Question

How is the five–kingdom classification advantageous over the two-kingdom classification?

Answer 1

Two Kingdom systems of classification with Plantae and Animalia kingdoms.

1. Two kingdom classifications did not distinguish between the prokaryotes and eukaryotes. E.g.: It brought together the prokaryotic bacteria and blue-green algae with other groups (like plants, fungi and animals) which were eukaryotic.

2. Two kingdom classifications did not distinguish between the unicellular and multicellular organisms. E.g.: Chlamydomonas (unicellular) and Spirogyra (multicellular) were placed together under algae.

3. This system did not distinguish between autotrophic/photosynthetic (green algae and plants) and heterotrophic/non-photosynthetic organisms (fungi).

Five Kingdom Classification:

1. Fungi were placed in a separate kingdom–kingdom fungi.

2. It has put together organisms which were placed in different kingdoms in earlier classifications. Kingdom Protista brought together Chlamydomonas and Chlorella (earlier placed in algae within plants and both having cell walls) with Amoeba and Paramoecium (earlier placed in the animal kingdom and both lacking cell walls).

3. Animal and plant kingdoms become more homogenous than they are in the two kingdom classification. So, it is advantageous over the two kingdom classifications.