Download Classification of Kingdoms Lab

Name ________________________
Period _______ Date ___________
Classification of Life
In classifying organisms, scientists first divide them into very large groups called Kingdoms.
In the 1700’s Linnaeus divided all living things into two groups – the plant kingdom and the animal
kingdom. The organisms were grouped on the basis of the structures they possessed. Linnaeus
devised his classification system 100 years before Darwin published his theory of evolution by natural
selection. Thus, Linnaeus did not realize that the structural similarities that he used to classify
organisms resulted from their common evolution. As the use of the microscope increased, organisms
were discovered that seemed to fit neither into the plant kingdom nor animal kingdom. Euglena, for
example, carries on photosynthesis and resembles a plant yet it also moves and can ingest food, thus
resembling an animal. In 1866, Ernst Haeckel proposed the creation of a third kingdom, the Protista.
This kingdom included all one-celled organisms and other organisms that had characteristics of both
plants and animals.
1. What is a Kingdom? _________________________________________________________
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2. Why did Haeckel create the Protist Kingdom? _____________________________________
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The Protist Kingdom did not clearly show the evolutionary relationship among organisms. In
1937, Edouard Chatton suggested dividing things into two major groups, Those with nuclei and those
without. Organisms with a membrane-bound nucleus in their cells are called eukaryotes.
Eukaryotes also contain other membrane-bound organelles, such as chloroplasts and mitochondria.
Organisms that lack a nuclear membrane are called prokaryotes. Although prokaryotes may be
photosynthetic, they lack chloroplasts and have no mitochondria. Chatton’s system is based on the
thesis that the presence or absence of membrane bound organelles is more important in establishing
evolutionary relationships than is the difference between plants and animals.
3. Distinguish between a prokaryote and a eukaryote. _________________________________
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Classification systems have been modified as information concerning evolution has changed.
In 1969, Robert Whittaker proposed a five-kingdom system in which organisms were grouped as
Monera, Protista, Fungi, Plantae or Animalia. This system takes into consideration Chatton’s thesis
that prokaryotes and eukaryotes should be placed into separate kingdoms.
4. What are the five kingdoms proposed by Whittaker? _________________________________
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Further studies of bacteria however, have shown that there are two important subtypes with
very different morphologies and properties. Recognition of these two broad types of bacteria has
driven the acceptance of a newer six-kingdom system. Now all organisms are grouped as
Archaebacteria, Eubacteria, Protista, Fungi, Plantae or Animalia.
5. Name the two subtypes of bacteria. What same kingdom did they both used to belong?
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The Kingdom Archaebacteria include bacteria that live in harsh environments such as
sulfurous hot springs, salty lakes and the intestines of animals. The prefix archae comes from the
Greek work for ancient. These bacteria are thought to have descended from the first organisms on
earth. Kingdom Eubacteria are the most abundant bacteria and can cause tooth decay, turn milk
into yogurt and cause food poisoning. Both are prokaryotic and unicellular. Some are photosynthetic.
None ingest their food but some may absorb it. The Kingdom Protista includes protozoa, small
nucleated algae, seaweed and slime molds. All organisms are eukaryotic. Most are unicellular.
Many are motile at some point in their life cycle. Many ingest their food and others are
photosynthetic. The Kingdom Fungi include molds, yeasts and mushrooms. They are eukaryotic
and many reproduce by spores. None are photosynthetic and they secrete digestive enzymes and
absorb their food. Most are multicellular. The Kingdom Plantae include the mosses, ferns, conebearing plants, and flowering plants. All organisms are photosynthetic, eukaryotic, multicellular and
have cellulose cell walls. Many have specialized tissues that aid in the transport of water through the
plant. Reproduction is by spores (mosses and ferns) or seeds (conifers and flowering plants). Most
lack the ability to move from place to place. The Kingdom Animalia consists of many different
multicellular forms. It includes vertebrates and invertebrates. Most can move about aided by nerve
and muscle cells. Most have specialized sense organs. All organisms obtain their nutrition from an
outside source. Many have highly specialized digestive systems. None are photosynthetic and all
animals are eukaryotic.
Kingdom
Archaebacteria
Eubacteria
Protista
Fungi
Plantae
Animalia
Prokaryote
or
Eukaryote
Multicellular
or
Unicellular
Means
of
Nutrition
Other
Significant
Characteristics
Examples