Question

What electron microscope technique is well suited to revealing the subunit structures of

such things as high-MW aggregates like viruses, ribosomes, multisubunit enzymes, cytoskeletal
elements, and protein complexes? The specimen in the resultant micrograph stands out by its relative
brightness on the viewing screen.
A) positive staining
B) negative staining
C) shadow casting
D) freeze fracture - freeze etch methodology
E) scanning electron microscopy

Answer 1

Negative staining, coupled with Transmission Electron Microscopy (TEM), is the technique best suited for highlighting the subunit structures of molecular complexes such as viruses and ribosomes by making them appear bright against a dark background. Option B.

Step-by-step explanation:

The electron microscope technique particularly well-suited for revealing the subunit structures of high-molecular-weight aggregates like viruses, ribosomes, multisubunit enzymes, cytoskeletal elements, and protein complexes is negative staining.

This technique involves staining the background around the particles, which results in the specimens standing out due to their relative brightness against the dark background on the viewing screen.

Transmission Electron Microscopy (TEM) is often employed in negative staining to attain high-resolution images of the specimen's ultrastructure.

So option B is correct.