Classification

• Why do we need to classify species on Earth?

  To organize millions of different species
• How did our ancestors classify species?

  Based on their physical appearance
• What is a problem with naming species based on appearance?

  Different names for the same species exist
• Why are simple names insufficient for classification?

  They don't indicate species' relationships
• Who proposed the Linnaean system of classification?

  Carl Linnaeus
• What does the Linnaean system group species into?

  Kingdom, phylum, class, order, family, genus, species
• What language are the names in the Linnaean system primarily in?

  Latin
• What is the binomial naming system?

  It uses genus and species names
• How would you write the scientific name for humans?

  Homo sapiens
• What is the correct formatting for scientific names?

  Italicize and capitalize the genus name
• What did Carl Woese propose in the 1990s?

  The three domain system of classification
• What are the three domains proposed by Woese?

  Eukaryota, bacteria, archaea
• What does the domain Eukaryota include?

  Organisms with eukaryotic cells
• What are bacteria?

  Single-celled prokaryotic organisms
• What is unique about archaea?

  They thrive in extreme conditions
• How are evolutionary trees useful?

  They show evolutionary relationships
• How do evolutionary trees illustrate common ancestors?

  By showing where lines split
• What do scientists compare to learn about species relationships?

  Structure and DNA of species
• What is the order of classification groups in the Linnaean system?

  • Domain
  • Kingdom
  • Phylum
  • Class
  • Order
  • Family
  • Genus
  • Species
• How do the Linnaean system and three domain system differ?

  • Linnaean: seven levels of classification
  • Three domain: three higher categories above kingdoms
  • Both systems aim to classify organisms