Recall the three domains of life: Archaea, Bacteria, and Eukarya. These domains categorize all living organisms based on cellular structure and genetics.
Understand that fungi are complex organisms with membrane-bound organelles, including a defined nucleus, which is a characteristic of eukaryotic cells.
Recognize that Archaea and Bacteria are domains consisting of prokaryotic organisms, which lack a nucleus and membrane-bound organelles.
Note that viruses are not classified within any domain of life because they are not considered living cells; they require a host to replicate.
Conclude that since fungi have eukaryotic cell structures, they belong to the domain Eukarya.