Here's why:

* Microorganisms are too small to be seen with the naked eye. They are measured in micrometers (µm), which is one millionth of a meter.

* Microscopes magnify the image of the specimen, allowing us to see the tiny details of microorganisms.

* Different types of microscopes are used for different purposes, including:

* Light microscopes: Use visible light to illuminate the specimen.

* Electron microscopes: Use a beam of electrons to create a much higher magnification, allowing us to see even smaller structures.

So, a microscope is essential for any scientist studying microorganisms!