18

1
Section Outline
Section 18-1

• 181 Finding Order in Diversity
• A. Why Classify?
• B. Assigning Scientific Names
• 1. Early Efforts at Naming Organisms
• 2. Binomial Nomenclature
• C. Linnaeuss System of Classification

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2
Flowchart
Section 18-1
Linnaeuss System of Classification
Kingdom
Phylum
Class
Order
Family
Genus
Species
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3
Figure 18-5 Classification of Ursus arctos
Section 18-1
Coral snake
Abert squirrel
Sea star
Grizzly bear
Black bear
Giant panda
Red fox
KINGDOM Animalia
PHYLUM Chordata
CLASS Mammalia
ORDER Carnivora
FAMILY Ursidae
GENUS Ursus
SPECIES Ursus arctos
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4
One Big Family?
Interest Grabber
Section 18-2

• How can you determine if one organism is closely
  related to another? It may seem easy, but it
  isnt, and looks are often deceiving. For
  example, roses and orchids are both flowering
  plants, but roses grow on bushes or vines and
  have thorns. Many orchids dont even grow in
  soilthey can grow in trees! Rose and orchid
  blossoms look very different, and roses and
  orchids cannot produce hybrids, or offspring of
  crosses between parents with different traits.

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5
Interest Grabber continued
Section 18-2

• 1. Do you think roses and orchids are closely
  related? Explain your answer.
• 2. Now, apply the same logic to dogs. Different
  breeds of dogssuch as a Labrador retriever and a
  colliecan breed and produce offspring. So what
  is the difference between the rose-orchid
  combination and the Lab-collie combination?
• 3. What defines a species? Is appearance
  important? What other factors might be considered?

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6
Section Outline
Section 18-2

• 182 Modern Evolutionary Classification
• A. Problems With Traditional Classification
• B. Evolutionary Classification
• C. Classification Using Cladograms
• D. Similarities in DNA and RNA
• E. Molecular Clocks

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7
Traditional Classification Versus Cladogram
Section 18-2
Appendages
Conical Shells
Crustaceans
Gastropod
Crab
Crab
Limpet
Limpet
Barnacle
Barnacle
Molted exoskeleton
Segmentation
Tiny free-swimming larva
TRADITIONAL CLASSIFICATION
CLADOGRAM
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8
Traditional Classification Versus Cladogram
Section 18-2
Appendages
Conical Shells
Crustaceans
Gastropod
Crab
Crab
Limpet
Limpet
Barnacle
Barnacle
Molted exoskeleton
Segmentation
Tiny free-swimming larva
TRADITIONAL CLASSIFICATION
CLADOGRAM
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9
Section Outline
Section 18-3

• 183 Kingdoms and Domains
• A. The Tree of Life Evolves
• B. The Three-Domain System
• C. Domain Bacteria
• D. Domain Archaea
• E. Domain Eukarya
• 1. Protista
• 2. Fungi
• 3. Plantae
• 4. Animalia

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10
Concept Map
Section 18-3
Living Things
are characterized by
Important characteristics
which place them in
and differing
Domain Eukarya
Cell wall structures
such as
which is subdivided into
which place them in
which coincides with
which coincides with
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11
Figure 18-12 Key Characteristics of Kingdoms and
Domains
Section 18-3
Classification of Living Things
DOMAIN KINGDOM CELL TYPE CELL
STRUCTURES NUMBER OF CELLS MODE OF
NUTRITION EXAMPLES
Bacteria Eubacteria Prokaryote Cell walls with
peptidoglycan Unicellular Autotroph or
heterotroph Streptococcus, Escherichia coli
Archaea Archaebacteria Prokaryote Cell walls
without peptidoglycan Unicellular Autotroph
or heterotroph Methanogens, halophiles
Protista Eukaryote Cell walls of cellulose in
some some have chloroplasts Most unicellular
some colonial some multicellular Autotroph or
heterotroph Amoeba, Paramecium, slime molds,
giant kelp
Fungi Eukaryote Cell walls of
chitin Most multicellular some
unicellular Heterotroph Mushrooms, yeasts
Plantae Eukaryote Cell walls of cellulose
chloroplasts Multicellular Autotroph Mos
ses, ferns, flowering plants
Animalia Eukaryote No cell walls or
chloroplasts Multicellular Heterotroph
Sponges, worms, insects, fishes, mammals
Eukarya
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12
Figure 18-13 Cladogram of Six Kingdoms and Three
Domains
Section 18-3
DOMAIN ARCHAEA
DOMAIN EUKARYA
Kingdoms
Eubacteria Archaebacteria Protista Plantae Fungi A
nimalia
DOMAIN BACTERIA
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