Understanding Biological Classification and Taxonomic Hierarchy
The classification of living organisms follows a hierarchical system that organizes life forms from broad kingdoms down to specific species. This Classification and Biodiversity WJEC framework helps scientists categorize and understand relationships between organisms.
The taxonomic hierarchy consists of Domain, Kingdom, Phylum, Class, Order, Family, Genus, and Species. Each level becomes increasingly specific, with species being the most precise classification. The three domains - Eubacteria (true bacteria), Archaea (extremophile bacteria), and Eukaryota (complex-celled organisms) - represent the broadest classification level.
Definition: The Binomial Naming System, created by Carl Linnaeus, uses genus and species names to give each organism a unique scientific identifier. This system enables clear communication between scientists globally and helps predict evolutionary relationships.
The five kingdoms - Prokaryota, Protoctista, Plantae, Fungi, and Animalia - further divide organisms based on cellular structure and complexity. Prokaryota includes simple bacteria, while Protoctista encompasses single-celled organisms with plant-like or animal-like characteristics. The Plantae kingdom contains flowering and non-flowering plants, Fungi includes both unicellular yeasts and multicellular mushrooms, and Animalia comprises complex multicellular organisms.