Classification

• Describe the domain Archaea

  • Consists of primitive microorganisms
  • Contains extremophiles - adapted to live in extreme conditions e.g. hot springs
• Describe the domain Bacteria


  Consists of true bacteria e.g. E.coli
• Which domains do prokaryotic organisms belong to?

  Archaea and Bacteria
• Which domain do eukaryotic organisms belong to?

  Eukarya
• Describe the three domains system of classification

  • Organisms are initially divided into an extra three groups: Archaea, Bacteria, Eukarya
  • domain, kingdom, phylum, class, order, family, genus, species.
• What advancements in science have led scientists to reconsider the five kingdoms classification system?


  • Microscopes
  • Biochemistry
  • DNA and RNA analysis
• Traditionally, organisms were grouped based on similarities and differences in their anatomy and behaviour. What is the problem with this?


  • Organisms that are not closely related may look alike and behave similarly if they live in the same environment e.g. sharks and dolphins
  • Some closely related species may look very different if they live in different habitats e.g. queen ants, worker ants
• What happens to the number of organisms in each taxon as you move down the hierarchy?

  The number of organisms in each taxon group decreases
• Name the five kingdoms

  Animals, plants, fungi, protists, prokaryotes
• What is taxonomy?


  The classification of organisms into taxa: kingdom, phylum, class, order, family, genus, species.
• What is classification?


  The organisation of organisms into groups