Virus Structures

Viruses attack cells and force them to make many new viruses, often killing the cell in the process. Some viruses are very simple, such as the protein capsids that surround a short strand of RNA or DNA. More complex viruses inject the cell with a viral genome capable of encoding proteins to fight the cell's defenses.

Most viruses are much smaller than cells–the ones shown here are all drawn at approximately 900,000x magnification, ranging from less than 30 nanometers to over 500 nanometers in diameter (1 nanometer = 1 billionth of a meter).