[Campbell Biology P.143] What is the approximate resolution limit of a standard light micros... | Practice Question

What is the approximate resolution limit of a standard light microscope LM , and how much better is the practical resolution of a modern electron microscope EM compared to it?

  • A: 0.2 micrometers (µm); 10-fold better
  • B: 200 nanometers (nm); 100-fold better
  • C: 2 nanometers (nm); 100-fold better
  • D: 0.002 nanometers (nm); 1000-fold better

Explanation

The text states that a standard light microscope cannot resolve detail finer than about 0.2 micrometer µm , or 200 nanometers nm . It also mentions that modern electron microscopes usually cannot resolve structures smaller than about 2 nm across, which is a 100-fold improvement over the standard light microscope 200 nm / 2 nm = 100 .