C2 classification

• Binomial system of nomenclature


  Each species is assigned with a two-part name (scientific name) that is generally derived from Greek or Latin words
• Before the 18th century, each organism has a lengthy descriptive name
• As more people studied nature, it became obvious that a butterfly's wings were very different structures than a bird's wings
• Binomial system


  Simplified the classic scientific classification, introduced by Carolus Linnaeus in the 18th century
• Importance of binomial system

  • Allows biology to become an international language
  • Eliminates repeated study done on the same organism
• Errors in the writing of binomial names: Panthera Tigris, Tapirus indicus, Macaca fascicularis
• Taxonomy


  Branch of biology dealing with the identification, naming and classifying of organisms
• Taxon


  Taxonomic categories that show degrees of similarities among organisms, from the narrowest (species) to the broadest (kingdom)
• Species


  • A group of similar organisms that can interbreed in their own natural environment
  • Reproductively isolated from other organisms
• Importance of taxonomy


  Easier to retrieve information, predict characteristics of new-found species, and explain evolutionary relationships
• From the time of Aristotle to the mid 19th century, all living things were divided into two kingdoms: plant and animal
• After the development of microscope, scientists faced difficulties in classifying microorganisms like Euglena that have characteristics of both plants and animals
• In 1866, Ernst H. Haeckel created a third kingdom, the Protista, including bacteria, algae, protozoa, fungi, and sponges
• In 1937, a French marine Biologist Eduord Chatton suggested the terms 'procariotique' and 'eucariotique'
• In 1956, Lynn Margulis and H.F. Copeland proposed a four-kingdom system: Monera, Protoctista, Plantae and Animalia
• In 1969, R.H. Whittaker proposed a five-kingdom system by separating the Protoctista into two kingdoms - Protista and Fungi
• In the 1970s, Carl R. Woese proposed the three-domain classification system based on RNA analysis, separating Archaea and Eubacteria
• Five-kingdom classification system


  • Kingdom Monera: Prokaryotic organisms like eubacteria, cyanobacteria and archaebacteria
  • Kingdom Protista: Simple eukaryotes, some resemble fungi, plants and animals
  • Kingdom Fungi: Mostly multicellular, heterotrophic, form spores but not seeds
  • Kingdom Plantae: Multicellular, contain chlorophyll, include seedless and seed-bearing vascular plants
  • Kingdom Animalia: Multicellular, aerobic heterotrophs, derived from zygotes, reproduce sexually and asexually
• Six-kingdom classification system


  Separates the Kingdom Monera into Archaebacteria and Eubacteria based on differences in ribosomal RNA and cell structure
• Three-domain classification system


  • Domain Bacteria: Eubacteria
  • Domain Archaea: Unicellular prokaryotes that thrive in extreme habitats
  • Domain Eukarya: Eukaryotic cells with true nucleus and organelles
• Systematics is the modern classification that studies the evolutionary or phylogenetic relationships between organisms
• Cladogram


  Diagram that depicts patterns of shared characteristics and evolutionary history
• Clade


  A group of species that includes an ancestral species and its descendants
• Monophyletic


  Grouping of the ancestral species and ALL the descendants
• Paraphyletic


  Grouping that consists of the ancestor and SOME (not all) of the ancestor's descendants
• Polyphyletic


  Grouping of several species that LACK a common ancestor
• Carolus Linneaus


  Swedish botanist and natural historian who simplified the classic scientific classification and created the binomial system of nomenclature
• The binomial system allows biology to become an international language as organisms can be universally identified by their scientific name
• The binomial system also eliminates repeated study done on the same organism
• Taxonomy


  The branch of biology dealing with the identification, naming and classifying of organisms
• Taxonomy


  • Ordering organisms into groups called taxa based on affinity or relationship between them
  • Narrowest category is species, broadest is kingdom
• Species


  A group of similar organisms that can interbreed in their own natural environment and are reproductively isolated from other organisms
• The importance of taxonomy includes easier retrieval of information, predicting characteristics of new-found species, and explaining evolutionary relationships
• Five kingdom classification system

  Monera, Protista, Fungi, Plantae, Animalia
• Kingdom Monera


  • Consists of all prokaryotic organisms, including eubacteria, cyanobacteria and archaebacteria
  • All monerans are unicellular, lack true nuclei and lack membrane-enclosed organelles
  • Reproduction occurs mainly by binary fission
• Kingdom Protista


  • All protists are simple eukaryotes with a true membrane-enclosed nucleus and organelles
  • Most are unicellular, but some are organized into colonies
  • Live in fresh water, seawater, and soil
  • Resemble fungi, plants and animals
• Kingdom Fungi


  • Mostly multicellular and unicellular organisms
  • Heterotrophs that obtain nutrients by absorption of organic matter
  • Form spores but do not form seeds
  • Some cause diseases, others are economically and ecologically important
• Kingdom Plantae


  • Most plants live on land unlike their algal ancestors
  • Contain chlorophyll in organelles called chloroplasts
  • Divided into seedless vascular plants and seed bearing vascular plants (gymnosperms and angiosperms)
• Kingdom Animalia


  • Multicellular, aerobic heterotrophs that ingest or parasitize other organisms
  • Nearly all have tissues, organs, and organ systems and are motile during at least part of their life cycle
  • Reproduce sexually and asexually
• Six kingdom classification system

  Separates the Kingdom Monera into archaebacteria and eubacteria