Chp. 17 Classification Characteristics of Living Things Living things are organized (possess structures for every function) Living things make more living things (Reproduction) Living things change during their lives (growth- increase in the amount of living material & formation of new structures) Living things adjust to their surroundings Stimulus- any condition in the environment that requires an organism to adjust Response- reaction to stimuli Adaptation- enables a response to stimuli (Ex: change in body temp.) Homeostasis- regulation of an organisms internal environment to maintain conditions Energy- ability to do work ALL LIVING THINGS REQUIRE AN ENERGY SOURCE Evolution- change over time CLASSIFICATION Grouping together of objects or info based on similarities Taxonomy- branch of biology dealing w/grouping & naming of organisms based on: 1. Physical Similarities 2. Chemical Makeup (DNA) 3. Evolutionary Relationships ARISTOTLE Greek philosopher Developed 1 st method of classification He only classified 2 groups- Plant & Animal CAROLUS LINNAEUS Swedish botanist Selected physical characteristics & evolutionary relationships for classification Binomial Nomenclature- invented by Linnaeus, 2 word naming system for species First word is the Genus, second word is the Species (descriptive word) Ex: Homo sapien Scientific names are written in Latin Underlined or in italics 1 st letter is capitalized for the first word, rest are lower case Golden Hamster Mesocricetus auratus Mesocricetus brandti RATS Rattus norvegicus- Norway Rat Rattus rattus- Roof Rat Taxa- organisms grouped into a series of categories Species- most specific (smallest) Genus- group of closely related species Family- group of closely related genera (genus) Ex: Bobcats & lynx are in the same cat family Felidae but have a different genus Order- group of related families Class- group of related orders Phylum- group of related classes Kingdom- group of related phyla (largest) King Phillip came over for good soup Phylogeny Evolutionary history of a species Based on comparative relationships of structures & comparison of modern life forms w/fossils Cladistics System of taxonomy that reconstructs relationships based on similarities Cladogram- branching diagram that shows evolutionary relationships 3 DOMAINS 1. DOMAIN BACTERIA 2. DOMAIN ARCHAEA 3. DOMAIN EUKARYA DOMAIN BACTERIA Bacteria- microscopic, unicellular, prokaryotic, appeared 3.5 bya, 10,0000 species. Ex: Streptococcus (strep throat) Cell walls contain peptidoglycan DOMAIN ARCHAEA Cell walls do not contain peptidoglycan Extremophiles- live in harsh environments Gave rise to eukaryotic cells DOMAIN EUKARYA Membrane bound nucleus and organelles 4 Kingdoms Protista- Eukaryotic, uni/multicellular, live in water, appeared 1 bya, no complex organ system Ex: Amoeba, Paramecium, seaweed Fungi- consumers, dont move, uni/multicellular, heterotrophic, eukaryotic, decomposers (mushroom, mold, yeast) Appeared 400 mya ago Plants- stationary, multicellular, eukaryote, photosynthesis, cell walls, have organ systems, 1 st plant fossil dated 400 mya Plants dont fossilize well Animalia- multicellular, consumer, no cell walls, organ systems, 1 st appeared 700 mya.