The 6 Kingdoms
Every living creature on Earth belongs to a kingdom. Scientists debate how many kingdoms there are, but most agree there are six. Here is how the six kingdoms are organized.
Archaebacteria are bacteria with internal membranes and are found in deep-ocean thermal vents, hot springs in Yellowstone, and brine marine environments.
Eubacteria are single-celled organisms that don’t have a nucleus. Bacteria make up the entire kingdom. There are more forms of bacteria than any other organism on Earth. Some bacteria are beneficial to us, such as the ones found in yogurt. Others can cause us to get sick.
Protists are mostly single-celled organisms that have a nucleus. They usually live in water. Some protists move around, while others stay in one place. Examples of protists include some algae, paramecium, and amoeba.
Fungi are usually motionless organisms that absorb nutrients for survival. They include mushrooms, molds, and yeasts.
Plants contain chlorophyll, a green pigment necessary for photosynthesis, a process in which plants convert energy from sunlight into food. Their cell walls are made sturdy by a material called cellulose, and they are fixed in one place. Plants are divided into two groups: flower- and fruit-producing plants and those that don’t produce flowers or fruits. They include garden flowers, agricultural crops, grasses, shrubs, ferns, mosses, and conifers.
Animals are the most complex organisms on Earth. Animals are multi-celled organisms, eat food for survival, and have nervous systems. They are divided into vertebrates and invertebrates and include mammals, amphibians, reptiles, birds and fish.
Kingdom is the highest rank used in the biological taxonomy of all organisms. There are 6 kingdoms in taxonomy. Every living thing comes under one of these 6 kingdoms. The six kingdoms are Eubacteria, Archae, Protista, Fungi, Plantae, and Animalia.
Until the 20th century, most biologists considered all living things to be classifiable as either a plant or an animal. But in the 1950s and 1960s, most biologists came to the realization that this system failed to accommodate the fungi, protists, and bacteria.
By the 1970s, a system of Five Kingdoms had come to be accepted as the model by which all living things could be classified.
At a more fundamental level, a distinction was made between the prokaryotic bacteria and the four eukaryotic kingdoms (plants, animals, fungi, & protists).
The distinction recognizes the common traits that eukaryotic organisms share, such as nuclei, cytoskeletons, and internal membranes.
Although many books and articles still refer to them as "Archaebacteria", that term has been abandoned because they aren't bacteria -- they're Archaea.
TYPES OF ORGANISMS
Prokaryotic, unicellular organisms
unicellular and colonial--including the true bacteria (eubacteria)
asexual reproduction -- binary fission
no cell nucleus nor any other membrane-bound organelles within their cells, most but not all have a cell wall e.g., thermoplasma, ferroplasma
halobacteria, ARMAN (Archaeal Richmond Mine Acidophilic Nanoorganisms), thermoplasma, ferroplasma
Archaea reproduce asexually by binary or multiple fission, fragmentation, or budding; meiosis does not occur
Green, golden, red, and brown unicellular algae large, single eukaryotic cell (nucleus is enclosed by a membrane)
protozoans and algae of various types
asexually with binary fission
sexually --, two individuals join and exchange genetic material in the nucleus
multicellular,with a cell wall, organelles including a nucleus, but no chloroplasts. They have no mechanisms for locomotion. Fungi range in size from microscopic to very large ( such as mushrooms). Nutrients are acquired by absorption, for the most part, from decaying material.
funguses, molds, mushrooms, yeasts, mildews, and smuts
sexual and asexual
multicellular form with specialized eukaryotic cells; do not have their own means of locomotion
seaweeds and kelp, mosses, liverworts, spores plants (club mosses & ferns), gymnosperms, and flowering plants
Sexual reproduction involves the male pollen grains traveling to the stigma of a flower
Asexual reproduction involves the production of a new plant without the use of flowers.
multicellular form with specialized eukaryotic cells; have their own means of locomotion
sponges, coelenterates, flatworms, roundworms, mollusks, annelids, arthropods, echinoderms and chordates, Humans, Elephants, Ants, Bees, Naked Mole rats
sexual reproduction through fertilization
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
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.
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!
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, Genus Pathera, Species tigris
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.
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.
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!
Mushrooms, mold and mildew are all examples of organisms in the kingdom fungi.
Most fungi are multicellular and consists of many complex cells.
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.
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.