The three domains of life
The Earth is 4.6 billion years old and microbial life is thought to have first appeared between 3.8 to 3.9 billion years ago. 80% of Earth's history was exclusively microbial life. Undoubtedly, mic...
Overview:5 kingdoms of classification
R.H. Whittaker came with the concept of five kingdoms of classification that takes into account of cell structure, the presence of cell wall, mode of nutrition, mode of reproduction and many others.
Note: Shift sideways to see the other kingdoms
| Characters | Monera | Protista | Fungi |
Plantae | Animalia |
| Cell type | Prokaryotic | Eukaryotic | Eukaryotic |
Eukaryotic |
Eukaryotic |
| Cell wall | Non cellulosic (polysaccharides+Amino acids) | Present in some | Present (fungal cellulose or chitin) | Present (cellulose) | Absent |
| Nuclear membrane | Absent | Present | Present |
Present |
Present |
| Cell organisation | Unicellular | Unicellular or multicellular | Unicellular or multicellular |
Multicellular | Multicellular |
| Body organisation | Cellular grade |
Cellular grade |
Tissue grade | Tissue or organ grade | Tissue/ organ/ system grade |
| Mode of nutrition | Heterotrophic (saprophytic/parasitic) and Autotrophic (chemosynthetic and photosynthetic) | Autotrophic (Photosynthetic) and Heterotrophic | Heterotrophic (Saprophytic/ parasitic) |
Autotrophic (Photosynthetic) | Heterotrophic (holozoic/saprophytic) |
| Respiration | Aerobic and Anaerobic (methanogens) | Aerobic | Aerobic and Anaerobic | Aerobic and rarely Anaerobic | Aerobic |
| Reproduction | Only asexual | Sexual and Asexual | Sexual and Asexual |
Sexual and Asexual |
Sexual ( most common)/Asexual |
| Movement | Both motile or non motile | Both motile or non motile |
Non motile | Non motile |
Motile |
| Reserve food | Oil and fat droplets | Oil and fat droplets |
Glycogen and fat | Starch/Protien | Glycogen/fat |
| Known as | Decomposers/ saprophytes | Planktons(autotrophs and heterotrophs) | Saprophytes/Parasites | Autotrophs | Heterotrophs |
| Role in ecosystem | Decomposers | Producer ,consumer and decomposer | Consumer and decomposer | Producer | Consumer |
| Example | E.coli, Anthrax bacterium | Giant klep, Paramecium, Euglena | Agaricus, Sac fungi | Snake plant, trees, shrubs | Humans, insects, birds, animals |
