Viruses were studied in earlier classes. Why are they not placed in any of the five kingdoms? Class 9

Viruses were studied in earlier classes. Why are they not placed in any of the five kingdoms? Class 9

Question 1.

Viruses were studied in earlier classes. Why are they not placed in any of the five kingdoms? Give reasons. Class 9

Answer:

Viruses are not placed in any of the five kingdoms for the following reasons: The five kingdom classification is based on characteristics of living organisms - cell type (prokaryote or eukaryote), cell structure, level of organisation (unicellular or multicellular), and mode of nutrition. Viruses do not fit any of these criteria because they are acellular - they have no cell structure at all. They do not have a cell membrane, cytoplasm, or organelles.

They are essentially genetic material (DNA or RNA) enclosed in a protein coat. Viruses are also not truly living outside a host cell - they remain inactive outside a host cell and can only replicate inside a living host cell. They do not carry out any metabolic activities on their own. Since viruses do not have a cellular organisation - the most fundamental criterion for classification - they cannot be placed in any of the five kingdoms, which are all based on cellular life forms.