Plants are living organisms belonging to the kingdom Plantae. They include familiar organisms such as trees, herbs, bushes, grasses, vines, ferns, mosses, and green algae. The scientific study of plants, known as botany, has identified about 350,000 extant species of plants, defined as seed plants, bryophytes, ferns and fern allies. As of 2004, some 287,655 species had been identified, of which 258,650 are flowering and 18,000 bryophytes (see table below). Green plants, sometimes called Viridiplantae, obtain most of their energy from sunlight via a process called photosynthesis.
