Practice question

Modern classification follows Woese's three-domain system based on 16S rRNA divergence, adding Domain as super-kingdom rank. The universally accepted descending sequence is Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species, reflecting progressively narrower shared ancestry. Domain distinguishes Bacteria, Archaea, and Eukarya; subsequent ranks show increasing phenotypic and genetic similarity. Traditional Linnaean hierarchy lacked Domain, but contemporary textbooks, NCERT Class 11, and competitive exams incorporate Domain at top to represent tree of life accurately and monophyly principles. Examinations emphasize this concept because it underpins correct interpretation of phylogenetic relationships and evolutionary systematics.