While organisms in this kingdom have genetic material, it is not
enclosed or surrounded by a nuclear envelope. Therefore, these
organisms ‘technically’ do not have a nucleus. Their genetic material
is in the form of a single circular chromosome. All members of this
kingdom are single-celled or unicellular. Some are producers and can
“make their own food” through photosynthesis or chemosynthesis.
Technically, they can convert inorganic compounds, such as carbon
dioxide and water, into organic compounds, such as glucose. In the
process they give off oxygen as a byproduct. While these organisms
are autotrophic, many are heterotrophic. Depending on the species,
oxygen may be toxic, tolerated, or needed for their metabolism.
Except for one, all organisms in this kingdom have a cell wall
supporting their cell membrane. They reproduce asexually by splitting
in half which is called binary fission. They can exchange genetic
information through conjugation.
These are a diverse group of organisms living almost everywhere.
Many species are beneficial such as those that convert nitrogen into a
useable form for plants. Others, such as E. coli, aid with digestion.
While many are helpful, others are pathogenic causing diseases such as
cholera, strep throat, and tuberculosis. Antibiotics have been
developed to help attack infections caused by these organisms.
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They are called the “ancient ones”. These unicellular prokaryotes are
found in extremely harsh, even hostile, environments. Here they have
carved out a niche for themselves where other organisms fail to thrive.
Their cells are supported by cell walls. Many are autotrophic (but by
chemosynthesis not necessarily by photosynthesis). Depending on the
species, oxygen, hydrogen, carbon dioxide, or sulfides may be needed
for their metabolism. They reproduce asexually by binary fission.
They have been found living in the hot springs and geysers of
Yellowstone National Park as well as in the hot thermal vents of the
deep ocean. Others thrive in highly acidic or salty environments such
as the Dead Sea or the Great Salt Lake. Native to Yellowstone
National Park, the Taq bacterium can survive in very hot
environments and this property enables it to be used in genetic
engineering to copy large quantities of DNA commercially.
Commonly
called
“heat lovers”
or
“salt lovers”
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These multicellular organisms have specialized cells that that form
tissues. Their cells are complex and have nuclei with genetic material
within. No members of this kingdom have a cell wall. Trading the
extra rigid supportive boundary of a cell wall for flexibility and
motility, these organisms can move from place to place. Most
organisms in this kingdom reproduce sexually while a few have
retained the ability to reproduce asexually. Being heterotrophic, all
members are consumers and are dependent on ingestion of nutrients
for energy. Oxygen is needed for metabolism. Mammals, birds,
reptiles, fish, amphibians, as well as invertebrates belong to this
kingdom.
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These multicellular organisms have complex specialized cells that form
tissues. Their genetic material, which is encoded in chromosomes, lies
in the nuclei of their cells. All members are autotrophic or producers
by photosynthesis where they convert radiant or solar energy into
chemical energy that is stored in the bonds of glucose. Oxygen is
needed for metabolism. The cells of these organisms have cell walls
that give them extra support. They can reproduce sexually and
asexually. Mosses, ferns, conifers, and flowering plants belong to this
kingdom.
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All members of this kingdom are multicellular (except one) and used
to be classified as plants. However, they are classified into a kingdom
of their own because their cells lack chloroplasts making it impossible
for them to photosynthesize. Oxygen is needed for their metabolism.
Nuclei can be observed in their cells as well as many other organelles.
These organisms get their nutrients and energy by decomposing
decaying matter. These organisms reproduce sexually and asexually.
Cell walls give an extra boundary to their cells; however, they are
different in composition than the cellulose cell walls found in plants.
Mushrooms, mold, yeast, and mildews are all examples of organisms
that belong to this kingdom.
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Most organisms that belong to this kingdom are unicellular. Those
that are multicellular do not form true tissues. Their cells are quite
complex and have nuclei where genetic material can be found. Many
are aquatic. Some of these organisms lack a cell wall and therefore are
able to move actively. Others have a cell wall. Some are autotrophic
and others are heterotrophic. Oxygen is needed for metabolism. Most
reproduction is asexual though they can reproduce sexually.
Sometimes members of this kingdom are called the “left-overs” or the
“odds & ends” because they don’t seem to fit into any other kingdom.
This kingdom includes all microscopic organisms that are not bacteria,
not animals, not plants, and not fungi. Slime molds, algaes, such as
plankton, and protozoans such as paramecia, euglena, and amoeba
belong to this kingdom.
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