exploring classification and the six kingdoms of life!1 million types of bacteria of which only...
TRANSCRIPT
When Carolus 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, so he developed a new
one.
Today the current system of classification
includes six kingdoms that are placed within
three domains. The three domains are
Archaea, Bacteria and Eukarya.
#1: Archaea: Archaea is the Domain that all
Archaebacteria are classified under.
Approximately 4% of all organisms are Archaea.
This domain only includes one Kingdom: Archaea
(also called archaebacteria).
#2: Bacteria: Bacteria is the Domain that all
other bacteria are classified under. The
kingdom is called Bacteria or Eubacteria.
Approximately 7% of all organisms on earth
are bacteria. There are estimated to be about
1 million types of bacteria of which only 4,000
have been identified. These include bacteria
that are decomposers and non-harmful
bacteria that help our bodies, as well as
disease causing bacteria. This Domain only
includes one Kingdom: Bacteria or Eubacteria.
#3: Eukarya: Eukarya is the Domain that all
eukaryotes (organisms with an organized
nucleus) are classified under. Approximately
89% of all organisms are eukaryotes. In the
Eukaryota Domain, there are about 12.4 million
species. This Domain includes four Kingdoms:
Animals, Plants, Fungi, and Protista.
Click the Living Things picture to the left to
learn more about the three domains.
The six kingdoms are: Archaea, Bacteria,
Protista, Fungi, Plantae, and Animalia.
How are organism placed into their kingdoms? There are four ways: #1 Cell type (presence of a nucleus in the cell) All organisms are made of cells which carry on the functions necessary to sustain life. A cell is the basic unit of structure and function in an organism. Just as our bodies are made up of many structures (parts) that work together, cells have many structures (parts) that do the same. The structure is the parts it is made of and how it is put together. The function is the job each structure performs.
Exploring Classification
and The Six Kingdoms
of Life!
Prokaryotic Cells:
Organisms called Prokaryotes do not have an organized structure called a nucleus that contains genetic material and controls the cell. The genetic material just floats around inside of the cell. Pro = “before” and karyote = “nucleus”, no nucleus. You can remember that Pro rhymes with No for “NO” nucleus. Bacteria are examples of prokaryotes. Eukaryotic Cells:
Organisms called Eukaryotes do have an organized structure called a nucleus that contains genetic material and controls the cell. Eu = “true” and karyote = “nucleus”, true nucleus. You can remember that Eu rhymes with true and nu. Animals, plants, Fungi, and Protists are examples of eukaryotes. #2 Ability to make food Autotroph/Producers:
Organisms that make their own food;. Auto- means “self”, and –troph means “feeder.” Therefore, an autotroph is a self-feeder. They use the food they make as an energy source to carry out their life functions.
Examples are plants that make their own food by transforming the radiant energy from the Sun to chemical energy through the process of photosynthesis. Some bacteria are autotrophs. They use chemicals in their environment to make their own food. Some Protists, such as Euglena, can make their own food. They contain a structure called a chloroplast, and they use sunlight for photosynthesis. Heterotroph/Consumers:
Organisms that cannot make their own food are called heterotrophs. Hetero-means “other” and –troph means “feeder”. A heterotroph must feed off of others. They get their energy from eating autotrophs (plants) or eating other heterotrophs. Examples are animals, mushrooms, and molds. Euglena are able to consume food when light is not present. Heterotrophs transfer the chemical energy from food into other forms of energy they can use. #3 The number of cells in their body Unicellular:
All organisms are composed of cells. Unicellular organisms are single-celled (one). Uni = “one”. This one cell carries out all of the functions necessary to keep the organism alive. Bacteria
are examples of unicellular organisms. Many Protists are unicellular as well.
Multicellular:
All organisms are composed of cells.
Multicellular organisms are made of many cells.
Multi = “many”. All of the different cells are
specialized to do certain tasks. Humans have
skin cells, brain cells, and blood cells, just to
name a few. Animals and plants are examples
of multicellular organisms. Most Fungi are
multicellular, and a few Protists are as well.
#4 How an organism reproduces (makes more
offspring)
Asexual Reproduction:
Genetic material is passed from parents to
offspring (babies) during reproduction. Asexual
reproduction is a process that only involves
one parent, not two. A = “not”, not sexual.
The offspring will be identical to their
parent. The genes of the offspring are
exactly like the parent’s genes. Bacteria are
examples of organisms that reproduce
asexually. Bacteria will divide in half to form
two cells identical to the original cell. This is
called fission. Some plants, Fungi, and Protists
can reproduce asexually. In rare instances,
there are animals such as the sea anemone
that can reproduce asexually.
Sexual Reproduction:
Genetic material is passed from parents to offspring (babies) during reproduction. In sexual reproduction, offspring result from the combination of genetic material from two parents- a male and a female. They get half of the genetic material from each parent. The sperm from the male contains half of the genetic material, and the egg from the female contains half of the genetic material. Because offspring inherit a combination of genetic material from both parents, they are not exactly like either parent. Animals and most plants reproduce sexually. Some Fungi and Protists can reproduce sexually. A Paramecium is an example of an organism that can produce sexually or asexually.
Kingdom Archaea (archaebacteria)
In 1983, scientists took 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 celled) organisms in
the samples. These organisms are today
classified in the kingdom Archaea.
.
Archaebacteria are prokaryotes that live
in extreme environments such as volcanic
vents, arctic temperatures, and hot
springs. Some examples are halophiles and
thermophiles. They can be autotrophic or
heterotrophic. They reproduce asexually.
They are called extremophiles. Can you
guess why?
Finding Archaea: The hot springs of
Yellowstone National Park, USA, were among
the first places Archaea were discovered. The
biologists pictured above are immersing
microscope slides in the boiling pool onto
which some archaea might be captured for
study. Click on the image above to learn more
about archaea and why they are called
extremophiles, are considered our oldest
relatives, and how they are responsible for
the colorful phenomenon below!
Kingdom Bacteria (Eubacteria)
Click on the image to
watch a fantastic
introduction video
about bacteria!
Like archaea, bacteria are single celled. They
are found everywhere and people are quite
familiar with them, including you!
Bacteria are classified in their own kingdom
because their chemical makeup is different.
Most Bacteria are helpful. Some produce
vitamins and foods like yogurt. However, the
bacteria, Streptococci pictured above, can give
you strep throat! Ouch!
Some of these bacteria are decomposers
which play an important and helpful role in
our ecosystem. Some are autotrophs while
others are heterotrophs. They reproduce
asexually. Most live in moderate environments.
Click on the Bacteria image and listen as the
Amoeba Sisters share more information on
Bacteria with you!
Kingdom Protists (Protista)
Click on the Protist image above for a
dynamic introduction to this odd kingdom!
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, not animals, not plants and not
fungi. Protista are eukaryotes. Some are
unicellular, and some are multicellular. Many of
these organisms are microscopic such as
Amoeba, Paramecium, and Euglena. Some are
autotrophs and others are heterotrophs. They
can reproduce sexually or asexually.
You may be wondering why those protists
are not classified in the Archaea or Bacteria
kingdoms.
It is because, unlike archaea and bacteria,
protists are complex cells.
These
delicate
looking
diatoms
are
classified
in the
protist
kingdom.
Kingdom Plants (Plantae)
Click the image above for an awesome introduction to 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 all multicellular and consist of complex cells. Plants are also eukaryotes. All plants are autotrophs (producers), but in a few rare cases, some are also heterotrophs (Venus flytrap); however, they do not get their energy from the flies they trap. Some plants produce flowers, while others do not. Examples of plants are grass, trees, vegetable plants, and weeds. They can reproduce sexually or asexually. With over 250,000 species, the plant
kingdom is the second largest kingdom. Plant
species range from the tiny green mosses to
giant trees. Check out the world’s 7 largest
trees by clicking the image below.
Without plants, life on Earth would not exist!
Plants feed almost all the heterotrophs
(organisms that eat other organisms) on
Earth. Wow!
Learn more about plants by watching the
video below AND check out the top 10
strangest plants on earth!
Kingdom Fungi
Mushrooms, mold and mildew are all examples
of organisms in the kingdom fungi. They are
eukaryotes. Many are multicellular, but some
are unicellular. All are heterotrophs. Most feed
on dead or decaying organisms. They are found
almost everywhere on land, but some live in
water. They can reproduce sexually or
asexually.
Learn about fungal infections like ringworm
by clicking the harmless little fungi above.
Fun Facts about Fungi
Click above to learn more about
these FUN-GUYS!
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.
Kingdom Animals (Animalia)
The animal kingdom is the largest kingdom with over 1 million known species. See some by clicking below!
Sumatran Tiger - Kingdom: Animalia, Phylum, Chordata,
Class Mammalia, Order Carnivora, Family Felidae, Genus
Pathera, Species tigris
Members of the animal kingdom are found in
the most diverse environments in the world.
Animals Dogs, cats, fleas, and sea coral are
examples of animals. They are multicellular
eukaryotes that are heterotrophs
(consumers). Most, but not all, animals can
move from one place to another. Most
reproduce sexually, but some may be asexual
(sea anemones, whiptail lizards and some
fish, among others).
Check out live animal cams here!
And here!
And here!
And here!
And, here (Berry College in Rome, GA)
Check out reptiles here!
And Insects here!