Five Kingdom Classification

What is one of the main criteria used by R.H. Whittaker for classifying organisms?

Which kingdom was divided into two domains in the three-domain classification system?

What significant characteristic was used to unify all organisms in the earlier classification system under 'Plants'?

Which two groups were incorrectly placed together under algae, despite their differences?

What material is found in the cell walls of fungi, differentiating them from green plants?

Five Kingdom Classification

Proposed by R.H. Whittaker in 1969.
Kingdoms identified: Monera, Protista, Fungi, Plantae, and Animalia.
Classification criteria include cell structure, body organization, mode of nutrition, reproduction, and phylogenetic relationships.

Monera and Three-Domain System

Monera is divided into two domains in the three-domain system.
Remaining eukaryotic kingdoms fall under a third domain, leading to a six-kingdom classification.

Historical Context

Earlier classification merged diverse groups like bacteria, blue-green algae, fungi, mosses, ferns, gymnosperms, and angiosperms into the ‘Plants’ kingdom.
The commonality among these organisms was the presence of a cell wall.

Classification Issues

Unification of prokaryotic bacteria and cyanobacteria (blue-green algae) with eukaryotic organisms led to generalization and oversight of significant differences.
Grouped unicellular and multicellular organisms (e.g., Chlamydomonas and Spirogyra) together under algae.
Lack of distinction between heterotrophic fungi and autotrophic green plants despite differences in cell wall composition (fungi have chitin, plants have cellulose).

Explore the Five Kingdom Classification System proposed by R.H. Whittaker in 1969. This quiz covers the various kingdoms, historical context, and issues regarding organism classification. Test your knowledge on Monera, Protista, Fungi, Plantae, and Animalia.