Animals have several characteristics that set them apart from other living things. Animals are eukaryotic and multicellular. Unlike plants and algae, which produce their own nutrients, animals are heterotrophic, internally.

Animals have several characteristics that set them apart from other living things. Animals are eukaryotic and multicellular. Unlike plants and algae, which produce their own nutrients, animals are heterotrophic, feeding on organic material and digesting it internally.