Derived characterCharacteristic that appears in recent parts of a lineage, but not in its older members.CladogramDiagram that shows the evolutionary relationships among a group of organisms.Molecular clockModel that uses DNA comparisons to estimate the length of time that two species have been evolving independently.DomainMost inclusive taxonomic category; larger than a kingdom.BacteriaDomain of unicellular prokaryotes that have cell walls containing peptidoglycans.EubacteriaKingdom of unicellular prokaryotes whos cell walls are made up of peptidoglycan.ArchaeaDomain of unicellular prokaryotes that have cell walls that do not contain peptidoglycan.EukaryaOrganism whose cells contain nuclei.ProtistaKingdom composed of eukaryotes that are not classified as plants, animals, or fungi.FungiKingdom composed of heterotrophs; many obtain energy and nutrients from dead organic matter.PlantaeKingdom of multicellular photosynthetic autotrophs that have cell walls containing cellulose.AnimaliaKingdom of multicellular eukaryotic heterotrophs whose cells do not have cell walls.Why do biologists use a classification system?To study the diversity of life. The classification system names organisms and groups them in a logical manner.What is binomial nomenclature?Each species is assigned a two-part scientific name.Which system of classification uses 7 taxonomic categories?Linnaeus's system of classification.What are the 7 taxonomic categories?From smallest to largest: species, genus, family, order, class, phylum, and kingdom.Organisms are now grouped into categories that represent what?Lines of evolutionary descent.How can the genes of many organisms that show important similaries at the molecular level be used?The similarities can be used as criteria for classification.What are the 6 kingdoms in the system of classification?Eubacteria, Archaebacteria, Protista, Fungi, Plantae, and Animalia.What are the 3 domains?Bacteria, Archaea, and Eukarya.