chapter 18 classification the diversity of life. why is it necessary to classify? 1.5 million...
TRANSCRIPT
Chapter 18 Classification
The diversity of life
Why is it necessary to classify?• 1.5 million species on the
planet so all creatures must be organized with a universal system. We call this taxonomy.
• Scientists cannot use common names because they change depending on where you live.
For example: cougar, panther, puma, mountain lion all represent the same animal. It has a scientific name – Felis concolor
Scientific Names• Carolus Linneaus – Swedish botanist who
began the modern naming system.• Developed a two word naming system called
binomial nomenclature (latin)
• 2 name naming system • Scientific names are
• Descriptive• In Latin• 2 words – capitalize the first letter of the first
word and lowercase everything else. • First word is Genus second word is species
Ursus maritimus
Examplesscientific name = genus + species
• Homo sapien• Canis familiarius• Felis domesticus• Drosophilia melanogaster
HumanDogCatFruit fly
Classification System• We organize all life on
Earth into 9 levels. Each level is called a taxon.
• Domain is the largest – 3 large groups (see below)
• Species is the smallest
Classification LevelsExample: Grizzly bear
Human Taxonomy Levels
Changing Number of Kingdoms
History of Kingdoms:• 1700’s - 2 kingdoms –Plants and Animals• 1800’s – 3 kingdoms – Plants, Animals, Protists
(pond water critters)• 1950’s – 5 kingdoms – Monera (bacteria),
Protists, Fungi, Plants and Animals• 1990’s – 6 kingdoms - Eubacteria,
Archaebacteria, Protists, Fungi, Plants and Animals.
Section 18-3 Kingdoms and Domains• Shown below are the three domains and the 6 modern
kingdoms we use today.
Domain: Bacteria and Archaea1. Kingdom: Bacteria• unicellular• prokaryotic• cell wall contains a
special molecule called peptidoglycan.
2. Kingdom: Archaebacteria
•Live in extreme environments
•Cell wall lacks peptidoglycan
Domain Eukarya3. Kingdom Protista
• Eukaryotic organisms (most are one celled)• Shows the greatest variety of organisms• Photosynthetic or heterotrophic
Domain Eukarya4. Kingdom Fungi
• Absorptive heterotrophs – absorb nutrients through their bodies
• Feed on dead or decaying organic matter• Many are multicellular• Yeast is unicellular
Domain Eukarya5. Kingdom Plantae
• Multicellular• Autotrophs (do
photosynthesis)• Cellulose in cell wall
Domain Eukarya 6. Kingdom Animalia
• Multicellular• Heterotrophic• Eukaryotic• Invertebrates
and Vertebrates