1. Organizing Life’s Diversity
Unit 5
Chapter 17

2. What is classification?
the grouping of objects or information based on similarities
This helps biologists understand how organisms are related to each other.
This is useful in agriculture, forestry, biochemistry, and medicine (to name a few fields).

3. Taxonomists study taxonomy.
the branch of biology that groups and names organisms based on studies of their different characteristics
Click on image to play video.

4. Aristotelian classification
Life
Plant
Animal
Herb Shrub Tree
Aristotle grouped organisms based on appearance and abilities.

5. Carolus Linnaeus: 1707-1778 Swedish botanist
Created modern classification system based on physical and structural similarities
Modern taxonomists have altered the Linnaean system to reflect evolutionary relationships.

6. Binomial nomenclature
two-word naming system to identify organism
Genus: group of related species
always capitalized
Specific epithetic: particular characteristic
always lower case
Ex: Homo sapiens
When writing the scientific name which is Latin, one must italicize when typing or underline when handwriting.
Genus specific epithet

7. Common names
Many people refer to organisms by common names rather than scientific names.
Be careful that common names do not always reflect the biology of the organism.
Scientific name: Fragaria ananassa
Common name: strawberry

8. Dichotomous key: system to identify organisms and their scientific names
A key is made up of sets of numbered statements.
Each set deals with a single characteristic of an organism, such as leaf shape or arrangement.

10. How living things are classified
Taxon: a group of organisms (taxa, pl.)
These groups (taxa) can be very broad or very specific.
The taxonomic levels from most broad to most specific: kingdom, phylum, class, order, family, genus, species

11. Taxonomic levels Domain Eukarya Kingdom Animalia Phylum Chordata Class
Mammalia
Order
Carnivora
Family
Felidae
Genus
Lynx
Species
Lynx
rufus
Lynx
canadensis
Bobcat
Lynx

12. Comparing related animals
Lynx
Bobcat
Lynx rufus, lynx
Panthera concolor, mountain lion
Lynx canadensis, bobcat
Which two are more related? How do you know?
Mountain lion

13. What determines evolutionary relationship?
Anatomy and physiology
Common structures imply a common ancestor.
Breeding and behavior patterns
Geographic distribution
DNA and biochemistry
DNA comparisons between these plants show almost no difference.

14. Phylogeny: Studying the evolutionary histories and relationships of organisms
Cladistics: a phylogenic study that assumes probabl groups of organisms diverged and evolved
Allosaurus
Velociraptor
Archaeopteryx
Sinornis
Theropods
Feathers with
shaft, veins,
and barbs
Flight feathers;
arms as long
as legs
3-toed foot;
wishbone
Down
feathers
Light bones

15. Fan model to indicate phylogeny

16. Modern six-kingdom classification
Archaebacteria: prokaryotic
Eubacteria: prokaryotic
Protists: eukaryotic
Fungi: eukaryotic
Plants: eukaryotic
Animals: eukaryotic

17. Archaebacteria overview
Most live in extreme environments such as swamps, deep-ocean hydrothermal vents, and seawater evaporating ponds.
Most do not use oxygen to respire.

18. Eubacteria overview very strong cell walls
a less complex genetic makeup than found in archaebacteria or eukaryotes
diverse habitat

19. Section 17.2 Summary – pages 450-459
A Paramecium
Protists: A diverse group
Anal
pore
Cilia
Kingdom Protista contains diverse species that share some characteristics.
Oral
groove
A protist is a eukaryote that.
Gullet
Contractile
vacuole
Micronucleus and
macronucleus
Section 17.2 Summary – pages

20. Protist overview lacks complex organ systems
lives in moist environments
diverse metabolism

21. Fungi overview Decomposes matter by absorbing materials
Multicellular or unicellular

22. Plant overview Multicellular Photosynthetic: produce oxygen Immobile
Cell walls

23. Animal overview Multicellular Mostly mobile Lack cell walls
Diverse habitats