Answer:
1.micro-organisms play a primary role in regulating biogeochemical systems in virtually all of our planets environment.microbes participate in essential biogeochemical cycling event's such as carbon and nitrogen fixation
2.interaction between two different organisms living in a close physical association, typically to the advantage of both
3.mutualism:both partners benefit. an example of mutualism is the relationship between Egyptian plover and the crocodile, the plover eats a meal and the crocodile gets its teeth cleaned. coincidentally the Egyptian plover is also known as the crocodile bird.
commensalism:only one specie benefits why the other is neither helped not harmed. eg is the remora fish are very bony and have a dorsal fin that acts like a suction cup the remora fish gets a meal while the host gets nothing. selfish, sure but neither gets hurt
parasitism:one organism(the parasite)gains while the other(the host) suffers the deer thick is a parasite it attaches to a warm-blooded animal and feed on its blood. the thick benefits from the animal blood and unfortunately, the animal suffers from the loss of blood and nutrients and may get sick
4.