Briefly discuss on five kingdom classification. Add a note on merits and demerits.

Explanation

R.H.Whittaker, an American taxonomist proposed five kingdom classification in the year 1969. The Kingdoms include Monera, Protista, Fungi, Plantae and Animalia (Figure 1.1). The criteria adopted for the classification include cell structure, thallus organization, mode of nutrition, reproduction and phylogenetic relationship.
Merits:
(i) The classification is based on the complexity of cell structure and organization of thallus.
(ii) It is based on the mode of nutrition.
(iii) Separation of fungi from plants.
(iv) It shows the phylogeny of the organisms.
Demerits:
(i) The kingdom Monera and Protista accommodate both autotrophic and heterotrophic organisms, cell wall lacking and cell wall bearing organisms thus making these two groups more heterogeneous.
(ii) Viruses are not included in the system.