Some digestive adaptations involve mutualistic __, a mutually beneficial interaction between two species.
o Much of the chem energy in herbivore diets comes from the __ of plant cell walls, but animals do not produce enzymes that hydrolyze cellulose. Instead many vertebrates house large populations of mutualistic bacteria and protists in fermentation chambers in their alimentary canals. These microorganisms have enzymes that can digest cellulose to simple sugars and other compounds that the animal can absorb. In many cases, the mcroorganisms also use the sugars from digested cellulose to produce a variety of nutrients essential to the animal, like vitamins and amino acids.