Viruses can be visualized using an electron microscope. The electron microscope shoots electrons at the virus and interprets how they interact with the virus. A computer can generate an image from this information. If you shoot electrons at the virus from all different angles you can generate a 3D image.

Viruses can also be visualized using crystallography. For this method to work you need to isolate the virus in liquid and then evaporate the liquid and form crystals. The crystals are exposed to X-rays and the pattern that X-rays produce when passed through the crystal can be used to interpret the shape of the virus. DNA can also be visualized using electron microscopy and X-ray crystallography.

However, when scientists are working with viruses and DNA they do not need to regularly visualize them using these methods. If you see a scientist working with viruses and DNA they will be moving very small amounts of liquid into other small amounts of liquid. There are ways to test if viruses and DNA are present in the liquid that do not require visualization. The method for introducing DNA into viruses depends on the type of virus, but in general, it involves mixing a liquid that contains the virus with a liquid that contains DNA with a particular sequence and then exposing the mixture to the right chemicals and environment. This will cause the virus to “take up” the DNA.

For more information on how scientist study viruses, here is a link to five techniques that can be used to visualize viruses and the effect they have on cells.