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Taxonomy. The science of classifying organisms . Classify To arrange according to similarities or differences. Why classify?. Biologists use classification to organize living things into groups so that the organisms are easier to study. We classify to make our lives easier.
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Taxonomy The science of classifying organisms. Classify To arrange according to similarities or differences.
Why classify? Biologists use classification to organize living things into groups so that the organisms are easier to study. We classify to make our lives easier.
Aristotle • Plant or animal? • If an animal, does it • Fly • Swim • Walk/Crawl • Simple classifications • Used common names
DISCUSSION QUESTION - Using Aristotle's 3-group system (based on movement), name 2 animals that would fit each of the 3 groups.
Problems with this system? Some animals can walk, swim, and fly
What technology helped scientist improve the classification system? Microscope -1600s
Carolus Linnaeus 1700s • Described organisms with two word names, instead of polynomials • Developed binomial nomenclature • First word = Genus name (Capitalized) • Second word = species name (lowercase) scientific name • Example Canis lupus Always italicized or underlined
Why binomial nomenclature? • Binomial - 2 name • Nomenclature – naming system • Much easier than a 10+ word name under old “polynomial system” • Same name no matter where you go (Latin) • Less confusion
Taxonomic Hierarchy • Names organisms and their relationships from very broad to very specific
Milky waySolar SystemEarthU.S.OhioWestervilleMainsail Dr.283
Three Domains of Life There used to be 2, why do you think there are 3 now?
Domain Archaeabacteria: Life's Extremists...! Archaea are found in the harshest environments on Earth, and are the oldest known organisms on Earth, appearing in the fossil record over 3.6 BILLION years ago (3,600,000,000 years ago!)
Domain Bacteria (or Eubacteria): is familiar to most people when associated with human or animal disease. However, most bacterial species do not (and cannot) cause disease. Most species even play beneficial roles for humans by producing antibiotics and food.
Domain Eukarya A single-celled or multicellular organism whose cells contain a distinct membrane-bound nucleus. (Organism’s cell has a nucleus.)
Why has taxonomy changed throughout history? Do you think it will continue to change?
Prokaryotes • We are now filling out our charts
Archaea • Unicellular prokaryotes • Autotrophs • Cell wall
Eukaryotes Eu = true Have membrane bound nuclei