Levels of Classification - Linnaean System of Classification o Carol Linnaeus o Based on similar structures o Latin names o Started with 2 kingdoms but expanded to 5 kingdoms Animals, plants, fungi, Protoctista, and monerao Kingdom, phylum, class, order, family, genus, species - Rules for Scientific Nameso Each name consists of two parts  Italicized o Genus is always capitalized while species is noto The genus can be abbreviated o Example: Escherichia coli (E. coli) Escherichia = genus, coli = species  Named after discoverer; coli indicates it is present in the colon- Defining Species for Prokaryotes o Collection of bacterial strains sharing stable properties  Very vague, can be confusingo Pure culture = growth of a single species or strain in the labo Strain = genetically different cells within a species  Analogy: Bacterial species are like dogs in general while bacterial strains are like breeds of dogs o Clone = population of cells that come from a single cello Colony = collection of cells on a solid medium that come from one cell- Strain Nameso Escherichia coli O157: H7Escherichia coli = species nameO157:H7 = strain designationO = LPS O-antigen157 = antigen numberH = flagellin7 = antigen number-Division of Bacteria and Archaeao Carl Woese Compared DNA between species Examined rRNA genes-Why rRNA?o Molecular chronometero All cells have rRNA genes, they don’t change quickly, and if they do change, the changes aren’t lethalChanged phylogenetics -Study of evolutionary history of organisms Created 3 domains: bacteria, archaea, and