Question

What is the reason that a modern electron microscope (TEM) can resolve biological images to the subnanometer level, as opposed to tens of nanometers achievable for the best super-resolution light microscope?

A) The focal length of the electron microscope is significantly longer.
B) Contrast is enhanced by staining with atoms of heavy metal.
C) Electron beams have much shorter wavelengths than visible light.
D) The electron microscope has a much greater ratio of image size to real size.
E) The electron microscope cannot image whole cells at one time.

Answer 1

Modern electron microscopes use electron beams with wavelengths much shorter than visible light, enabling them to resolve images at the subnanometer level, vastly superior to optical microscopes.

Step-by-step explanation:

The reason that a modern electron microscope (TEM) can resolve biological images to the subnanometer level, as opposed to tens of nanometers for the best super-resolution light microscope, is due to the fact that electron beams have much shorter wavelengths than visible light. With wavelengths of approximately 0.005 nm, electrons can produce images with significantly better resolution. This allows electron microscopes to magnify and resolve structures far beyond the capabilities of optical microscopes, enabling the observation of details as small as individual atoms and the structure of cell nuclei.