Textbook of Plant Chemistry

Plants are a major group of living things (about 300000 species) including familiar organisms such as trees flowers herbs and ferns. Aristotle divided all living things between plants which generally do not move or have sensory organs and animals. In Linnaeus system these became the Kingdoms Vegetabilia (later Plantae) and Animalia. Since then it has become clear that the Plantae as originally defined included several unrelated groups and the fungi and several groups of algae were removed to new kingdoms. However these are still often considered plants in many contexts. Indeed any attempt to match plant with a single taxon is doomed to fail because plant is a vaguely defined concept unrelated to the presumed phylogenic concepts on which modern taxonomy is based.