Animals as a category have several characteristics that generally set them apart from other living things. Animals are eukaryotic and usually multicellular, which separates them from bacteria, archaea, and most protists. They are heterotrophic, generally digesting food in an internal chamber, which separates them from plants and algae. They are also distinguished from plants, algae, and fungi by lacking cell walls.
Animals as a category have several characteristics that generall!y set them apart from other living things. Animals are eukaryotic and usually multicellular, which separates them from bacteria, archaea, and most protists. They are het!erotrophic, generally digesting food in an internal chamb?er, which separates them from plants and algae. They are also distinguished from plants, algae, and fungi by lacking cell walls.