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The Six Kingdoms
When Linnaeus developed his system of
classification, there were only two
kingdoms,Plants and Animals. But the
use of the microscope led to the
discovery of new organisms and the
identification of differences in cells. A
two-kingdom system was no longer
useful.
Today the system of classification
includes six kingdoms.
The Six Kingdoms:
Plants, Animals, Protists,
Fungi, Archaebacteria,
Eubacteria.
How are organism placed
into their kingdoms?
 Cell type, complex or
simple
 Their ability to make
food
 The number of cells in
their body
Plants
You are probably quite familiar with the
members of this kingdom as it contains
all the plants that you have come to
know - flowering plants, mosses, and
ferns. Plants are allmulticellular and
consist of complex cells.
In addition plants
are autotrophs,organisms
that make their own food.
With over 250,000 species, the plant
kingdom is the second largest
kingdom. Plant species range from
the tiny green mosses to giant trees.
Without plants, life on Earth
would not exist! Plants feed
almost all the heterotrophs
(organisms that eat other
organisms) on Earth. Wow!
Animals
The animal kingdom is the largest
kingdom with over 1 million known
species.
Sumatran Tiger - Kingdom: Animalia,
Phylum, Chordata, Class Mammalia, Order
Carnivora, Family Felidae,
All animals consist of many
complex cells. They are
also heterotrophs.
Members of the animal
kingdom are found in the most
diverse environments in the
world.
Genus Pathera, Species tigris
Archaebacteria
In 1983, scientists tool samples from a
spot deep in the Pacific Ocean where
hot gases and molten rock boiled into
the ocean form the Earth’s interior. To
their surprise they discovered
unicellular (one cell) organisms in the
samples. These organisms are today
classified in the
kingdom, Archaebacteria.
Archaebacteria are found in
extreme environments such
as hot boiling waterand 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 above are immersing
microscope slides in the
boiling pool onto which some
archaebacteria might be
captured for study.
Eubacteria
Like archaebacteria, eubacteria are
complex and single celled. Most
bacteria are in
theEUBACTERIA kingdom. They are
the kinds found everywhere and are the
ones people are most familiar with.
Eubacteria are classified in their own
kingdom because their chemical
makeup is different.
Most eubacteria are
helpful. Some produce vitamins
and foods like yogurt. However,
these eubacteria, Streptococci
pictured above, can give you strep
throat!
Fungi
Mushrooms, mold and mildew are all
examples of organisms in the
kingdom fungi.
Most fungi
are multicellular and consists of many
complex cells.
Fun Facts about Fungi
Some fungi taste great and others can
kill you!
Fungi are organisms that
biologists once confused with
plants, however, unlike
plants, fungi cannot make
their own food. Most obtain
their food from parts of plants
that are decaying in the soil.
Protists
Slime molds and algae are protists.
Sometimes they are called the odds and
ends kingdom because its members are
so different from one
another. Protists include all
microscopic organisms that
are not bacteria, notanimals, not plants
and not fungi.
Most protists are unicellular. You may
be wondering why those protists are not
classified in the Archaebacteria or
Eubacteria kingdoms.
It is because, unlike bacteria, protists are
complex cells.
These delicate looking diatoms are
classified in the protist kingdom.

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The Six Kingdoms

  • 1. The Six Kingdoms When Linnaeus developed his system of classification, there were only two kingdoms,Plants and Animals. But the use of the microscope led to the discovery of new organisms and the identification of differences in cells. A two-kingdom system was no longer useful. Today the system of classification includes six kingdoms. The Six Kingdoms: Plants, Animals, Protists, Fungi, Archaebacteria, Eubacteria. How are organism placed into their kingdoms?  Cell type, complex or simple  Their ability to make food  The number of cells in their body Plants You are probably quite familiar with the members of this kingdom as it contains all the plants that you have come to know - flowering plants, mosses, and ferns. Plants are allmulticellular and consist of complex cells. In addition plants are autotrophs,organisms that make their own food.
  • 2. With over 250,000 species, the plant kingdom is the second largest kingdom. Plant species range from the tiny green mosses to giant trees. Without plants, life on Earth would not exist! Plants feed almost all the heterotrophs (organisms that eat other organisms) on Earth. Wow! Animals The animal kingdom is the largest kingdom with over 1 million known species. Sumatran Tiger - Kingdom: Animalia, Phylum, Chordata, Class Mammalia, Order Carnivora, Family Felidae, All animals consist of many complex cells. They are also heterotrophs. Members of the animal kingdom are found in the most diverse environments in the world.
  • 3. Genus Pathera, Species tigris Archaebacteria In 1983, scientists tool samples from a spot deep in the Pacific Ocean where hot gases and molten rock boiled into the ocean form the Earth’s interior. To their surprise they discovered unicellular (one cell) organisms in the samples. These organisms are today classified in the kingdom, Archaebacteria. Archaebacteria are found in extreme environments such as hot boiling waterand 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 above are immersing microscope slides in the boiling pool onto which some archaebacteria might be captured for study.
  • 4. Eubacteria Like archaebacteria, eubacteria are complex and single celled. Most bacteria are in theEUBACTERIA kingdom. They are the kinds found everywhere and are the ones people are most familiar with. Eubacteria are classified in their own kingdom because their chemical makeup is different. Most eubacteria are helpful. Some produce vitamins and foods like yogurt. However, these eubacteria, Streptococci pictured above, can give you strep throat! Fungi Mushrooms, mold and mildew are all examples of organisms in the kingdom fungi. Most fungi are multicellular and consists of many complex cells. Fun Facts about Fungi
  • 5. Some fungi taste great and others can kill you! Fungi are organisms that biologists once confused with plants, however, unlike plants, fungi cannot make their own food. Most obtain their food from parts of plants that are decaying in the soil. Protists Slime molds and algae are protists. Sometimes they are called the odds and ends kingdom because its members are so different from one another. Protists include all microscopic organisms that are not bacteria, notanimals, not plants and not fungi. Most protists are unicellular. You may be wondering why those protists are not classified in the Archaebacteria or Eubacteria kingdoms. It is because, unlike bacteria, protists are complex cells. These delicate looking diatoms are classified in the protist kingdom.