The termite gut protist, Mixotricha paradoxa, has at least two kinds of bacteria attached to its outer surface. One kind is a spirochete that propels its host through the termite gut. A second type of bacteria synthesizes ATP, some of which is used by the spirochetes. The locomotion provided by the spirochetes introduces the ATP-producing bacteria to new food sources. Which term(s) is (are) applicable to the relationship between the two kinds of bacteria?

There are different ecological interactions between living organisms, depending on the benefits or harms that one or both species can receive as a result of their interaction. In this case, we talk about two bacteria that live on the surface of the Mixotricha paradoxa protist. These two bacteria have well-defined functions, one is responsible for locomotion and the other for the generation of energy in the form of ATP. In this interaction both organisms obtain benefits. When two organisms take mutual benefit from their interaction, it is called mutualism.

Other kinds of interactions are:

-Commensalism: An interaction that benefits an organism and the other organism is neither benefited nor harmed.

-Parasitism: One organism parasites the other to feed, causing damage to its host.

-Amensalism: One organism harms another without any benefit received.