Which characteristic distinguishes fungi from plants?

Fungi are distinguished from plants primarily by their cellular structure, particularly the composition of their cell walls. In fungi, the cell wall is made of chitin, a polysaccharide that is also found in the exoskeletons of arthropods. This contrasts with plants, which have cell walls made of cellulose. The presence of chitin is a fundamental characteristic of fungi that sets them apart from the plant kingdom.

Other characteristics highlight differences as well. For instance, fungi do not engage in photosynthesis and are heterotrophic, meaning they obtain their nutrients by absorbing organic matter, unlike plants that are autotrophic and produce their own food through photosynthesis. Additionally, fungi do not reproduce using seeds; they typically reproduce through spores, further differentiating them from plants. This unique structural component of chitin in the cell walls is essential to understanding the biological classification and functional differences between these two kingdoms of life.