How Is It That Scientists Didn't Know Until Fairly Recently

question 26

Multiple Choice

How is it that scientists didn't know until fairly recently that humans carry around whole ecosystems of bacteria?

• A) We didn't have strong enough microscopes to see bacteria.
• B) They weren't looking for them.
• C) The bacteria don't grow well in the lab, and only lately have we had the technology to identify bacterial species by RNA.
• D) The bacteria don't grow well in the lab, and only lately have we had the technology to see them.
• E) Bacteria have especially complex RNA, so it took awhile use that to identify species.

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Definitions:

Characteristics

Distinguishing traits, qualities, or properties of an individual or thing.

Scatter Diagram

A graphical representation using dots to show the relationship between two variables, often used to identify patterns or trends.

Nominal Variables

Variables classified into categories that cannot be ordered or ranked; they are used to label or name categories or groups.

Relationship

The manner by which two or more ideas, items, or individuals are linked, or the condition of linkage.