Classification of Organism

There are millions of organisms. it is impossible to study each individual separately.Classsification means to categories organism into different groups. Study of an individual of a group gives us the idea of rest of the member of the group.

Linnaeus (known as father of taxonomy) divides all organism into two kingdoms

  • Planate

  • Animalia

But this division cannot explain the position of organism like bacteria,virus,fungi and euglena,there is need of reconsideration of system of classification

Five Kingdom Classification

Five Kingdom Classification was proposed in 1969 by R.H.Whittaker. The Criteria of classifying organism into five kingdoms are its complexity of cell structure, complexity of body of organism, mode of nutrition .life style and phylogenetic relationship.

Living world

Monera:- It includes all prokaryotic organism like bacteria,cynobacteria and archiobacteria. Filamentous bacteria also come under this kingdom.All the organism in this kingdom are microscopic.

Protista:-This Kingdom includes unicellular form usually found in aquatic habitats. On the basis of mode of nutritution they are autotropic,parasitic and saprophytic. Diatoms flagellates and protozoa come under this kingdom.Euglena have both heterotropic and autotrophic mode of it is placed between plant and animal

Fungi:-This Kingdom includes non green plants. It has saprophytic nutrition and growing on dead and decaying organic matters.the cell wall is composed of chitin. Example:-Mushrooms, Mucor and Albugo etc.

Planatae:-This kingdom includes all plant except some algae,diatoms,fungi and member of monera and protista

Animalia:-Almost all animal comes under this kingdom except protozoan

Binomial nomenclature

There was  need of uniform  international naming of organism.In biology every organism is given two proper names.The first name is genus name  always started with capital letter and second is species started with small letter For Example Scientific name of human is homo sapiens

Homo is the name of genus,whose one species is sapiens

 Scientific name of some organism:-

Man                             Homo sapiens

Cat                              Felis domestica

Frog                             Rana tigrina

Dog                             Canis familaris

Cow                             Bos indicus

Mango                         Mangifera indica

Wheat                          Triticum aestivum

Gram                           Cicer arietinum

Housefly                      Musca domestica

Rice                             Oryza sativa

Pea                              Pisum sativum

Mustard                       Brassica campestris