Question

An electron microscope would be used if _____.

Answer 1

Answer:

For viewing ultra- structure

Explanation:

When any object, substance or biological specimen is so small that it cannot be viewed through normal optical telescopes then it become essential to use electron microscope. Thus electron microscope are used for inspecting wide range of  ultra-structure

In an electron microscope , a beam of electron is thrown on the object which makes it advantageous over and above normal optical microscope which have certain limitations due to the limitations associated with light .

Answer 2

 a sample was too small to be seen with an optical microscope 

lighter or darker has nothing to do with microscope. 
cell structure is easily visible with optical telescope.
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