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Classification of Organisms
Here are some things that scientists classify or organize:
• The human body
The elements
Interactions in Ecosystems
Scientists also Classify Living Organisms
How could you classify these living things?
Quick, organize these living things into groups:
Did you do it like this?
Or this?
Are there any other ways to group these living things?
Why Classify?
Classification makes it easier to answer questions about living things such as
• How many known species are there?
• What are the defining characteristics of each species?
• What are the relationships between these species?
Classification History
• Aristotle – (4th century B.C./Greek) the first person to organize things scientifically.
• Linnaeus – (18th century/Swedish) Carolus Linnaeus is the father of taxonomy. He grouped things according to their shared characteristics like shape and structure.
• Science is dynamic (changing). As we make new discoveries, our groupings of organisms sometimes change.
Taxonomy• The science of describing, classifying,
and naming living things
Levels of Classification• Kingdom (largest, most general)
• Phylum • Class • Order • Family • Genus • Species (only one kind of organism)
King
Phillip
Came
Over
For
Great
Spaghetti
Binomial Nomenclature (two names)
• What is a puma vs. a mountain
lion vs. a cougar? • Common name: can vary in different
areas• Scientific names are in Latin or Greek
so that all scientists use the same name• Linnaeus simplified the naming process with two
parts; genus and species.• Genus is always capitalized, species is lower case• You can abbreviate the genus, but not the species• Genus and species are in italics or underlined
Felis concolor
What is in a name?
To make your fake scientific name:
•Sara Jones
•Jones Sara
•Jones sara
•Latinize your name
Latin endings
•ae
•us
•ius
•um
•iumJonesium sarius
Genus name Species name
Real Scientific Names
• Felis domesticus
• Tyrannosaurus rex
• Canis familiaris
• Homo sapien
• Panthera onca
• house cat
• T. rex
• dog
• human
• jaugar
Important TermsProkaryote – having no nucleusEukaryote – having a nucleus
Unicellular – made up of one single cellMulticellular – made up of more than one cell
Autotroph – producersHeterotroph – consumers
Sexual Reproduction - 2 parent cellsAsexual Reproduction —1 parent cell
ClassificationDomains
• There are three Domains of living organisms based on their characteristics:
– Archaea (also called Archaebacteria)
– Eubacteria (also called Bacteria)
– Eukaryota (also called Eukarya)
Archaea
EubacteriaEukaryota
Domain Archaea
“Archaea” means “ancient” bacteria.
Organisms in Archaea are:• Unicellular• Prokaryotic• Autotrophic or heterotrophic• Reproduce asexually
Aerial view of hot spring at Yellowstone
Domain Archaea
• Bacteria that have adapted to extreme environments. • Some can survive in extremely hot environments, like
around hot springs and geysers. They are called thermophiles.
• Some can survive in extremely salty environments, like The Great Salt Lake in Utah. They are called halophiles.
• The Domain Archaea has one Kingdom, also called Archaea.
This hot spring is flowing into the Firehole River in Yellowstone. The colors are caused by different varieties of archaebacteria and other microscopic life forms. Scientists can distinguish temperatures of water by the colors present.
Domain Eubacteria“Eu” means “true” bacteria. They
are:• Unicellular• Prokaryotic• Autotrophic or heterotrophic• reproduce asexually• most abundant organisms on
earth. One bacterium can give rise to 10 million in 24 hours.
• Found in almost every habitat on earth.
The Domain Eubacteria has one Kingdom, also called Eubacteria.
Many are common infectious agents.
This is a picture of bacteria on the skin. Bacteria can be shaped like a sphere (cocci) like this picture, like a rod, or like a spiral. The structure in
the middle of this picture is a hair follicle with a hair growing out of it.
Domain Eukaryota (Eukarya)• Eukaryotic• Very diverse• Unicellular or multicellular• Autotrophic or heterotrophic• Reproduce sexually or asexually• Can be split into 4 Kingdoms-
– Protista– Fungi– Plantae– Animalia
DOMAINS
KINGDOMS
The 4 Kingdoms in EukaryotaProtistaMostly unicellular and microscopicAutotrophic or heterotrophic Can be infectious agents
Examples:•Amoeba•Algae•Daphnia•Plasmodium (causes malaria)
PlantaeMulticellular green plantsAutotrophic through photosynthesisHave a cell wall
Examples:•Mosses•Ferns•Trees•Flowering Plants
FungiMulticellularHeterotrophicDecomposersCan be infectious agents
Examples:•Mushrooms•Athlete’s foot•Bread Mold
AnimaliaMulticellular AnimalsHeterotrophicNo Cell Wall
Examples:•Insects •Spiders•Crabs•Birds•Humans
Dichotomous Key
• A guide to identifying organisms
• It is based on statements/questions that will be answered with one of two responses. These responses lead you to other statements until you reach the identity of the organism.
I’m Talkin Bout (poems)
On other side you should see:
Archaebacteria Eubacteria Protista
Fungi Plantae Animalia
I’m talkin bout protista
I’m talkin bout single
celled, food makin,
eukaryotic
I’m talkin bout algae
I’m talkin bout protista
I’m talkin bout FungiI’m talkin bout spore producing, eating old bread, eukaryotic
I’m talkin bout moldI’m talkin bout Fungi
Protista
I’m Talkin Bout (poems)I’m talkin bout name of kingdomI’m talkin bout 3 descriptions of kingdomI’m talkin bout one exampleI’m talkin bout name of kingdom
Example:I’m talkin bout ArchaebacteriaI’m talkin bout heat lovers, salt lovers, extremophilesI’m talkin bout blue-green bacteriaI’m talkin bout Archaebacteria
Arch Eubac Prot