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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