Chapter 17 Notes,
Taxonomy
THE USEFULNESS OF ORGANIZATION
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Have you ever heard your parents tell you to
clean your room?
Why do you suppose they told you to clean
your room?
If you went to the school's library to look for
a book, where would you begin?
Are all the books in the library randomly
arranged without any rhyme or reason?
Or is there a system of arrangement that
allows you to find what you are looking for in
the quickest way possible?
WOULD YOU RATHER TRY TO FIND
SOMETHING HERE?
OR HERE?
WHY DO BIOLOGISTS ORGANIZE LIVING
ORGANISMS?
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Biologists have named about 1.7 million
species on our planet.
There are about than 62,000 (known)
vertebrate species on our planet.
There are about than 1,300,000 (known)
invertebrates.
There are about than 320,000 (known)
species of plants on our planet.
About 13,000 new species are added per year.
Not to mention all the species of bacteria,
fungus, and protozoa that are found all over
our entire planet.
WHAT IS TAXONOMY
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Taxonomy is the field of biology that explains
how biologists organize, identify, name, and
classify living organisms.
In taxonomy, organisms are grouped into
various groups called taxons.
Taxons are classified by similarities and
differences between organisms.
The first and broadest taxon in taxonomy is
called a domain.
Domains are classified by cell type and cell
structure.
WHAT ARE THE THREE DOMAINS IN
BIOLOGY?
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Domain Bacteria – organisms that are
prokaryotic, unicellular, and they have cell
walls made of peptidoglycan.
Bacteria can be aerobic or anaerobic.
Bacteria are the most abundant living
organisms on the planet. There are probably
more bacteria in your own body than there
are people in the world.
DOMAIN BACTERIA (ESCHERICHIA COLI)
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E. coli is one of the most common forms of
bacteria found in the intestinal tract of
warm-blooded animals (including humans).
Most strains of E. coli are harmless, but
some strains can cause severe food
poisoning.
THREE DOMAINS IN BIOLOGY
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Domain Archaea – These bacteria used to be
classified together with Domain Bacteria.
Cell walls do not contain peptidoglycan.
Unicellular like bacteria.
Also called extremophiles, because they can
live in extreme hostile environments.
Examples of environments inhabited by
bacteria in domain Archaea are hot springs,
hypersaline lakes, extreme depths and
pressures and temperatures etc.
DOMAIN ARCHAEA (EXTREMOPHILES)
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These are examples of hostile environments
occupied by extremophiles.
Hot springs in Yellowstone National Park and
hydrothermal vents giving off hydrogen sulfide.
THREE DOMAINS IN BIOLOGY
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Domain Eukarya – This domain includes all
of the living organisms that have cells with a
membrane-bound nucleus and membranebound organelles.
There are four smaller taxons called
Kingdoms found in the domain Eukarya.
These kingdoms are Kingdom Protista,
Fungi, Plantae, and Animalia.
KINGDOMS IN EUKARYA
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Kingdom Protista – Protists can be unicellular,
multicellular, or colonial.
Protists can be autotrophic or heterotrophic.
Protists have no organs or tissues.
There are plant-like protists like algae and kelp.
There are animal-like protists like amoebas and
paramecium.
There are fungus-like protists like slime-molds
and mildews.
Euglena are protists with both plant-like and
animal-like characteristics.
KINGDOM PROTISTA
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Protists are kind of like the oddball misfits of Eukarya that
don't fit into any other kingdoms.
PLANT-LIKE PROTISTS
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Kelp and algae look like plants, but they are actually
considered protists because they lack the complex
tissues and organs that are found in plants.
ANIMAL-LIKE PROTISTS (PROTOZOA)
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Paramecium with cilia for locomotion .
FUNGUS-LIKE PROTISTS
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Slime mold and mildew thrive in moist environments.
KINGDOMS IN EUKARYA
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Kingdom Fungi – Organisms in this kingdom
are both unicellular and multicellular.
Fungi are heterotrophic, lack the ability to
move, and have cell walls made of Chitin.
Some fungi are parasitic. They grow and feed
on other organisms.
Some fungi are saprobes that eat dead or
decaying organic matter.
Fungi secrete digestive enzymes externally
and absorb digested materials.
