An electron microscope would be used if

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 .

humans can cause extinction of a species through overharvesting, pollution, habitat destruction, introduction of invasive species (such as new predators and food competitors), overhunting, and other influences. explosive, unsustainable human population growth is an essential cause of the extinction crisis.

explanation:

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