3

CHAPTER

47

Observing

Microorganisms

Growing up you were probably forever being told to wash your hands so you
would not become infected by germs. You probably complied only to stay out
of trouble because no matter how well you focused on your hands, you never
saw a germ on them. Today you realize that a germ is a microorganism, one of
themany microorganisms that surround us. Microorganisms cannot be seen with
the naked eye, but you can see them with the aide of a microscope. In this chap-
ter, you’ll learn how to view microorganisms under a microscope.

Size Is a Matter of Metrics

We could describe the size of a microorganism in a variety of ways. A micro-
organism is small, tiny, and miniscule. It is smaller than a human hair. Millions
of them can fit on the head of a pin. All of these words give you an idea of how

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