Plants, also called green plants, are multicellular eukaryotes of the kingdom Plantae. They form a clade that includes the
Plant Diversity
flowering plants, conifers and other gymnosperms, ferns, clubmosses, hornworts, liverworts, mosses and the green algae. Plants exclude the red and brown algae, animals, the fungi, archaea and bacteria.
Green plants provide most of Earth's molecular oxygen and are the basis of most of the earth's ecosystems, especially on land. Plants that produce grains, fruits and vegetables form human's basic foods, and have been domesticated for millennia. Plants are used as ornaments and, until recently and in great variety, they have served as the source of most medicines and drugs. The scientific study of plants is known as botany, a branch of biology.