Five Kingdom Classification System


What is the Five kingdom classification system?

  1. R.H. Whittaker put forth the five kingdom classification system which helped classify various organisms easily. The five kingdoms were:

(i) Kingdom Monera

  • This kingdom harbours a variety of microorganisms which belong to the prokaryotic category.
  • Cells, in this kingdom, do not have a well-defined membrane system and lack a proper nucleus and membrane-bound
  • The genetic material in these organisms is scattered throughout the cytoplasm and is called the Nucleoid. The other organelles are also scattered throughout the
  • Subtypes of this kingdom include archaebacteria and eubacteria.
  • Archaea are the most primitive forms found even in extreme environmental conditions like hot springs and the Dead
  • Eubacteria are the true forms of bacteria that are present everywhere around us. These are the beneficial ones as well as the harmful parasitic
  • So, all the bacteria, in general, are included in this

         Prokaryotic Cell               Archaebacteria       Eubacteria

  • Kingdom Protista
    • This kingdom contains organisms which are unicellular and
  • Protists have a well-defined cell system with a proper membrane-bound nucleus and organelles as
  • Apart from the usual organelles, protists also have specialised structures like the single flagellum or several cilia which help in locomotion of the single
  • Unicellular organisms like the amoeba, paramecium, diatoms and others are included in

this kingdom.

  Prokaryotic Cell                       Protists

  • Kingdom Fungi
    • This kingdom includes all the fungi. They are microscopic organisms and
    • They have a well-defined cell wall which is usually made up of a complex sugar called

Chitin. The cells are generally multicellular at certain stages in their lives.

  • This typical structure of a fungus shows the presence of a bag-like structure called

Sporangium containing the fungal spores.

  • The fungal stalk is made up of thin thread-like structures called hyphae. These hyphae, together, form a network which is called the Mycelium.
  • The fungal body is usually divided into three parts – head, stalk, and
  • Some fungi also have a symbiotic association with other

For example, lichen is a symbiotic association of fungi and algae.

         Fungi                                           Lichens

  • Kingdom Plantae
    • This kingdom harbours the simple as well as complex
    • They are multicellular organisms and eukaryotic and are capable of preparing their own food.

                      Plants

  • Kingdom Animalia
    • This kingdom consists of complex, multicellular organisms –
    • They have a very complex body and are considered as one of the highly evolved organisms among

                   Animals