Question

Six kingdom classifications was suggested by

Answer 1

An American microbiologist named the six kingdoms and suggested this classification. He was also the one who defined the Archaea by the use of phylogenetic taxonomy of S ribosomal RNA genes. Earlier there was this five-kingdom classification but it has been replaced by six kingdom classification.

Complete answer:
Carl Woese proposed the six kingdom classification with kingdoms like Archaebacteria, Eubacteria, Protista, Fungi, Plantae, and Animalia.
Carl found that the six kingdoms cluster into three main categories based on the S ribosomal RNA genes. He called these categories the domains of lives which consisted- Bacteria, Archaea, and Eukarya. He believed that these domains are descendants of the Progenote.
Archaebacteria are single-celled and thrive in extremely hot boiling water found in hot springs. They are the oldest known living organisms. Eubacteria are also single-celled that are very common and well-known parasites. Some bacteria are commercially used for the production of antibiotics and food material.
The fungi kingdom is recognizable like mushrooms, molds mildew, and yeast s. they are multicellular organisms. Protista is the protozoa family which is single-celled but more complex than eubacteria. Algae, slimes, and molds all are included in the Protista kingdom. The Plantae kingdom includes all the flowering, non-flowering plants, the mosses, lichen, and ferns. Multicellular organisms with complex body structures are autotrophic. Animalia is the largest kingdom which includes all the small and large organisms ranging from sponges to whales.

Note: Archaebacteria was separated from eubacteria due to the difference in the peptidoglycan layer in the cell wall of the archaebacteria. The kingdom Monera which was a part of the five-kingdom classification has been replaced by the kingdom Archaebacteria and kingdom Eubacteria. All organisms of the animal kingdom are Heterotrophic, unlike Autotrophic plants.