Passage Summary: An essayist argues that Earth is a giant living thing because it regulates itself like a body, and points out that not having lungs doesn't mean you aren't alive, since insects don't have lungs either.

Conclusion: The Earth should be considered a living organism rather than just a physical object inhabited by creatures.

Reasoning: The Earth exhibits biological traits like metabolism and internal regulation, and the fact that it lacks lungs does not disqualify it, as other organisms like insects also lack lungs yet still respire.

Analysis: This is a 'Role in Argument' question, so we must determine how the specific mention of insects functions within the author's logic. The author first provides evidence for the Earth being an organism, then anticipates a potential objection—that Earth doesn't breathe—and uses the insect example to show that literal breathing is not a requirement for life. By showing that insects are organisms despite lacking lungs, the author effectively neutralizes a counterargument that would otherwise undermine the main conclusion.