Five Kingdoms of Organisms

Till recently, there were only two kingdoms for classification - Plantae and Animalae. Such a two kingdom classification had several drawbacks. For example, bacteria and fungi were kept along with plants although they are very different.

In 1969, R.H. Whittaker suggested the five kingdom classification which is based on the following three criteria:

• (i) The presence or absence of a well-defined nucleus
• (ii) Unicellular or multicellular
• (iii) Mode of nutrition

The five kingdoms are:

1. Monera
2. Protista or Protoctista
3. Fungi
4. Plantae
5. Animalae