The phylogenetic analysis of RNA nucleotide sequences by Carl Woese led to a new version of " The tree of life". This now contained three domains, and 6 kingdoms.
Three Domains: Bacteria, Archaea, and EukaryaDomain Bacteria : Each bacteria has a cell wall, a plasma membrane, a cytoplasm lacking complex organelles, and at least one circular chromosome. ( With Kingdom Eubacteria)
- small
- single-celled
- prokaryotic
- usually have a cell wall
- usually reproduce by binary fission
*The oldest known fossils of cells appear to be bacterial cells
Domain Archaea: Found in extreme environments, scientists think that they were among the first organisms on Earth because of their unique adaptations ( With Kingdom Archaebacteria)
- single celled
- prokaryotic
- distinctive cell membranes
- unique biochemical properties
- some are autotrophic and are able to produce food by chemosynthesis
Domain Eukarya:
(Includes the kingdoms Protista, Fungi, Plantae, and anamalia)
- Eukaryotic cells
- large cells
- true nucleus
- complex organelles
Kingdoms: Eubacteria, Archaebacteria, Protista, Fungi, Plantae, Anamalia
Kingdom Eubacteria: Prokaryotic cells, cell walls containing peptidoglycan, cell membranes containing fatty acids, unicellular, heterotrophic and autotrophic by either photosynthesis or chemosynthesis
Kingdom Archaebacteria: means ancient bacteria, Prokaryotic cells, cell walls lacking peptidoglycan, cell walls containing hydrocarbons, unicellular, heterotrophic, autotrophic by chemosynthesis
Kingdom Protista: Protists, eukaryotic cells that are not plant, animals, or fungi.
Kingdom Fungi: Eukaryotic cells, Unicellular or multicellular, gain nutrients by absorbing rather than ingesting, cell walls made of chitin, cell membranes contain fatty acids.
Kingdom Plantae: Eukaryotic, Multicellular plants, autotrophic, cell walls from cellulose,
cell membranes contain fatty acids
Kingdom Animalia: Eukaryotic, Multicellular, heterotrophic, symmetrical body organization