KINGDOM FUNGI
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Probably the most common and well known of
all the fungi is the mushroom.
KINGDOMS IN EUKARYA
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Kingdom Plantae – All organisms in Kingdom
Plantae are multicellular.
All plants have cell walls made up of cellulose.
Most plants are autotrophic and they possess
chloroplasts.
All plants possess cells that are organized into
tissues, and most plants possess organs such
as roots, stems, and leaves.
Plants lack the ability to move, with the
exception of some reproductive cells that bear
flagella that propel them through water.
KINGDOM PLANTAE
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Plants are the first organism we have discussed
that have complex tissues and organs.
KINGDOMS IN EUKARYA
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Kingdom Animalia – Animals are heterotrophic,
multicellular, and they do not have cell walls.
Remember animal cells have a cell membrane.
Most animal cells are organized into tissues ,
tissues are organized into organs, and organs
are organized into organ systems.
Most animals have the ability to move and some
type of a nervous system (brain).
KINGDOM ANIMALIA
TAXONOMIC HEIRARCHY
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This is a simple acrostic or mnemonic to help
remember the taxonomic hierarchy.
King – Kingdom
Peter – Phylum (Division for plants and bacteria)
Came – Class
Over – Order
From – Family
Germany – Genus
Swimming - Species
TAXONOMIC HIERARCHY
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Using the example of the brown and black bear.
Both are in the Kingdom Animalia because they
are animals and not plants, fungi, bacteria etc.
Both are in Phylum Chordata because they both
have a vertebral column with a spinal cord.
Both are in the Class Mammalia because they
both have hair, mammary glands etc.
Both are in the Order Carnivora because they
consume meat and have carnivorous teeth.
Both are in the Family Ursidae which includes all
the bears found all over the world.
Taxonomic Hierarchy (Black Bear)
Taxonomic Hierarchy (Brown Bear)
TAXONOMIC HIERARCHY
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Both bears are in the Genus Ursus which also
includes the Polar Bear (Ursus maritimus) and
the Asiatic Black Bear (Ursus thibetanus).
All of these bears are very closely related.
The bears below are more distantly related to
other bears in the family Ursidae so they are
all in their own separate genera.
The Giant Panda Bear (genus Ailuropoda)
The Sun Bear (genus Helarctos)
The Sloth bear (genus Melursus)
The Spectacled bear (genus Tremarctos)
Genus Ursus
Other Bears in Family Ursidae but not in Genus Ursus
HERE IS A COMPARISON WITH THE
FELIDAE (CAT) FAMILY
TAXONOMIC HIERARCHY
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The last and most specific taxon is the species
name or species epithet.
Species refers to only one specific group of
organisms that are a successfully reproducing
population of organisms.
Each species may have different common
names, depending on the location, but it will
always have only one species name.
For example, Felis concolor has many different
common names like the cougar, mountain lion,
puma, mountain cat, catamount, or panther.
FELIS CONCOLOR
BINOMIAL NOMENCLATURE
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Species names are universal, so no matter
where you travel around the world, the species
name is always the same.
Species names are also similar to our names.
People have a first name and a last name.
Your first name is more general (John, Sarah,
Thomas etc.). Your last name is more specific
(Johnson, Smith etc.).
But when someone calls you by both your first
name and last name it is more specific.
BINOMIAL NOMENCLATURE
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The first part of the species name is the Genus
name. This name indicates which animals it is
most closely related to.
The second part of the name is the specific
species epithet.
For example Ursus americanus is scientific
species name of the Black bear.
Or Ursus arctos is the name for the Brown bear.
Species can also have a third name, which is
called a subspecies name. Like Ursus arctos
horribilis the Grizzly bear, or Ursus arctos
middendorfi the Brown bear.
IS THIS AN ELK OR MOOSE?
RULES OF BINOMIAL NOMENCLATURE
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When using proper binomial nomenclature, the Genus
should be always be capitalized , and the species name,
or specific species epithet should always be lowercase.
When typed, the species name should be italicized.
When writing species names by hand , the species name
should always be underlined.
If a species name is repeated when writing a paper or a
scientific report, the genus may be abbreviated (F.
concolor) after the first time it has been written .