posted by Sara .
What are he two processes that must occur to phosphates before they can cycle directly from organisms to the exchange pool and back to organisms?
Since this is not my area of expertise, I searched Google under the key words "phosphate cycle organisms" to get these possible sources:
In the future, you can find the information you desire more quickly, if you use appropriate key words to do your own search. Also see http://hanlib.sou.edu/searchtools/.
I hope this helps. Thanks for asking.