The document summarizes the evolution of classification systems for living organisms from early systems proposed by Linnaeus and Haeckel to more modern systems proposed by Whittaker and Woese. It describes Whittaker's five kingdom system which divided organisms into Monera, Protista, Fungi, Plantae, and Animalia. It then discusses how Woese proposed splitting Kingdom Monera into the domains of Archaea and Eubacteria based on genetic studies, establishing the current three domain system of Archaea, Bacteria, and Eukarya.

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2. MICROORGANISMA
Viruses Protozoa
Bacteria
Algae Fungi

3. Types of Classification
• Carlolus Linnaeus proposed the Two Kingdom
Classification in 1758.
• The two kingdoms consisted of:
– Plantae
– Animalia

4. THREE KINGDOM SYSTEM
• ERNEST HAECKEL‐1866
• KINGDOM PROTISTA:
– It includes unicellular & colonial eukaryotes such as
bacteria, algae, fungi & protozoans.
• KINGDOM PLANTAE:
– It includes multicellular photosynthetic plants.
• KINGDOM ANIMALIA:
– It includes multicellular animals.

6. Types of Classification.
• The next classification system that came
about consisted of 5 kingdoms.
• It was proposed by Robert Whittaker in 1969.
• The 5 kingdoms consisted of:
– Plantae
– Animalia
– Fungi
– Protista
– Monera

7. Robert Whittaker’s Five Kingdom System
• Plantae
– Plants are immobile, multicellular eukaryotes that
produce their food by photosynthesis and have
cells encased in cellulose cell walls.
– Examples: Ferns, pine trees, roses

9. • Animailia
– Animals are multicellular, heterotrophic
eukaryotes that are capable of mobility at some
stage during their lives, and that have cells lacking
cell walls.
– Examples: Humans, worms, spiders

11. Robert Whittaker’s Five Kingdom System
• Fungi
– Fungi are a eukaryotic, heterotrophic, usually multicellular group
having multinucleated cells enclosed in cells with cell walls.
– They obtain their energy by decomposing dead and dying
organisms and absorbing their nutrients from those organisms.
– Examples: Mushrooms, moulds, yeast
1

13. • Protista
• The most ancient eukaryotic kingdom, protista include a variety of
eukaryotic forms.
• Perhaps they are best defined as eukaryotes that are not fungi, animals,
or plants.
• Cell wall is usually absent, if present it is impregnated with silica
(diatoms).
• Photosynthetic or non photosynthetic.
• Locomotory structure may be cilia, flagella, pseudopodia or absent.
• Examples: , amoeba, diatom, euglena
Robert Whittaker’s Five Kingdom System

15. Protista
Paramecium diatom
amoeba euglena
2 3
4
5

16. Robert Whittaker’s Five Kingdom System
• Monera
–Monera are the only kingdom
composed of prokaryotic organisms,
they have a cell wall, and lack both
membrane-bound organelles and
multicellular forms.
–Examples: Bacteria, blue-green
bacteria

18. Characteristics of Monera:
• Unicellular or filamentous prokaryotes
• Omni present (air, soil, hot springs, deserts,
deep sea, snow & as parasites)
• Cell wall is composed of polysaccharides &
amino acids(peptido glycons ormurein)
• Autotrophic (photo & chemosynthetic) &
heterotrophic (saprophytic & parasitic)
• Reproduce by vegetative, asexual & sexual
methods

19. • MAJOR GROUPS OF MONERA:
1. Archaebacteria: Methanogens,
Halophyles, thermoacidophyles
2. Eubacteria: Vibrio, mycobacteria
3. Cyanobacteria: Nostoc, Anabena
1
9
HalobacteriumVibrioAnabenaNostoc
6 7 8 9

20. Types of Classification Systems cont..
• In the 1970’s, microbiologist Carl Woese, among other
researchers conducted studies and concluded that a group of
prokaryotic microorganisms called archaebacteria are
separate from other monerans.
• Therefore, they decided to split kingdom monera into two
separate kingdoms:
– Eubacteria
– Archaebacteria

21. • Archaebacteria
– Unicellular
– Prokaryotic
– Exist in extreme environments – they do not
need oxygen or light to live
– Examples: methanogens, extreme thermophiles,
extreme halophiles
• Eubacteria
– Unicellular
– Prokaryotic
– Heterotrophic, autotrophic, and chemotrophic
– Examples: Bacteria, cyanobacteria (blue-green
bacteria)

22. Three Domain System
• The Three Domain System, developed by Carl Woese,
is a system for classifying biological organisms.
• Over the years, scientists have developed several
systems for the classification of organisms.
• From the late 1960's, organisms had been classified
according to a Five Kingdom system.
• This classification system model was based on
principles developed by Swedish scientist Carolus
Linnaeus, whose hierarchical system groups organisms
based on common physical characteristics.

23. Comparison of Classification Systems
• Five Kingdom System
Kingdoms: Monera, Protista, Fungi, Plantae, and Animalia.
Three Domain System
• Archaea Domain
– Archaebacteria Kingdom
• Bacteria Domain
– Eubacteria Kingdom
• Eukarya Domain
– Protista Kingdom
– Fungi Kingdom
– Plantae Kingdom
– Animalia Kingdom

24. References
Books:
1. Biology of microorganisms By M. T. Madigan, J. M. Martinko, D. A.
Stahl and D. P. Clark
Images:
1. https://lh4.ggpht.com/BL8zyuw37iAzWft6GzMuHTWQ7LmX1pGCKxaXjY_wF8R
uMzVbHGnNAsu-XFO-r6w_ozc8hHM=s125
2. http://cfb.unh.edu/phycokey/Choices/Amoebae_Flagellates_Ciliates/Ciliates/P
ARAMECIUM/Paramecium_05_600x395_caudatum.jpg
3. http://www.bodc.ac.uk/projects/uk/mfmb/introduction/images/diatoms.jpg
4. http://www.microscopy-uk.org.uk/mag/imgsep01/amoebaproteus450.jpg
5. https://lh6.ggpht.com/mkGhpDrT154r8rgB0tTM4wfgOG0-
ULTlnUzmbRT7pvKbgVUoTrBC9XuJEqxTdQkEniP1jQ=s170
6. http://www.ohio.edu/plantbio/vislab/algaeimage/jpegs/nost1nitr.JPG
7. http://protist.i.hosei.ac.jp/PDB/images/Prokaryotes/Nostocaceae/Anabaena/A
nabaena9c.jpg
8. https://s3.amazonaws.com/healthtap-public/ht-
staging/user_answer/reference_image/8742/large/Cholera.jpeg?1344948822
9. http://plantphys.info/organismal/lechtml/images/halobacterium.jpg

25. Thank you