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• Systematics


  Study of biological diversity and the relationship among organisms
• Taxonomy


  Science of describing, naming, and classifying species
• Phylogenetics


  Study of evolutionary relationship among species
• Why do scientists classify living organisms?


  • To determine known and unknown species
  • To determine the characteristics of each species
  • To determine relationships between these species
• Aristotle

  • A Greek philosopher that classified all animals
  • "Historia Animalium" or "History of Animals" is the first modern zoological work that attempts to describe all the animals known
  • The first to publish and classify animals
  • Grouped creatures into hierarchy
  • "The Great Chain of Being" or "Scala Naturae"
• Carolous Linnaeus


  • Also known as "Carl Von Linné"
  • A Swedish botanist and explorer
  • Developed the Linnean System or the taxonomic classification system
  • Organized organisms from larger to smaller and more specific categories the "Hierarchical System"
  • Created a scientific naming system or the "Binomial System of Nomenclature"
• Why many organisms may have several common names?


  • Common names vary in the country, depending on their dialect
  • Common names vary in the location or in the country
  • Common names may be misleading
• Binomial nomenclature


  A two-part name (genus and epithet – geographic area or the person who discovered it)
• Rules in writing a scientific name


  • The name should be in Latin
  • The genus of an organism begins with a capital letter; the species designation begins with a lowercase letter
  • The entire scientific name is italicized when typewritten or underlined when handwritten
  • All taxa must have an author when described
• Nomenclature codes


  • International Code of Botanical Nomenclature (ICBN) - algae, fungi, and plants
  • International Code of Zoological Nomenclature (ICZB) - animals
  • International Code of Nomenclature Bacteria (ICNB) - bacteria
  • International Committee on Taxonomy of Viruses (ICTV) - Viruses
• How do scientists classify living organisms?


  • Morphological Traits
  • Developmental Traits
  • Genetic Traits – similarities of human DNA and protein sequences to other animals
• Taxonomy


  The discipline of classifying organisms and assigning each organism a universally accepted name
• Kingdom classification


  • Dear King Philip Came Over For Great Soup
• Salmonella spp.


  Bacterium that can cause a type of food poisoning
• Monera


  • Monerans
  • Bacteria
  • They lack nucleus
  • Prokaryotes
  • Archaebacteria and eubacteria
  • Most abundant organism on earth
  • Outnumber all organisms combined
  • All prokaryotes are bacteria, all bacteria belong to Kingdom Monera
• Prokaryotes


  • Lacks nucleus, have cell membrane but do not have membrane-bound organelles such as chloroplasts and mitochondria
  • Have ribosomes different from ribosomes of eukaryotes
  • Smaller than the smallest eukaryotes
  • MOST prokaryotes are single-celled organisms (unicellular)
• Archae-bacteria


  • Ancient bacteria – group of monerans that live in unusually harsh environments
  • Chemically distinct with monerans in several ways
  • Mostly extremophiles
• 4 types of archae-bacteria


  • Methanophiles or methanogens
  • Thermophiles or thermoacidophiles
  • Halophiles
  • Chemosynthesizers
• Eubacteria


  • Eu – true
  • True bacteria and blue green algae (cyanobacteria)
  • All organisms that are traditionally known
  • Peptidoglycan – made up of sugar complex, polysaccharide
  • Survives almost anywhere
• 3 subgroups of eubacteria


  • Gram positive bacteria
  • Gram negative bacteria
  • Gram staining technique
• Cyanobacteria or blue-green algae


  • Much larger than any other prokaryotes because produce oxygen and provides food for other organisms
  • They perform plant-like photosynthesis that helps them to release oxygen as a by product
  • Grow in long filaments, resembling an algae
  • Prokaryotes without cell nuclei and membrane-covered organelles
  • More similar to monerans, than to algae
• Nitrogen-fixing bacteria (rhizobacteria)


  • Gram-negative bacteria that grows in the root nodules of such plants as soybeans, clover, and alfalfa
  • Fix nitrogen from the atmosphere into a form that the plants and the animals that eat the plants, can use
  • Convert gaseous nitrogen into compounds such as ammonia (NH3) so animals and plants use these compounds to make nitrogen containing compounds such as proteins
  • No other kingdom includes organisms that can fix nitrogen
  • Without it, the diversity of life on Earth could not exist
• Protista

  • Plant-like, animal-like, and fungus-like organisms
  • Mostly aquatic
  • Not classified as animals, plants, or fungi
  • Freshwater, marine, and terrestrial habitats
• 3 classification of protists


  • Animal-like protists (protozoans)
  • Plant-like protists (algae)
  • Fungus-like protists
• Animal-like protists (protozoans)


  • 3 types: sarcodinians, zooflagellates, ciliaphorans
• Plant-like protists (algae)


  • Unicellular algae and multicellular algae
• 3 phyla of multicellular algae


  • Green algae (Chlorophyta)
  • Red algae (Rhodophyta)
  • Brown algae (Phaeophyta)
• Fungus-like protists


  • 2 types: slime molds and water molds
• Useful products from seaweed


  • Carrageenan and agar are extracted from red algae
  • Algin is extracted from brown algae that is used as a food additive
• Fungi


  • Breaks down organic materials
  • Provides drugs and aids in food production
  • Causes animal and plant diseases
  • Contribute to the food we eat and to medicine, and to the recycling process
• Symbiotic relationships of fungi

  • Saprophytes
  • Parasites
  • Predators
• Hyphae


  • Tiny tubes filled with cytoplasm and nuclei or nucleus
  • Living growing parts of a multicellular fungi
  • Divided in segments separated by walls which we call the septa
• Multicellular fungi


  • Consists of a mass of hyphae
• Mycelium


  Mass of tangled interwoven hyphae that forms the body of a fungus
• Classification of fungi


  • Zygomycota (common molds)
  • Basidiomycota (club fungi)
• Nucleus


  Living growing parts of a multicellular fungi
• Septa


  Cross walls that divide the hyphae into sections
• Septate hyphae


  Hyphae with cross walls
• Coenocytic hyphae


  Hyphae without cross walls
• Multicellular fungi


  • Consists of a mass of hyphae