Answer: I believe the right answer is B) atmospheric nitrogen→bacteria→plants→animals. I'm pretty sure!
Sorry for answering a bit late, hope that helps! :-)
Answer:
It only allow certain material to enter the cell
Lichens have been described as "dual organisms<span>" because they are symbiotic associations between two (or sometimes more) entirely different types of microorganism - a fungus (termed the mycobiont) a green alga or a cyanobacterium (termed the photobiont).
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