and is colorless, odorless, non-toxic and incredibly stable. Sounds great so far, but the problem is that in the N2 form, nitrogen is not available for organisms to use. All living organisms NEED nitrogen - it is a key component of amino acids which are the building blocks of proteins. Nitrogen-fixing is the transformation of dinitrogen to biologically available nitrogen. The global nitrogen cycle is complex but it basically comes down to atmospheric nitrogen being *fixed*, take up by organisms and eventually turned back into dinitrogen. Without nitrogen fixation, the whole cycle would come to a halt and life as we know it would be over. In addition, lightning can split just about any atmospheric molecule including oxygen. If you care to, you can look up how ozone is created by lightning here at the Earth's surface. A good picture of what lightning is able to do to atmospheric molecules can be found at: http://sln.fi.edu/weather/lightning/science.html The text on this page is interesting but doesn't pertain to your question. I hope that helps!
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