Classification of Organisms

The Necessity of ClassifyingPeople group things together for convenience…

For example…Musical instruments are grouped together…

However, in any classification system there are problems…

For instance, a piano has strings…yet it is not stroked like a violin…so should it be in the same group?

The Necessity of Classifying

The same problems apply to taxonomy (the science of classifying organisms into groups)…

There are millions of different kinds of organisms…

The Modern Classification System

• Kingdom• Phylum• Class• Order• Family• Genus

• Species

Rules for Biological Classification

1. Each group on one level of the hierarchy may be divided into several groups on the next lower level.

2. Each group in the hierarchy has various characteristics that all of the levels under the group posses.

3. Each level of the hierarchy can be divided into smaller groups before reaching the next lower level.

Terms to Know

• Eukaryotic – Membrane bound organelles• Prokaryotic – Non-Membrane bound organelles• Heterotrophic – Cannot produce own food• Autotrophic – Produces own food• Unicellular – A single cell organism• Colonial – Group of similar cells living together

(but the cells are unicellular)• Multicellular – Consists of many cells

The Kingdoms

There are Five Kingdoms:

AnimaliaMonera } Archaebacteria and Eubacteria

ProtistaFungi

Plantae

Kingdom Monera

• Prokaryotic -Lack membrane-bound organelles

• Microscopic • Unicellular or colonial• Example: Bacteria

Kingdom Monera - Archaebacteria

• Archaebacteria are found in extreme environments such as hot boiling water and thermal vents under conditions with no oxygen

or highly acid environments.

• Finding Archaebacteria: The hot springs of Yellowstone National Park, USA, were among the first places Archaebacteria were discovered. The biologists pictured are immersing microscope slides in the boiling pool onto which some archaebacteria might be captured for study.

Kingdom Monera - Eubacteria• Like archaebacteria,

eubacteria are complex and single celled. 

• Most bacteria are in the EUBACTERIA kingdom.

• They are the kinds found everywhere and are the ones people are most familiar with. 

• This is a picture of E. coli

Kingdom Monera - Eubacteria• Most eubacteria are

helpful.  • Some produce

vitamins and foods like yogurt. 

• However, these eubacteria, Streptococci pictured, can give you strep throat!

Kingdom Fungi

• Eukaryotic – Have membrane bound organelles

• Multicellular• Heterotrophic• Example:

Mushrooms and molds

Kingdom Protista• Eukaryotic – Have

membrane bound oragnelles

• Unicellular• Both autotrophic and

heterotrophic• Example: Algae and

Protozoans• Protists include all

microscopic organisms that are not bacteria, not animals, not plants and not fungi. 

Kingdom Plantae• Eukaryotic – Have

membrane bound organelles.

• Multicellular• Autotrophic• Examples: Plants • Without plants, life on

Earth would not exist!  Plants feed almost all the heterotrophs (organisms that eat other organisms) on Earth.  Wow!

Kingdom Animalia

• Eukaryotic – Have membrane bound organelles

• Multicellular• Heterotrophic• Examples: Dogs and

people

Scientific NamesOrganisms are given a scientific name…

This name uses a system of Binomial Nomeclature…

Bionomial means “two-names”

Nomenclature means “naming”

Scientific names use Latin, because Linnaeus (the founder of the system) spoke Latin.

Genus-Species NamesOrganisms scientific name uses the genus-species

of the organism…

The name is always in italics…

Only the Genus name is capitalized…

Example: Equus caballus - common horse Equus asinus - donkey

Biblical Kind vs SpeciesA “kind” of animal refers to not just species, but similar

types…

For example: Dogs are Canine familiaris but they are the same “kind” of animal as the wolf or coyote.

On the ark, God sent Noah two of every “kind” of animal…Most likely, there was not dogs and wolves and coyotes, but a representative “kind” that has become all the variations we have today.

The End of Classification!