BIO - classification

• Mammals are endothermic vertebrates with hair or fur, four limbs, and produce milk to feed their young instead of laying eggs.
• Taxonomy is the science of classification
• It is used to study the diversity of life
• Organisms are grouped according to shared lines of evolutionary descent
• Organisms are given scientific names because common names are misleading
• Organisms are classified to reduce confusion and help with classification
• Scientific names are given using Binomial Nomenclature by Linnaeus
• The first part of the name is the Genus and is capitalized
• The second part of the name is the Species and is lowercase
• Scientific names are underlined when written by hand and italicized when typed
• Viruses are not classified the same way as organisms because they are not living
• Viruses have characteristics such as no cell type, no cell wall, non-cellular body type, no way to produce energy for itself, and replication requiring a host cell
• Viruses go through Lytic and Lysogenic cycles of reproduction
• Kingdom, Phylum, Class, Order, Family, Genus, Species - Linnaeus's system is hierarchical
• The most general level is Kingdom and the most specific is Species
• Domain classification includes Archaea, Bacteria, and Eukarya
• Dichotomous keys are tools for identifying unknown organisms using observable characteristics
• Steps include beginning at the top, answering paired questions with yes or no, and following directions based on answers
• Domain Archaea:

  • Cell Type: Prokaryotic
  • Cell Wall: No peptidoglycan
  • Number of Cells: Unicellular
  • Nutrition: Auto- or Heterotroph
  • Reproduction: Asexual
  • Examples: Methanogens, Halophiles, Thermophiles
  • Live in Extreme Habitats
  • Bacillus infernus lives in deep sea vents in the ocean and obtains energy from Earth’s heat
• Domain Bacteria:

  • Cell Type: Prokaryotic
  • Cell Wall: Peptidoglycan
  • Number of Cells: Unicellular
  • Nutrition: Auto- or Heterotroph
  • Reproduction: Asexual
  • Examples: E. coli, Streptococcus
  • Bacteria contain flagella that enable bacterial cells to move
• Domain Eukarya:

  • Classification of Protists:
  • Cell Type: Eukaryote
  • Cell Wall: Cellulose (some)
  • Number of Cells: Unicellular or Multicellular
  • Nutrition: Auto- or Heterotroph
  • Reproduction: Sexual or Asexual
  • Examples: Paramecium, Euglena, Algae, Amoeba
  • Heterotrophic, Autotrophic, Decomposers
• Kingdom Fungi:

  • Cell Type: Eukaryote
  • Cell Wall: Chitin
  • Number of Cells: Unicellular or Multicellular
  • Nutrition: Heterotroph
  • Reproduction: Mainly Asexually
  • Examples: Yeast, Morel, Bread Mold, Mushroom
  • Some fungi are edible and used in producing antibiotics, cheeses, bread, beer, wine, soy sauce, and tofu
  • Fungi are decomposers, recycling organic matter
  • Symbiotic relationships: Lichen (Fungus + Algae) and Mycorrhizae (Fungus + Plant roots)
• Kingdom Plantae:

  • Cell Type: Eukaryote
  • Cell Wall: Cellulose
  • Number of Cells: Multicellular
  • Nutrition: Autotroph
  • Reproduction: Sexual or Asexual
  • Examples: Fruiting plants, flowers, trees, grasses
  • Classified based on water conducting tissue, seeds, and flowers
• Classification of Animals:

  • Cell Type: Eukaryote
  • Cell Wall: No cell wall
  • Number of Cells: Multicellular
  • Nutrition: Heterotroph
  • Movement: Mobile
  • Reproduction: Sexual
  • Examples: Invertebrates (bugs and worms), vertebrates (humans, monkeys, dogs)
• Kingdom Archaea Bacteria:

  • Cell type: Prokaryotic
  • Cell structure: No peptidoglycan in cell wall
  • Number of cells: Single-celled
  • Nutrition: Autotrophs or heterotrophs
  • Reproduction: Asexual
  • Examples: Methanogens, Halophiles, Thermophiles
  • Live in extreme habitats
• Domain Bacteria, Kingdom Eubacteria:

  • Cell type: Prokaryotic
  • Cell structure: Peptidoglycan in cell wall
  • Number of cells: Single-celled
  • Nutrition: Autotrophs or heterotrophs
  • Reproduction: Asexual
  • Examples: Streptococcus, E. coli
• Bacteria helpful and harmful organisms:

  • Helpful: Make food (cheese, yogurt), clean up oil spills, aid in human digestion, carry out photosynthesis, decomposers, fix nitrogen
  • Harmful: Cause diseases (pathogens) like dental plaque, strep throat, pneumonia, diphtheria, acne
  • Prevention: Slow growth with cold temperatures, kill with heat, chemicals (bleach, disinfectants, alcohol), antibiotics
• Kingdom Protista is the first kingdom of eukaryotic organisms
• Cell type: eukaryotes have a nucleus and membrane-bound organelles like mitochondria and chloroplasts
• Cell wall: if present, it usually contains cellulose
• Number of cells: can be single-celled or multi-celled
• Can be autotrophs or heterotrophs
• Can be mobile or motile
• Can be sexual or asexual
• Examples: Paramecium, Euglena, algae, and amoebas
• Considered the "junk drawer" of organisms as they have diverse characteristics that don't fit neatly into other kingdoms
• Protists can be classified based on their mode of nutrition
• Animal-like: heterotrophic, can be further classified by movement
• Plant-like: autotrophic, can make their own food from the Sun, e.g., Euglena
• Fungus-like: decomposers, reproduce by forming spores, e.g., water mold and slime molds