BIO 11 Diversity of Living Things p.326 Biology 11
Taxonomy • Taxonomy: science of classifying organisms • Why bother classifying? • To identify organisms • To show how organisms are related
Once upon a time…. • Aristotle’s classification system: Plant or Animal • p. 327 “Try This Activity”
There were some organisms that didn’t seem to fit in either of Aristotle’s categories
Now what? • The invention of the microscope in the 17th century further complicated things. • Microrganisms i.e. bacteria neither plants nor animals • Classification system needed to be improved…
p.329 Biology 11 • Currently, all organisms are divided into 6 kingdoms • Using p.329-330, list the 6 kingdoms and give 2 examples of each
The 6 Kingdoms • Eubacteria i.e. bacteria, cyanobacteria • Archaebacteria i.e. methanogens, extreme halophiles • Protista i.e. algae, protozoa • Fungi i.e. mushrooms, yeasts • Plantae i.e. ferns, flowering plants • Animalia i.e. mammals, spiders
In the Eukaryota domain, kingdom Protista has the most biological diversity • Biological diversity: variety of living organisms
Levels of Classification • 7 taxa / levels: • Kingdom is the largest taxon and most vast and non-specific • Species is the smallest and most specific taxon • How to remember?
Taxonomic Systems • Carl Linnaeus pioneered current classification system. • More physical and structural features organisms have in common, the more closely related they are • Linnaeus invented binomial nomenclature
Binomial Nomenclature • 2-word scientific naming system that names organisms using format “Genus species”. • Uses Latin words • Genus is capitalized, species is not i.e. Castor canadensis = beaver Felix domesticus = pet cat
Genus: Biological group of species that are closely related • Species: Group of organisms that can reproduce among themselves and produce fertile offspring • i.e. ligers (from cross of lion + tiger) males are sterile; lions and tigers are different species • i.e. mules (from donkey + horse) are sterile; donkeys and horses are different species
Benefits of Binomial Naming System • Why is it useful for people around the world to use the same name for organisms? • Compare the names of: • Grizzly bear = Ursus horribilis • Polar bear = Ursus maritimus • What does it mean that these organisms belong to the same genus?
Assignment • p.334 # 2, 5 • Namus gamus Assignment – due ?
Prokaryote vs Eukaryote • Prokaryote: an organism who does not have a nuclear membrane • Fewer organelles than eukaryotes • Kingdoms: (eu)bacteria, archaebacteria • Eukaryote: an organism who has a nuclear membrane • Kingdoms: protists, fungi, plants, animals