Hello, readers!
Today let's understand Classification of Living things.
Biological classification of plants and animals was first proposed by Aristotle.
Linnaeus classified all living organisms into two kingdoms - Plants and Animals.
Robert whittaker proposed an elaborate five kingdom classification: Monera, Protista, Fungi, Plantae and Animalia.
Monera: unicellular, prokaryotic, autotrophic or heterotrophic organisms. Eg bacteria
1. Archaebacteria: Halophiles, thermoacidophils, methanogens etc.
2. Eubacteria: Autotrophic bacteria, heterotrophic bacteria etc.
Protista: unicellular, eukaryotic, autotrophic or heterotrophic organisms.
1. Chrysophytes: plant like, golden algae and diatoms.
Diatoms have soap-box like silica shells.
2. Dinoflagellates: plant like, red, yellow, green, brown or blue cells. May have strong cellulose plates with two flagella.
3. Euglenoids: plant like, has protein pellicle layer on cell. May have two flagella, a long and a short.
4. Slime moulds: fungus like, saprophytes, collectively called plasmodium - spores are formed for reproduction in unfavorable conditions.
5. Protozoa: animal like, predators or parasites,
Amoeboid protozoa, flagellated protista, ciliated protozoa and sporozoans.
Fungi:
Multicellular, eukaryotic, heterotrophic organisms.
1. Phycomycetes: aseptate and coenocytic mycelium
2. Ascomycetes: mycelium is branched and septate,
3. Basidiomycetes: mycelium branched and septate,
4. Deuteromycetes: mycelium branched and septate, only asexual reproduction is discovered in them.
Plantae: multicellular, eukaryotic, autotrophic organisms with cell wall of cellulose. Shows alternation of generation
Animalia: multicellular, eukaryotic, heterotrophic organisms without cell wall.
Viruses, viroids, prions and lichens are not included in any of the five kingdoms.
