Transcript The 5 Kingdoms of

6
The 5 Kingdoms of
There are millions of living organisms on Earth...
and humans, in their sense of wonder, have tried for centuries
to see some order in the chaos of these multitudes.
The early Greeks tried to classify all inanimate objects as fire, air, earth,
and water, and the Greek philosopher Aristotle further classified living
The efforts
classify
living
things
as eitherto
Plant
or Animal.
Hethings
groupedsaw
animals into Land Dwellers,
Water
andin
Airthe
Dwellers.
didn't work very well, as this system
greatDwellers,
progress
work This
of Carl
grouped
elephants
andbook
earthworms,
whales and water striders, flies and
Linnaeus,
whose
Systema
falcons. These things aren't alike!
Naturae ("The Natural Classification",
Botanists
later
tried
to classifyconcept
living creatures
based on
his
religious
that by means of locomotion,
grouping butterflies and bats (flying), barnacles and barley (both rooted in
you could understand God by studying
place). This system of classification didn't work out very well, either (bats
nature,
his creation),
was published
inso other attempts were
and
butterflies
are pretty different,
aren't they?),
made.
1735.
While some of his concepts have been significantly
changed, we still keep much of his ideas (hierarchical
classification and system of binomial nomenclature). Let's
pretend we are young botanists like Carl Linneaus and see
how we might classify living things that we know at
Cazadero.
p n
l t
a s
a
This process is called photosynthesis,
n
and may be one of the most important
l
chemical reactions on the face of thei
earth.
s
m
a
The most obvious grouping is into two groups, plants and animals
This system works well until...
This classification works rather well, and for many years we were all taught about
the Plant Kingdom and the Animal Kingdom in school. Plants, such as redwood
trees, are characterized not by the fact that they don't run around, but by the fact
that they all make their own food out of sunshine, water, and carbon dioxide, by
means of chlorophyll (the stuff that makes plants green).
Animals, on the other hand, either eat plants (such as deer) or they eat other
animals that do eat plants (such as mountain lions who eat the deer). This
classification system works pretty well, and we still talk about deer as being
members of the Animal Kingdom and redwood trees as being members of the Plant
Kingdom.
...until you try to classify a
mushroom!
Hmmm. Let's see. It's not green. Scientists tell us it
So we
needit to
add
Fungi
Kingdom
that's
because
does
notthe
contain
chlorophyll.
It
to the make
PlantitsKingdom
and
the be
Animal
doesn't
own food, so
it can't
a plant. We
learned
that all
plants
their
own food.
Kingdom.
Now
wemake
have
three
kingdoms.
But it doesn't eat, either: mushrooms don't have
mouths!
So it can't be an animal, because we learned that all animals eat food. So
how do mushrooms get their nourishment? Mushrooms are a type of
fungus, and all fungi (the plural of "fungus") neither make food nor eat it:
they absorb it.
This
system
works
well
until...
Almost all of the body of a mushroom is actually underground, made up of
tiny little strings of cells called hyphae. They are so tiny that they are only
1/50th the diameter of a human hair! How's that for small? The hyphae
grow out until they run into something that the fungus thinks is tasty, and
the hyphae grow into the food (mostly dead plant and animal matter) and
absorb its nutrients directly into its own cells.
...until you try to classify bacteria!
Actually, bacteria are found everywhere but you
can't see them anywhere because they are so small.
Millions of them are in a single drop of water.
So we need to add the Monera Kingdom
Bacteria are very different from plants, animals, and
and now we have four kingdoms.
fungi, and not just because of size. All of the other living
things (plants, animals, fungi) are made up of thousands,
or billions, or even eleventeen gazillions, of cells, and
each of their cells has a nucleus (the scientists call this
"eukaryotic"), a central command center that tells the cell
what to do. Bacteria are always made up of just one cell,
and their cell has no nucleus (the scientists call this
"prokaryotic"). Bacteria are actually more different from
plants and animals than a mouse is from an elephant!
They really need to be in their very own kingdom, the
Kingdom Monera ("monera" comes from the Greek word
for "single", referring to the fact that these organisms are
all single-celled.)
This system works well until...
 High-powered microscopic views of bacteria (artificially colored)
...until you try to classify slime!
Wherethe
doKingdom
you stick
slime?
Algae need their own kingdom,
Prostista.
This group is also the
Paramecium,
a protist
swims
around
in
(I mean,
after you
scrape
it offthe
the
bottom
ofthat
your
shoe!)
home of other
organisms
that don't
fit into
other
kingdoms,
including
singlewaterand multi-cellular organisms like
celled organisms like paramecia andpond
diatoms,
So we giant
added
Protist
and
on the
the tree
of life doKingdom
you place slime,
kelp (which are just Where
algae).
or more
called algae?
now we have
five properly
kingdoms.
It is not an animal, because it does not eat things. It is not a plant, either, because it
does not develop as a seed or spore within the mother plant. It is not a fungus,
because it is green, and has chlorophyll, and can make its own food. And it is not a
bacteria, because is has a cell nucleus. What is it?
Volvox, a single-celled algae from a pond
This system works well until...
So we need to add the Kingdom
Prostista to Plant Kingdom, Animal
Kingdom, Fungi Kingdom, and
Kingdom Monera. This five kingdom
classification of living organisms is a
good scheme with which to look and
and learn about the wonderful world
Diatom, a single-celled protist that floats in water
we live in.
and comes in the most bizarre shapes
Scientists began to research the Monera (bacteria) Kingdom further.
They discovered that there were two distinctly different kind of bacteria
and so the Monera Kingdom was split into two separate kingdoms:
Archaebacteria and Eubacteria
Archaebacteria are those
that live in extreme
environments like the
ocean floor, and even
your intestines!
Eubacteria have a different
chemical makeup than
archaebacteria and are often
helpful, like those found in
yogurt.
So, there you have it. The six kingdoms of life.
Let’s Review…
The 6 Kingdoms of
Animals
Fungi
Plants
Protists
Archaebacteria
Eubacteria
The Kingdoms of Life can be diagrammed, with their relationships to
each other and to the presumed origin of life: