Compare and contrast the nature of the organisms in the fungal kingdom to those in the plant and animal kingdoms.
Like plants, fungi are sedentary and have cell-wall-bound cells. Unlike plants, fungi's cell walls are made from chitin, a polysaccharide containing nitrogen, not from cellulose. Also unlike plants, fungi are heterotrophs: fungi's cells do not contain chlorophyll, and, consequently, fungi must obtain nutrients in an already synthesized form. Unlike most animals, fungi cannot ingest particulate food-stuffs. As a result, they must live in or on their food. Fungi are, thus, parasitic or saprophytic. Whereas some parasitic fungi can absorb nutrients directly from their host, other parasitic fungi and all saprophytic fungi must secrete enzymes to digest surrounding food-stuffs which are then absorbed into the organism via root like rhizoids (found in larger fungi) or haustoria (found in smaller fungi).
