Carl Woese’s three kingdom classification.pptx

Carl woese proposed ‘three domain’ classification system’.
It is evolutionary model for phylogeny.
It is based on differences in rRNA nucleotide sequences, cell membrane lipid structure and sensitivity to antibiotics.
3 kingdoms are:
1. Eukarya
2. Archaea
3. Bacteria

1. Carl Woese’s three kingdom classification

2. Carl Woese’s three kingdom classification The five kingdom system does not explains how organisms within kibngdoms are related to each other. Early 1970s: Dr. Carl Woese and other scientists began to find evidence for prokaryotic organisms. These organisms were lived in extreme environments like deep dea hydrothermal vents, hot springs, dead sea, acid lakes, salt evaporation ponds. Bacteria in such extreme conditions were named “ archaebacteria (ancient bacteria”.

3. Carl woese proposed ‘three domain’ classification system’. It is evolutionary model for phylogeny. It is based on differences in rRNA nucleotide sequences, cell membrane lipid structure and sensitivity to antibiotics. 3 Domains 3. Eukrya 2. Bacteria 1. Archea

4. 1. ARCHEA Live in extreme environments. Include methanogens , extreme halophiles and hyperthermophiles . They can withstand higher temperatures and stronger acid concentrations. Characters: Prokaryotic Membrane composed of branched hydrocarbon chains attached to glycerol by ester linkages. No peptidoglycan in cell wall. Not sensitive to antibiotics that affect bacteria but are sensitive to some antibiotic that affects eukaryotes.

5. e. Contains rRNA that is unique to archea . Examples of archea : Methanogens : Use CO2, H and N to produce energy. Generates methane gas Lives in swamps, marshes, gut of cattle, termites etc. Methanococcus jannaschii , was first archean isolated from deep sea Alvin probe. They are decomposers and can be used in sewage treatment.

6. 2. Extremehalophiles (salt lovers) Requires salty environment (10 times salty than ocean). Some of them prefer 30% salt concentration. Lives in dead sea, the Great salt lake, salt evaporation ponds etc.

7. 3. Extreme thermophiles : They prefer temperature above 60 C or near or below freezing ( psychrophiles ). Thermophiles lives in sulphur springs, Yellowstone national park, deep sea hydrothermal vents, geothermal power plants etc. Examples: Thermus aquaticus and Pyrococcus furiosis Psychrophiles lives in ocean waters around Antartica , under polar ice caps etc

8. 1.BACTERIA ( Eubacteria ) Also known as “ true bacteria ”. Can be found almost everywhere. Characteristics: Prokaryotic Membrane composed of unbranched fatty acid chains attached to glycerol by ester linkages. Cell wall contains peptidoglycan Sensitive to traditional antibiotics but are resistant to antibiotics that affects eukaryotes. Contains rRNA that is unique to bacteria. Examples : Mycoplasma , cyaniobacteriam Gram + ve and – ve bacteria.

9. 3. EUKARYA ( Eukrayotes ) Characteristics: Eukaryotic Membrane composed of unbranched fatty acid chains attached to glycerol by ester linkages. Posses cell wall or lack it. Resistant to traditional antibiotics but are sensitive to antibiotics that affect eukaryotes. Contains rRNA that is unique.

10. EUKARYA PROTISTA FUNGI PLANTAE ANIMALIA

11. Kingdom Protista : Simple, unicellular and eukaryotic Examples: Molds, euglenoids , algae and protozoans 2. Kingdom Fungi: Unicellular or multicellular and eukaryotic. Possess cell wall Non-photosynthetic and obtains nutrients by absorption Examples: Yeast and molds

12. 3. Kingdom Plantae : Multicellular and eukaryotic Have cell walls Photosynthetic Examples : Mosses, ferns, conifers and flowering plants 4. Kingdom Animalia : Multicellular and eukaryotic Lack cell wall Heterotrophs Examples : Sponges, worms, insects and vertebrates