Question

are focused by magnetic fields. two types of electron microscopes are: a) transmission electron microscopes make it possible to explore cell structures and large protein molecules. - they can only be used with non - living specimens. b) scanning electron microscopes use a pencil - like beam of electrons to scan over the surface of a specimen. - they produce three - dimensional images. - they can only be used with i cells or tissues.

Explanation:

Transmission electron microscopes (TEM) are used for exploring cell - structures and large protein molecules and require non - living specimens. Scanning electron microscopes (SEM) scan the surface of a specimen with an electron beam, produce 3D images and are used with non - living cells or tissues.

Answer:

A. Transmission electron; non - living
B. Scanning electron; surface; non - living