Answer:
the answer is a, i believe:)
Explanation:
hope this helps love:))
A, definitely A. The A example, only the tapeworm gains something, the mammal doesn't gain anything whilst in the other examples, both the organisms gain something, for example in B the remora can remove parasites which is good for the fish and provide the remora with food.
Answer:
Prokaryotes play several roles in the nitrogen cycle. Nitrogen-fixing bacteria in the soil and within the root nodules of some plants convert nitrogen gas in the atmosphere to ammonia. Nitrifying bacteria convert ammonia to nitrites or nitrates.... Denitrifying bacteria converts nitrates back to nitrogen gas.
