An electron microscope uses a beam of electrons to illuminate a specimen
body tube
body tube
the nucleus
eyepiece
Parfocal
the invention of the microscope makes cell study possible because Robert Hooke described his observation with a simple lens of thin slices of cork and then he observed a cell wall and that is how cells get there name.
The different levels of magnification. It makes it easier for you to recognize the magnification you want without having to read the numbers on the side.
Microscope
A microscope magnifys or makes things look bigger than they are.
The arm makes carrying around a microscope easier.
The transmission electron microscope operates on the same principle as the light microscope but uses electrons instead of light. What you can see with a light microscope is limited by the wavelength of light. Transmission electron microscopes use electrons as "light source" and their much lower wavelength makes it possible to get a resolution a thousand times better than with light microscope.