Answer:
By the structure of their cell wall
Step-by-step explanation:
Fungus cell contain cell wall with a chitin in it. That differs them from animal cell that doesn't have cell wall, but also differs them from plant cell wall which contains cellulose.
Fungus is a eukaryotic kingdom which contains microorganisms such as yeasts and molds, but also macroscopic forms such as mushrooms.
Fungus are heterotrophic organisms, often decomposers with high biodiversity.