Microbiology is the study of microorganisms, any organism too small to see without a microscope, including viruses, bacteria, and certain types of fungi. This is also a prerequisite course often taken before entering nursing school, because understanding the role that microorganisms play in human health is necessary to understand many other aspects of healthcare. Topics include microorganisms that cause and help prevent disease, including the emerging field of the human biome, and the microorganisms that are part of the human body. This course generally includes lab work as well as classroom work.

This is one of the most important nursing prerequisite classes because of how important microorganisms are to human health. It sets the groundwork for infection control, population health, clinical theory, and nursing practices.