Which type of microscope is most commonly used to examine viruses?

• A. Compound light microscope
• B. Dissecting microscope
• C. Transmission electron microscope
• D. Scanning tunneling microscope

Answer: (C)

Verified step by step guidance

1. Step 1: Understand the size range of viruses. Viruses are much smaller than most bacteria and cells, typically in the range of 20 to 300 nanometers, which is below the resolution limit of light microscopes.
2. Step 2: Recall the resolution limits of different microscopes. Compound light microscopes generally resolve objects down to about 200 nanometers, which is insufficient to clearly visualize viruses.
3. Step 3: Consider the capabilities of electron microscopes. Transmission electron microscopes (TEM) use electron beams with much shorter wavelengths than visible light, allowing them to resolve structures at the nanometer scale, suitable for viewing viruses.
4. Step 4: Differentiate between types of electron microscopes. TEM provides detailed internal structure images by transmitting electrons through thin samples, while scanning tunneling microscopes are used for surface atomic-level imaging, not typically for viruses.
5. Step 5: Conclude that the transmission electron microscope is the most commonly used microscope to examine viruses due to its high resolution and ability to visualize viral morphology.