what are the major classification of animals and plants..? why do we classify organisms...?  

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trophyhunter1 eNotes educator| Certified Educator

Organisms are classified to show phylogenetic relationships. They are classified to show how during the course of evolution, some organisms diverged from common ancestors, while others are not closely related at all. DNA evidence and well as embryological evidence, homologous structures, cytological evidence, the fossil record are all used to construct a picture of the past. Both plants and animals are classified into the domain Eukarya. These are organisms with cells that have an organized nucleus and cell organelles. They can be placed into Kingdom Animalia and Kingdom Plantae. Animals include many phyla--some are invertebrates like Annelida, Cnidaria, Sponges, Platyhelminthes to name a few and some are classified as Chordata--including Fish, Amphibians, Reptiles, Birds and Mammals. Plantae contain moss, ferns, as well as the higher flowering plants--Angiosperms.