Taxonomy - the branch of biology that deals with the classification and naming of living things.

Levels of Classification

Category         Human           Housefly
Kingdom        Animalia            Animalia
    Phylum            Chordata           Arthropoda
        Class                Mammalia         Insecta
            Order               Primates            Diptera
                Family               Hominidae         Muscidae
                    Genus              Homo                  Musca
                        species             Homo sapiens       Musca domestica

Binomial nomenclature - a two name system for identifying organisms.

Carl Linnaeus (1707-1778)- Swedish botanist, founder of modern taxonomy.
    First to use binomial nomenclature
    Used a Two Kingdom System: Plants and Animals
        Problem - Many organisms did not fit neatly into these groups.
            ex.  mushroom - grows from the soil  and doesn't move, but it can   grow in the dark.

Species - a group of similar organisms that interbreed in nature producing fertile offspring.

Kinds of information used to classify:

Structural
Biochemical
Cytological
Embryological
Behavioral
Fossil

Characteristics of the Five Kingdoms

Unicellular - consisting on one cell.
Multicellular - consisting of numerous cells.
Prokaryotic - having simple cells (without nuclei and without membrane-bound organelles)
Eukaryotic - having complex cells (with nuclei and with membrane-bound organelles)
Autotrophic - capable of making food (organic molecules) from inorganic molecules.  Photosynthesis.
Heterotrophic - capable of taking in food from the environment. (Eating or Absorbing)
 
Monera Protista Fungi Plant Animal
Cell number unicellular uni. and multi. uni. and multi. multicellular multicellular
Cell type prokaryotic eukaryotic eukaryotic eukaryotic eukaryotic
Mode of nutrition auto. and hetero. auto. and hetero. heterotrophic autotrophic heterotrophic

Taxomonic key of the five kingdoms: (Taxonomic keys are also called dichotomous keys)

1.a.  They consists of prokaryotic cells.-------------------------------Kingdom Monera
   b.  They consists of eukaryotic cells.--------------------------------Step 2

2. a.  They are only heterotrophic.------------------------------------Step 3
    b.  At least some members are autotrophic-------------------------Step 4

3. a.  All members are multicellular-----------------------------------Kingdom Animalia
    b.  Some members are unicellular----------------------------------Kingdom Fungi

4. a.  All members are autotrophic and multicellular-------------------Kingdom Plantae
    b.  Some members are autotrophic and unicellular -----------------Kingdom Protista

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